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  • 1.
    Abbas, Mhd Yazan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Ferzali, Ali
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    A mobile Application development in the Android Studio platform for leave applications2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays, there is a mobile application for almost every need, for instance, training, games, and news applications. Almost all the companies have also their own mobile applications that facilitate the daily communication between their employees and supervisors. In this thesis, the development process of an Android application for the company Askås is created, where the employees can for example send a Flex application or sick leave application, see their registered personal information and edit them. The final result of the project is almost what Askås asked for, An Android application that facilitates their employees’ daily needs. The development process, the results, and the encountered problems are also represented in a more detailed manner in the thesis. 

  • 2.
    Abdollahi, Kamran
    et al.
    Computer and Science Department Iran University of Science and Technology Tehran, Iran.
    Shams Shafigh, Alireza
    Computer and Science Department Iran University of Science and Technology Tehran, Iran.
    Kassler, Andreas
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Improving Performance of On Demand Multicast Routing by deleting lost join query packet2010In: Proceedings of The Sixth Advanced International Conference on Telecommunications - AICT 2010, IEEE conference proceedings, 2010, p. 316-322Conference paper (Refereed)
    Abstract [en]

    A Mobile ad hoc network is a collection of wireless nodes that dynamically organize themselves to form a network without the need for any fixed infrastructure or centralized administration. The network topology dynamically changes frequently in an unpredictable manner since nodes are free to move. Support for multicasting is essential in such environment as it is considered to be an efficient way to deliver information from source nodes to many client nodes. A problem with multicast routing algorithms is their efficiency as their forwarding structure determines the overall network resource consumption makes them significantly less efficient than unicast routing algorithms. In this research, we improve the performance of the popular ODMRP multicast routing protocol by restricting the domain of join query packets, which have been lost. This is achieved by augmenting the join query packets with minimum extra information (one field), which denotes the number of the visited node from previous forwarding group. Simulation results show, that our mechanisms significantly reduce the control traffic and thus the overall latency and power consumption in the network.

  • 3.
    Afzal, Zeeshan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Lindskog, Stefan
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Lidén, Anders
    A Multipath TCP Proxy2015Conference paper (Refereed)
    Abstract [en]

    Multipath TCP (MPTCP) is an extension to traditionalTCP that enables a number of performance advantages,which were not offered before. While the protocol specificationis close to being finalized, there still remain some concernsregarding deployability and security. This paper describes theon going work to develop a solution that will facilitate thedeployment of MPTCP. The solution will not only allow non-MPTCP capable end-hosts to benefit from MPTCP performancegains, but also help ease the network security concerns that manymiddleboxes face due to the possibility of data stream beingfragmented across multiple subflows.

  • 4. Agustí, Ramón
    et al.
    Fazekas, Péter
    Gómez Barquero, David
    Lindskog, Stefan
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Oliver, Miquel
    Pérez-Romero, Jordi
    Tralli, Velio
    NEWCOM DR7.2: First report on common framework/models and activities in Department 72005Report (Refereed)
    Abstract [en]

    This deliverable provides a description of the framework identified for the collaborative activities between different partners in the context of NEWCOM department 7 on QoS provision in heterogeneous wireless networks. The considered models, assumptions and expected results are pointed out for each activity. The deliverable also includes a report on the means to achieve the integration between the different partners

  • 5. Agustí, Ramón
    et al.
    Fazekas, Péter
    Lindskog, Stefan
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Oliver, Miquel
    Pérez-Romero, Jordi
    Studer Ferreira, Lucio
    Tralli, Velio
    NEWCOM DR7.4: Final Report on the activities carried out in Department 72007Report (Refereed)
    Abstract [en]

    This deliverable constitutes the final report of all the activities that carried out in the framework of the NEWCOM department 7. It contains a description of the main technical achievements for each one of the activities in which the department has been organised togehter with the list of indicators reflecting the degree of integration that has been achieved among the different partners

  • 6.
    Ahlgren, Bengt
    et al.
    RISE SICS.
    Hurtig, Per
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Abrahamsson, Henrik
    RISE SICS.
    Grinnemo, Karl-Johan
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Brunström, Anna
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    ICN Congestion Control for Wireless Links2018In: IEEE WCNC 2018 Conference Proceedings / [ed] IEEE, New York: IEEE, 2018Conference paper (Refereed)
    Abstract [en]

