miun.sePublikasjoner
Endre søk
Begrens søket
12 1 - 50 of 87
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Barac, Filip
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Caiola, Stefano
    Natl Instruments Italy, I-20090 Milan, Italy.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Sisinni, Emiliano
    Univ Brescia, Dept Informat Engn, I-25123 Brescia, Italy.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Channel Diagnostics for Wireless Sensor Networks in Harsh Industrial Environments2014Inngår i: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 14, nr 11, s. 3983-3995Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wireless sensor network communication in industrial environments is compromised by interference, multipath fading, and signal attenuation. In that respect, accurate channel diagnostics is imperative to selecting the adequate countermeasures. This paper presents the lightweight packet error discriminator (LPED) that infers the wireless link condition by distinguishing between errors caused by multipath fading and attenuation, and those inflicted by interfering wideband single-channel communication systems (e.g., IEEE 802.11b/g), based on the differences in their error footprints. The LPED uses forward error correction in a novel context, namely, to determine the symbol error density, which is then fed to a discriminator for error source classification. The classification criteria are derived from an extensive set of error traces collected in three different types of industrial environments, and verified on a newly collected set of error traces. The proposed solution is evaluated both offline and online, in terms of classification accuracy, speed of channel diagnostics, and execution time. The results show that in ≥91% of cases, a single packet is sufficient for a correct channel diagnosis, accelerating link state inference by at least 270%, compared with the relevant state-of-the-art approaches. The execution time of LPED, for the worst case of packet corruption and maximum packet size, is below 30 ms with ≤3% of device memory consumption. Finally, live tests in an industrial environment show that LPED quickly recovers from link outage, by losing up to two packets on average, which is only one packet above the theoretical minimum.

  • 2.
    Barac, Filip
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Channel Coding and Interleaving in Industrial WSN: Abiding to Timing Constraints and Bit Error Nature2013Inngår i: Proceedings - M and N 2013: 2013 IEEE International Workshop on Measurements and Networking, 2013, s. 46-51Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Forward Error Correction is a preemptive manner of improving communication reliability. Albeit not a part of IEEE 802.15.4-2006 standard, its application in Industrial Wireless Sensor Networks has been widely considered. Nevertheless, this study is the first performance analysis on real error traces with sufficiently lightweight channel codes, with respect to IEEE 802.15.4-2006 and industrial wireless communication timing constraints. Based on these constraints and bit error properties from the collected traces, the use of Reed-Solomon (15,7) block code is suggested, which can be implemented in software. Experiments show that bit error nature on links affected by multipath fading and attenuation in industrial environments is such that RS(15,7) can correct ≥95% of erroneously received packets, without the necessity for interleaving. On links under IEEE 802.11 interference, typically up to 50% of corrupted packets can be recovered by combining RS(15,7) with symbol interleaving, which has proven to be more effective than its bit counterpart. The optimal interleaving depth is found empirically and it is shown that simple bit-interleaved 1/3 repetition code achieves at least 90% of correcting performance of RS(15,7) code on uninterfered links that operate ≥10 dB above the sensitivity threshold.

  • 3.
    Barac, Filip
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    CLAP: Chip-Level Augmentation of IEEE 802.15.4 PHY for Error-Intolerant WSN Communication2015Inngår i: IEEE Vehicular Technology Conference, Glasgow, Scotland: IEEE Vehicular Technology Society , 2015, s. 1-7Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Communication reliability is the ultimate priority in safety-critical wireless sensor network (WSN) communication. Surprisingly enough, the enormous potential of error control on direct sequence spread spectrum (DSSS) chips in IEEE 802.15.4 has been completely overlooked by the WSN community, possibly due to incorrect presumptions, such as the concerns about computational overhead. Current error-correction schemes in WSN counteract the error process once the errors have already propagated to bit- and packet-level. Motivated by the notion that errors should be confronted at the earliest stage, this work presents CLAP, a novel method that tremendously improves the error correction in WSN by fortifying the IEEE 802.15.4 Physical layer (PHY) with straightforward manipulations of DSSS chips. CLAP is implemented on a software-defined radio platform, and evaluated on real error traces from heavily WLAN-interfered IEEE 802.15.4 transmissions at 3 different environments. CLAP boosts the number of corrected packets by 1.78-6.88 times on severely interfered links, compared to two other state-of-the-art schemes. The overhead in terms of computational complexity is about 10% of execution time of the OQPSK demodulator in the legacy IEEE 802.15.4 receiver chain.

  • 4.
    Barac, Filip
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    LPED: Channel Diagnostics in WSN Through Channel Coding and Symbol Error Statistics2014Inngår i: IEEE ISSNIP 2014 - 2014 IEEE 9th International Conference on Intelligent Sensors, Sensor Networks and Information Processing, Conference Proceedings, Singapore: IEEE Sensors Council, 2014, s. 1-6Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Three major obstacles to wireless communication are electromagnetic interference, multipath fading and signal attenuation. The former stems mainly from collocated wireless systems operating in the same frequency band, while the latter two originate from physical properties of the environment. Identifying the source of packet corruption and loss is crucial, since the adequate countermeasures for different types of threats are essentially different. This problem is especially pronounced in industrial monitoring and control applications, where IEEE 802.15.4 communication is expected to deliver data within tight deadlines, with minimal packet loss. This work presents the Lightweight Packet Error Discriminator (LPED) that distinguishes between errors caused by multipath fading and attenuation, and those inflicted by IEEE 802.11 interference. LPED uses Forward Error Correction to determine the symbol error positions inside erroneously received packets and calculates the error density, which is then fed to a discriminator for error source classification. The statistical constituents of LPED are obtained from an extensive measurement campaign in two different types of industrial environments. The classifier incurs no overhead and in ≥90% of cases a single packet is sufficient for a correct channel diagnosis. Experiments show that LPED accelerates link diagnostics by at least 190%, compared to the relevant state-of-the-art approaches.