    Information-centric networking (ICN) with its design around named-based forwarding and in-network caching holds great promises to become a key architecture for the future Internet. Still, despite its attractiveness, there are many open questions that need to be answered before wireless ICN becomes a reality, not least about its congestion control: Many of the proposed hop-by-hop congestion control schemes assume a fixed and known link capacity, something that rarely – if ever – holds true for wireless links. As a first step, this paper demonstrates that although these congestion control schemes are able to fairly well utilise the available wireless link capacity, they greatly fail to keep the link delay down. In fact, they essentially offer the same link delay as in the case with no hop-by-hop, only end- to-end, congestion control. Secondly, the paper shows that by complementing these congestion control schemes with an easy- to-implement, packet-train link estimator, we reduce the link delay to a level significantly lower than what is obtained with only end-to-end congestion control, while still being able to keep the link utilisation at a high level. 

  • 7.
    Akrin, Christoffer
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Using Imitation Learning for Human Motion Control in a Virtual Simulation2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Test Automation is becoming a more vital part of the software development cycle, as it aims to lower the cost of testing and allow for higher test frequency. However, automating manual tests can be difficult as they tend to require complex human interaction. In this thesis, we aim to solve this by using Imitation Learning as a tool for automating manual software tests. The software under test consists of a virtual simulation, connected to a physical input device in the form of a sight. The sight can rotate on two axes, yaw and pitch, which require human motion control. Based on this, we use a Behavioral Cloning approach with a k-NN regressor trained on human demonstrations. Evaluation of model resemblance to the human is done by comparing the state path taken by the model and human. The model task performance is measured with a score based on the time taken to stabilize the sight pointing at a given object in the virtual world. The results show that a simple k-NN regression model using high-level states and actions, and with limited data, can imitate the human motion well. The model tends to be slightly faster than the human on the task while keeping realistic motion. It also shows signs of human errors, such as overshooting the object at higher angular velocities. Based on the results, we conclude that using Imitation Learning for Test Automation can be practical for specific tasks, where capturing human factors are of importance. However, further exploration is needed to identify the full potential of Imitation Learning in Test Automation.

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  • 8.
    Alfredsson, Rebecka
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Multipath transport protocol offloading2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Recently, we have seen an evolution of programmable network devices, where it is possible to customize packet processing inside the data plane at an unprecedented level. This is in contrast to traditional approaches, where networking device functionality is fixed and defined by the ASIC and customers need to wait possibly years before the vendors release new versions that add features required by customers. The vendors in the industry have adapted and the focus has shifted to offering new types of network devices, such as the SmartNIC, IPU, and DPU. Another major paradigm shift in the networking area is the shift towards protocols that encrypt parts of headers and contents of packets such as QUIC. Also, many devices such as smart phones have support for multiple access networks, which requires efficient multipath protocols to leverage the capabilities of multiple networks at the same time.

    However, when using protocols inside the network that requires encryption such as QUIC or multipath QUIC, packet processing operations for the en/decryption process are very resource intensive. Consequently, network vendors and operators are in need to accelerate and offload crypto operations to dedicated hardware in order to free CPU cycles for business critical operations. Therefore, the aim of this study is to investigate how multipath QUIC can be offloaded or hardware accelerated in order to reduce the CPU utilization on the server.

    Our contributions are an evaluation of frameworks, programming languages and hardware devices in terms of crypto offloading functionality. Two packet processing offloading prototypes were designed using the DPDK framework and the programming language P4. The design using DPDK was implemented and evaluated on a BlueField 2 DPU. The offloading prototype handles a major part of the packet processing and the crypto operations in order to reduce the load of the user application running on the host. A evaluation show that the throughput when using larger keys are only slightly decreased. The evaluation gives important insights in the need of crypto engines and/or CPUs with high performance when offloading.

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  • 9.
    Alfredsson, Stefan
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    A Cross-Layer Perspective on Transport Protocol Performance in Wireless Networks2012Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Communication by wireless technologies has seen a tremendous growth in the last decades. Mobile phone technology and wireless broadband solutions are rapidly replacing the last-hop wireline connectivity for telephones and Internet access.  Research has, however, shown that Internet traffic can experience a performance degradation over wireless compared to wired networks.  The inherent properties of radio communication lead to a higher degree of unreliability, compared to communication by wire or fiber.  This can result in an increased amount of transmission errors, packet loss, delay and delay variations, which in turn affect the performance of the main Internet transport protocols TCP and UDP.  This dissertation examines the cross-layer relationship between wireless transmission and the resulting performance on the transport layer. To this end, experimental evaluations of TCP and UDP over a wireless 4G downlink system proposal are performed.  The experiment results show, in a holistic scenario, that link-level adaptive modulation, channel prediction, fast persistent link retransmissions, and channel scheduling, enables the transport protocols TCP and UDP to perform well and utilize the wireless link efficiently.  Further, a novel approach is proposed where a modified TCP receiver can choose to accept packets that are corrupted by bit errors. Results from network emulation experiments indicate that by accepting and acknowledging even small amounts of corrupted data, a much higher throughput can be maintained compared to standard TCP.

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  • 10.
    Alfredsson, Stefan
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Division for Information Technology.
    Brunstrom, Anna
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Division for Information Technology.
    Mikael, Sternad
    Signaler och System, Uppsala universitet.
    A 4G Link Level Emulator for Transport Protocol Evaluation2004In: Proceedings of The Second Swedish National Computer Networking Workshop (SNCNW), 2004, p. 19-23Conference paper (Refereed)
    Abstract [en]

    This paper presents a wireless link and networkemulator, based upon the "Wireless IP" 4G system proposalfrom Uppsala University and partners. In wireless fading down-links (base to terminals) link-level frames are scheduled andthe transmission is adapted on a fast time scale. With fastlink adaptation and fast link level retransmission, the fading properties of wireless links can to a large extent be counteractedat the physical and link layers. A purpose of the emulatoris to investigate the resulting interaction with transport layer protocols. The emulator is built on Internet technologies, andis installed as a gateway between communicating hosts. The paper gives an overview of the emulator design, and presentspreliminary experiments with three different TCP variants. The results illustrate the functionality of the emulator by showing theeffect of changing link layer parameters on the different TCP variants.

  • 11.
    Alfredsson, Stefan
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Brunstrom, Anna
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Mikael, Sternad
    Signaler och System, Uppsala universitet.
    Cross-layer analysis of TCP performance in a 4G system2007In: Proceedings of the 15th International Conference on Software, Telecommunications and Computer Networks, IEEE Computer Society, 2007Conference paper (Refereed)
    Abstract [en]

    This paper presents results from an experimental study of TCP in a wireless 4G evaluation system. Test-bed results on transport layer performance are presented and analyzed in relation to several link layer aspects. The aspects investigated are the impact of channel prediction errors, channel scheduling, delay, and adaptive modulation switch level, on TCP performance. The paper contributes a cross-layer analysis of the interaction between symbol modulation levels, different scheduling strategies, channel prediction errors and the resulting frame retransmissions effect on TCP. The paper also shows that highly persistent ARQ with fast link retransmissions do not interact negatively with the TCP retransmission timer even for short round trip delays.

  • 12.
    Alfredsson, Stefan
    et al.
    Karlstad University, Division for Information Technology. Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Brunstrom, Anna
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Division for Information Technology.
    Mikael, Sternad
    Signaler och System, Uppsala universitet.
    Emulation and Validation of a 4G System Proposal2005In: Proceedings of RadioVetenskap och Kommunikation 2005: Volume II, 2005, p. 357-362Conference paper (Refereed)
    Abstract [en]

    This paper presents a wireless link and network emulator,along with experiments and validation against the "Wireless IP" 4G system proposal from Uppsala University and partners. In wireless fading downlinks (base to terminals) link-level frames are scheduled and the transmission is adapted on a fast time scale. With fast link adaptation and fast link level retransmission, the fading properties of wireless links can to a large extent be counteracted at thephysical and link layers. The emulator has been used to experimentally investigate the resulting interaction between the transport layer and the link layer. The paper gives an overview of the emulator design, and presents experimental results with three different TCP variants in combination with various link layer characteristics.

  • 13.
    Alfredsson, Stefan
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Brunstrom, Anna
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Mikael, Sternad
    Signaler och System, Uppsala universitet.
    Impact of 4G Wireless Link Configurations on VoIP Network Performance2008In: Proceedings of the 2008 IEEE International Symposium on Wireless Communication Systems, IEEE Communications Society, 2008, p. 708-712Conference paper (Refereed)
    Abstract [en]

    The performance of applications in wireless networks is partly dependent upon the link configuration. Link characteristics varies with frame retransmission persistency, link frame retransmission delay, adaptive modulation strategies, coding, and more. The link configuration and channel conditions can lead to packet loss, delay and delay variations, which impact different applications in different ways. A bulk transfer application may tolerate delays to a large extent, while packet loss is undesirable. On the other hand, real-time interactive applications are sensitive to delay and delay variations, but may tolerate packet loss to a certain extent. This paper contributes a study of the effect of link frame retransmission persistency and delay on packet loss and latency for real-time interactive applications. The results indicate that a reliable retransmission mechanism with fast link retransmissions in the range of 2-8 ms is sufficient to provide an upper delay bound of 50 ms over the wireless link, which is well within the delay budget of voice over IP applications.

  • 14.
    Alfredsson, Stefan
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Brunstrom, Anna
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Mikael, Sternad
    Signaler och System, Uppsala universitet.
    Transport Protocol Performance over 4G Links: Emulation Methodology and Results2006In: Proceedings of the International Symposium on Wireless Communication Systems (ISWCS), IEEE Computer Society, 2006, p. 327-332Conference paper (Refereed)
    Abstract [en]

    This paper presents a wireless link and network emulator for the "Wireless IP" 4G system proposal from Uppsala University and partners. In wireless fading downlinks (base to terminals) link-level frames are scheduled and the transmission is adapted on a fast time scale. With fast link adaptation and fast link level retransmission, the fading properties of wireless links can to a large extent be counteracted at the physical and link layers. The emulator has been used to experimentally investigate the resulting interaction between the transport layer and the physical/link layer in such a downlink. The paper introduces the Wireless IP system, describes the emulator design and implementation, and presents experimental results with TCP in combination with various physical/link layer parameters. The impact of link layer ARQ persistency, adaptive modulation, prediction errors and simple scheduling are all considered.

  • 15. Ali Yahiya, Tara
    et al.
    Chaouchi, Hakima
    Kassler, Andreas
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Pujolle, Guy
    Seamless Interworking of WLAN and WMAN Wireless Networks2006Conference paper (Refereed)
    Abstract [en]

    Future network environments will be heterogeneous and mobile terminals will have the opportunity to dynamically select among many different access technologies. Therefore, it is important to provide service continuity in case of vertical handovers when terminals change the access technology. Two important wireless access technologies are WLAN (Wireless Local Access Networks) and WMAN (Wireless Metropolitan Access Networks) networks. In this paper, we address several challenges related to a seamless integration of those technologies. We highlight important aspects for designing a WLAN/WMAN interworking architecture and we address important Quality of Service (QoS) issues for such interworked systems like degree of QoS support provided by the technologies, QoS mapping and signalling for vertical handover. By formulating several interworking scenarios, where WLAN users with ongoing voice, video and data sessions hand over to WMAN, we study QoS and performance issues and analyse feasibility of seamless session continuity through simulations

  • 16.
    Alizadeh Noghani, Kyoomars
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kassler, Andreas
    Karlstad University, Faculty of Economic Sciences, Communication and IT (discontinued), Department of Computer Science.
    Taheri, Javid
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Ohlen, Peter
    Ericsson Research, Sweden.
    Curescu, Calin
    Ericsson Research, Sweden.
    Multi-Objective genetic algorithm for fast service function chain reconfiguration2023In: IEEE Transactions on Network and Service Management, ISSN 1932-4537, E-ISSN 1932-4537, Vol. 20, no 3, p. 3501-3522Article in journal (Refereed)
    Abstract [en]

    The optimal placement of virtual network functions (VNFs) improves the overall performance of servicefunction chains (SFCs) and decreases the operational costs formobile network operators. To cope with changes in demands,VNF instances may be added or removed dynamically, resourceallocations may be adjusted, and servers may be consolidated.To maintain an optimal placement of SFCs when conditionschange, SFC reconfiguration is required, including the migration of VNFs and the rerouting of service-flows. However, suchreconfigurations may lead to stress on the VNF infrastructure,which may cause service degradation. On the other hand, notchanging the placement may lead to suboptimal operation,and servers and links may become congested or underutilized,leading to high operational costs. In this paper, we investigatethe trade-off between the reconfiguration of SFCs and theoptimality of their new placement and service-flow routing. Wedevelop a multi-objective genetic algorithm that explores thePareto front by balancing the optimality of the new placementand the cost to achieve it. Our numerical evaluations show thata small number of reconfigurations can significantly reduce theoperational cost of the VNF infrastructure. In contrast, toomuch reconfiguration may not pay off due to high costs. Webelieve that our work provides an important tool that helpsnetwork providers to plan a good reconfiguration strategy fortheir service chains.

  • 17. Allman, Mark
    et al.
    Avrachenkov, Konstatin
    Ayesta, Urtzi
    Blanton, Josh
    Hurtig, Per
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Early Retransmit for TCP and SCTP2008Other (Other (popular science, discussion, etc.))
    Abstract [en]

    This document proposes a new mechanism for TCP and SCTP that can be used to recover lost segments when a connection's congestion window is small. The "Early Retransmit" mechanism allows the transport to reduce, in certain special circumstances, the number of duplicate acknowledgments required to trigger a fast retransmission. This allows the transport to use fast retransmit to recover packet losses that would otherwise require a lengthy retransmission timeout.

  • 18.
    Altonchi, Alan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Hising Bertils, Emil
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Adding new features to a physical exercise web application2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 19.
    Alvin, Axel
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Axelborn, Lukas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Masterdata och API2022Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today’s society depends on a constant flow of information and data. Companies and organisations often hold huge amounts of data, ranging from customers and staff to sales statistics and patient records. The pace of change has been very fast and many companies and organisations have not had the time or resources to keep their systems up to date to handle these huge amounts of data. In this thesis, the task has been to link databases from multiple systems to make maintenance and management easier. These systems generally process the same type of data (personnel data divided into groups in the form of units) which are named in different ways, for example with different IDs. As a result, the data is unrelated in a way that makes it very difficult to determine which entities correspond to each other as they have no common denominator. As a solution to this, two additional databases were created and linked to each other through an API, where the data is linked by being assigned a common ID, or a master-ID. In this way, users and developers can easily search for an object from one system and get in return all the data for the corresponding objects in other systems. In addition, a semi-automated system was created in the form of a user interface used for linking objects.

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  • 20. Andersson, Carin
    et al.
    Lindskog, Stefan
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Survey and Analysis of Project Management Competence within Research Projects at Karlstad University2007Other (Other (popular science, discussion, etc.))
    Abstract [en]

    Research at universities is today often conducted as projects. This is especially true in the engineering, natural science, medicine, and social science disciplines. Research projects are typically carried out by different categories of employers, such as professors, associate professors, assistant professors, and PhD students. These projects are typically managed by the person that applied for the project money, or the person that is the most experienced researcher at the department, which is often a professor or associate professor. From such leading persons, miracles are expected. Except acting as project managers, they are also engaged in many other parallel activities, e.g., supervision of PhD students, undergraduate and graduate education, conference organization and administration, project application writing, and representing the department internally as well as externally.



    In this report, a survey of project management competence within research projects at Karlstad University is presented. Empirical data have been gathered through two questionnaires and six complementary interviews. Professors and associate professors as well as PhD students have participated in the study. The survey shows that the active project managers have learned to lead projects based on experience and very few project managers have a formal leadership education. This implies that long established project management methods and tools are seldom used.



    Based on the outcome from the survey and our own observations, four concrete activities to improve project management skills are proposed in the report. The first activity is to provide a suitable and well-balanced course in project management methods that is offered to both active and future project managers. The second activity is to establish experience networks among active project mangers at Karlstad University. The third activity is to create a mentor program for new project managers. The fourth activity is to establish a group of experienced project managers that can assist in and give support to ongoing and planned projects.

  • 21. Andersson, Christer
    et al.
    Fischer Hübner, Simone
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Lundin, Reine
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Enabling anonymity for the mobile Internet using the mCrowds system2004In: Risk and Challenges of the Network Society: Proceedings of the Second IFIP WG 9.2, 9.6/11.6, 11.7 International Summer School / [ed] Penny Duquenoy, Simone Fischer-Hübner, Jan Holvast, and Albin Zuccato, Karlstad University Press, 2004, p. 178-189Chapter in book (Refereed)
    Abstract [en]

    The mobile Internet is a fast growing technology that introduces new privacy risks. We argue that, since privacy legislation alone is not sufficient to protect the users privacy, technical solutions to enhanceinformational privacy of individuals are also needed. This paper introduces mCrowds, a privacy-enhancing technology that combines the concept of a crowd system in a mobile Internet setting with a filteringfunctionality to enable anonymity towards the content providers

  • 22.
    Andersson, Christer
    et al.
    Karlstad University, Division for Information Technology.
    Fischer-Hübner, Simone
    Karlstad University, Division for Information Technology. Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Lundin, Reine
    Karlstad University, Division for Information Technology. Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    mCrowds: Anonymity for the Mobile Internet2003In: HumanIT 2003, Karlstad: Karlstad University Press, 2003, p. 79-92Chapter in book (Refereed)
  • 23. Andersson, Christer
    et al.
    Lundin, Reine
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    On the Fundamentals of Anonymity Metrics2007In: The Future of Identity in the Information Society: Proceedings of the Third IFIP WG 9.2, 9.6/ 11.6, 11.7/FIDIS International Summer School on The Future of Identity in the Information Society / [ed] Simone Fischer-Hübner, Penny Duquenoy, Albin Zuccato and Leonardo Martucci, 2007Conference paper (Refereed)
  • 24.
    Andersson, Christer
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Martucci, Leonardo A.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Privacy & Anonymity in Mobile Ad Hoc Networks2008In: Handbook of Research on Wireless Security / [ed] Yan Zhang, Jun Zheng & Miao Ma, IGI Global , 2008Chapter in book (Other academic)
  • 25. Andersson, Christer
    et al.
    Martucci, Leonardo
    Fischer Hübner, Simone
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Privacy and Anonymity in Mobile Ad Hoc Networks2008In: Mobile Computing: Concepts, Methodologies, Tools, and Applications / [ed] David Taniar, Information Science Reference , 2008Chapter in book (Refereed)
  • 26. Andersson, Christer
    et al.
    Martucci, Leonardo
    Fischer Hübner, Simone
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Privacy Requirements for Mobile Ad Hoc Networks2005Conference paper (Refereed)
  • 27.
    Andersson, David
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Teoretisk och praktisk genomgång av IPv6 och dess säkerhetsaspekter2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper takes a theoretical as well as a practical approach to what IPv6 is in order to create an understanding for the new protocol. In addition to the theoretical review of the protocol, this paper also describes the work that has been done in order to create an implementation that is supposed to bring  secure IPv6 support to both private individuals and smaller organizations, even if the Internet service provider only offers IPv4.

     

    This paper and implementation is done on a personal initiative, since the need for knowledge regarding IPv6 is rapidly increasing and private individuals probably will be among the last to be offered native IPv6 support from their Internet service providers.

    Download full text (pdf)
    Teoretisk och praktisk genomgång av IPv6 och dess säkerhetsaspekter
  • 28.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    CASSCF second-order perturbation theory (CASPT2)1998In: Encyclopedia of Computational Chemistry / [ed] P. von Ragué Schleyer, Chichester, England: John Wiley & Sons , 1998Chapter in book (Refereed)
  • 29.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Cellular Automata2003Other (Other (popular science, discussion, etc.))
    Abstract [en]

    Properties and behavior of cellular automata are considered. Cellular automata can simply be described as lattices of cells, where the cells can be in a finite number of states. By using simple rules the states of the cells are updated at discrete time steps. The evolution of cellular automata can be used for computations. Some cellular automata display universality meaning that there is no limit to the sophistication of the computations they can perform.

  • 30.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Cellular Automata2004In: Promote IT 2004: proceedings of the fourth Conference for the Promotion of Research in IT at New Universities and University Colleges in Sweden : 5-7 May, 2004, Karlstad University, Sweden. P. 1 / [ed] Bubenko, Janis, Karlstad: Karlstad University Press , 2004, Vol. 2004:26, p. 598-608Conference paper (Refereed)
    Abstract [en]

    In this paper properties and behavior of cellular automata are considered. Cellular automata can simply be described as lattices of cells, where the cells can be in a finite number of states. By using simple rules the states of the cells are updated in parallel at discrete time steps. Depending on the rule and, to a certain degree, the initial states of the cells, the evolution of a cellular automaton is restricted to a small number a ways. Some cellular automata evolve uniformly, meaning that all cells end up in the same state, while others evolve randomly, meaning that the states of the cells appear to be totally randomized during evolution. Intermediate behavior, displaying repetitiveness or nesting, also occurs.Properties of cellular automata that are discussed in the paper are, for instance, sensitivity to initial conditions, randomness, reversibility, entropy, and conservation. These properties also appear in the physical world and cellular automata provide good examples in the understanding of these properties.The evolution of cellular automata can be used for computations. Some cellular automata even display the property of universality, a term well known from the universal Turing machine, meaning that there is no limit to the sophistication of the computations they can perform.

  • 31.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Cellular Automata2005In: Promote IT 2005: proceedings of the fifth Conference for the Promotion of Research in IT at New Universities and University Colleges in Sweden : Borlänge, Sweden 11-13 May, 2005 / [ed] Bubenko, Janis, Lund: Studentlitteratur , 2005, p. 21-30Conference paper (Refereed)
    Abstract [en]

    Cellular automata have a widespread use in the description of complex phenomena in disciplines as disparate as for example physics and economics. They are described by a lattice of cells, states of the cells, and rules for updating the states of the cells. One characteristics of a cellular automaton is the simplicity of the rules that determine how the cellular automaton evolves in time. These rules are local, are applied in parallel to all the cells and despite their simplicity they may give rise to a complex macroscopic behaviour. In this paper this is illustrated by examples from hydrodynamics and it is shown that cellular automata might provide powerful alternatives to partial differential equations

  • 32.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Cellular Automata in Science2005Other (Other (popular science, discussion, etc.))
    Abstract [en]

    Cellular automata have a widespread use in the description of complex phenomena in disciplines as disparate as, for example, physics and economics. A cellular automaton is a lattice of cells, and the cells can be in a finite number of states. By using simple local rules the states of the cells are updated in parallel at discrete time steps. In short, a cellular automaton can be characterised by the three words - simple, local, and parallel. These three words are one of the reasons for the attractiveness of cellular automata. They are simple to implement and they are well suited for parallel computers (computations). Another reason for using cellular automata are for their spatio-temporal properties. The lattice may represent space and the updating of the cells gives a

    dimension of time.



    In spite of the simplicity of cellular automata they may give rise to a complex macroscopic behaviour. This is illustrated, in this thesis, by an hydrodynamic example, namely the creation of vortices in flow behind a cylinder.



    Although cellular automata have the ability to describe complex phenomena it is sometimes hard to find the proper rules for a given macroscopic behaviour. One approach which has been successfully employed is to let cellular automata rules evolve (for example, through genetic algorithms) when finding the desired properties. In this thesis this is demonstrated for two-dimensional cellular automata with two possible states of the cells. A genetic algorithm is used to find rules that evolve a given initial configuration of the cells to another given configuration.

  • 33.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Different forms of the zeroth-order Hamiltonian in second-order perturbation theory with a complete active space self-consistent field reference function1995In: Theoretica Chimica Acta, 91:31Article in journal (Refereed)
  • 34.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Multiconfigurational perturbation theory1992Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The aim of the thesis is to analyze a method which describes the electron correlation in atoms and molecules. The method is based on Rayleigh-Schrödinger perturbation theory with a partitioning of the Hamiltonian into a fairly simple zeroth-order operator and a perturbation operator. The zeroth-order Hamiltonian is founded on a one-electron Fock-type operator and two different operators have been tested. The zeroth-order wave function is constructed from a complete active space self-consistent field (CASSCF) calculation. This means that the zeroth-order wave function for open-shell systems and systems with strong configurational mixing (near degeneracy) can be obtained on an equal level as closed-shell (single determinant) states. The theory is formulated in such a way that the Möller-Plesset perturbation theory is obtained for the closed-shell (single determinant) state. The flexibility of the CASSCF method makes it possible, in principle, to construct the zeroth-order wave function (and the zeroth-order Hamiltonian) to any desired accuracy. The perturbation expansion of the energy is therefore expected to converge fast and only up to the second-order contribution has been implemented leading to fairly fast and accurate calculations. The aim of the computer implementation is to describe the electron correlation in small and medium-sized molecules (up to 20 atoms) accurately. The application of the perturbation method to a number of problems in chemistry is demonstrated in the thesis: (1) the calculation of electronic properties and harmonic vibrational frequencies of the ozone molecule; (2) the calculation of electric dipole polarizabilities of excited valence states of several first- and second-row atoms; (3) the calculation of excited states of the nickel atom, the benzene molecule, and the azabenzenes pyridine, pyrazine, pyridazine, and s-triazine

  • 35.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Numerical Evaluation of the Average Number of Successive Guesses2012In: Unconventional Computation and Natural Computation: 11th International Conference, UCNC 2012, Orléans, France, September 3-7, 2012, Proceedings / [ed] Jérôme Durand-Lose, Natasa Jonoska, Berlin Heidelberg: Springer , 2012, p. 234-234Conference paper (Refereed)
  • 36.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    The electronic spectrum of Cr21995In: Chemical Physics Letters, 237:212Article in journal (Refereed)
  • 37.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    The electronic spectrum of VCr2003In: Theoretical Chemistry Accounts, volume 110, number 3Article in journal (Refereed)
    Abstract [en]

    The electronic spectrum of VCr has been studied using the complete-active-space self-consistent field complete-active-space second-order perturbation theory approach. Potential energy curves for 12 electronic states have been computed. Transition energies, with respect to the X^2Delta ground state, for some of the calculated electronic states are (with possible experimental values within parentheses): 0.53 eV (0.56) for A^2Sigma+, 1.03 eV (1.14) for A^4Delta, 1.20 eV (1.14) for B^2Delta, 1.45 eV (1.51) for B^4Delta, 1.60 eV (1.51, 1.78) for C^2Delta, and 1.61 eV (1.63) for A^4Sigma^-.

  • 38.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Vad är det för kunskap som värderas?2000In: Universitetsläraren, nummer 7Article in journal (Other (popular science, discussion, etc.))
  • 39.
    Andersson, Kerstin
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Vad är kunskap?2006In: Kapet, nummer 1, Vol. 1Article in journal (Other (popular science, discussion, etc.))
  • 40.
    Andersson, Kerstin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Bauschlicher Jr., C. W.
    Persson, B. J.
    Roos, B. O.
    The structure of dichromium tetraformate1996In: Chemical Physics Letters, 257:238Article in journal (Refereed)
  • 41.
    Andersson, Kerstin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Borowski, P.
    Fowler, P. W.
    Malmqvist, P.-Å.
    Roos, B. O.
    Sadlej, A. J.
    Electric properties of the ozone molecule1992In: Chemical Physics Letters, 190:367Article in journal (Refereed)
  • 42.
    Andersson, Kerstin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Fulscher, M. P.
    Lindh, R.
    Malmqvist, P.-Å.
    Olsen, J.
    Roos, B. O.
    Widmark, P.-O.
    MOLCAS: A general purpose quantum chemistry program system for correlated wavefunctions1994In: Methods and Techniques in Computational Chemistry: METECC-94, chapter 7, page 275 / [ed] Enrico Clementi, Cagliari, Italy: STEF , 1994Chapter in book (Refereed)
  • 43.
    Andersson, Kerstin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Malmqvist, P.-Å.
    Roos, B. O.
    Second-order perturbation theory with a complete active space self-consistent field reference function1992In: Journal of Chemical Physics, 96:1218Article in journal (Refereed)
  • 44.
    Andersson, Kerstin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Malmqvist, P.-Å.
    Roos, B. O.
    Sadlej, A. J.
    Wolinski, K.
    Second-order perturbation theory with a CASSCF reference function1990In: Journal of Physical Chemistry, 94:5483Article in journal (Refereed)
  • 45.
    Andersson, Kerstin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Roos, B. O.
    Excitation energies in the nickel atom studied with the complete active space SCF method and second-order perturbation theory1992In: Chemical Physics Letters, 191:507Article in journal (Refereed)
  • 46.
    Andersson, Kerstin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Roos, B. O.
    Multiconfigurational second-order perturbation theory1995In: Modern electronic structure theory, volume 1 / [ed] D. R. Yarkony, New York: World Scientific Publishing , 1995Chapter in book (Refereed)
  • 47.
    Andersson, Kerstin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Roos, B. O.
    Multiconfigurational second-order perturbation theory: A test of geometries and binding energies1993In: International Journal of Quantum Chemistry, 45:591Article in journal (Refereed)
  • 48.
    Andersson, Kerstin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Roos, B. O.
    Malmqvist, P.-Å.
    Widmark, P.-O.
    The Cr2 potential energy curve studied with multiconfigurational second-order perturbation theory1994In: Chemical Physics Letters, 230:391Article in journal (Refereed)
  • 49.
    Andersson, Kerstin
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Sadlej, A. J.
    Electric dipole polarizabilities of atomic valence states1992In: Physical Review A, 46:2356Article in journal (Refereed)
  • 50.
    Angulo, Julio
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Information Systems and Project Management.
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Pulls, Tobias
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Ulrich, König
    HCI for Policy Display and Administration2011In: Privacy and Identity Management for Life / [ed] Jan Camenish, Simone Fischer-Hübner and Kai Rannenberg, Berlin: Springer Berlin/Heidelberg, 2011, 1, p. 261-277Chapter in book (Refereed)
    Abstract [en]

    The PrimeLife Policy Language (PPL) has the objective of helping end users make the data handling practices of data controllers more transparent, allowing them to make well-informed decisions about the release of personal data in exchange for services. In this chapter, we present our work on user interfaces for the PPL policy engine, which aims at displaying the core elements of a data controller's privacy policy in an easily understandable way as well as displaying how far it corresponds with the user's privacy preferences. We also show how privacy preference management can be simplified for end users.

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