  • 5.
    Barac, Filip
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    PREED: Packet Recovery by Exploiting the Determinism in Industrial WSN Communication2015Inngår i: Proceedings - IEEE International Conference on Distributed Computing in Sensor Systems, DCOSS 2015, Fortaleza, Brazil: IEEE Computer Society, 2015, s. 81-90Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The requirements of safety-critical wireless sensornetwork (WSN) applications, such as closed-loop control andtraffic safety, cannot be met by the IEEE 802.15.4-2006 standardnor its industrial WSN (IWSN) derivatives. The main problem inthat respect is the communication reliability, which is seriouslycompromised by 2.4-GHz interference, as well as multipathfading and attenuation (MFA) at industrial facilities. Meanwhile,communication blackouts in critical WSN applications maylead to devastating consequences, including production halts,damage to production assets and can pose a threat to safetyof human personnel. This work presents PREED, a method toimprove the reliability by exploiting the determinism in IWSNcommunication. The proposed solution is based on the analysisof bit error traces collected in real transmissions at four differentindustrial environments. A case study on WirelessHART packetformat shows that PREED recovers 42%-134% more packetsthan the competing approaches on links compromised by WLANinterference. In addition, PREED reduces one of the most trivialcauses of packet loss in IWSN, i.e. the corruption offrame lengthbyte, by 88% and 99%, for links exposed to WLAN interferenceand MFA, respectively.

  • 6.
    Barac, Filip
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. ABB Corp Res, S-72178 Vasteras, Sweden.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Scrutinizing Bit- and Symbol-Errors of IEEE 802.15.4 Communication in Industrial Environments2014Inngår i: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 63, nr 7, s. 1783-1794Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The knowledge of error nature in wireless channels is an essential constituent of efficient communication protocol design. To this end, this paper is the first comprehensive bit- and symbol-level analysis of IEEE 802.15.4 transmission errors in industrial environments. The intention with this paper is to extract the error properties relevant for future improvements of wireless communication reliability and coexistence of radio systems in these harsh conditions. An extensive set of bit-error traces was collected in a variety of scenarios and industrial environments, showing that error behavior is highly dependent on the cause of packet corruption. It is shown that errors inflicted by multipath fading and attenuation exhibit different properties than those imposed by IEEE 802.11 interference. The statistical behavior of these two patterns is concurrently investigated in terms of differences in bit-error distribution, error burst length, channel memory length, and the scale of packet corruption. With these conclusions at hand, abiding to the computational constraints of embedded sensors and the statistical properties of bit-errors, a Reed-Solomon $(15,k)$ block code is chosen to investigate the implications of bit-error nature on practical aspects of channel coding and interleaving. This paper is concluded by a number of findings of high practical relevance, concerning the optimal type, depth, and meaningfulness of interleaving.

  • 7.
    Barac, Filip
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Ubiquitous, yet Deceptive: Hardware-Based Channel Metrics on Interfered WSN Links2015Inngår i: IEEE Transactions on Vehicular Technology, ISSN 0018-9545, E-ISSN 1939-9359, Vol. 64, nr 5, s. 1766-1778Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The ease of acquiring hardware-based link quality indicators is an alluring property for fast channel estimation in time- and safety-critical Wireless Sensor Network (WSN) applications, such as closed-loop control and interlocking. The two rudimentary hardware-based channel quality metrics, Received Signal Strength (RSS) and Link Quality Indicator (LQI), are the key constituents of channel estimation and a plethora of other WSN functionalities, from routing to transmit power control. Nevertheless, this study highlights three deficient aspects of these two indicators: 1) overall deceptiveness, i.e. the inability to reveal the presence of interference, falsely indicating excellent channel conditions in an unacceptably high fraction of cases; 2) the burstiness of missed detections, which compromises the attempts to eliminate the deceptiveness by averaging; 3) high mutual discrepancy of the two indicators, observed in 39-73% of packets, throughout different scenarios. The ability of RSS and LQI to indicate IEEE 802.11 interference is scrutinized in a variety of scenarios in typical industrial environments, using commercialoff- the-shelf hardware and realistic network topologies, giving the findings of this study a high general validity and practical relevance.

  • 8.
    Barac, Filip
    et al.
    Ericsson AB.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Sisinni, Emiliano
    University of Brescia.
    Error Manifestation in Industrial WSN Communication and Guidelines for Countermeasures2017Inngår i: Wireless Sensor Systems for Extreme Environments: Space, Underwater, Underground and Industrial / [ed] H. F. Rashvand and A. Abedi, John Wiley & Sons, 2017Kapittel i bok, del av antologi (Fagfellevurdert)
  • 9.
    Dobslaw, Felix
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tinting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Challenges for the use of data aggregation in industrial Wireless Sensor Networks2015Inngår i: IEEE International Conference on Automation Science and Engineering, IEEE Computer Society, 2015, s. 138-144Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The provision of quality of service for Wireless Sensor Networks is more relevant than ever now where wireless solutions with their flexibility advantages are considered for the extension/substitution of wired networks for a multitude of industrial applications. Scheduling algorithms that give end-to-end guarantees for both reliability and latency exist, but according to recent investigations is the achieved quality of service insufficient for most control applications. Data aggregation is an effective tool to significantly improve on end-to-end contention and energy efficiency compared to single packet transmissions. In practice, though, it is not extensively used for process data processing on the MAC layer. In this paper, we outline the challenges for the use of data aggregation in Industrial Wireless Sensor Networks. We further extend SchedEx, a reliability-aware scheduling algorithm extension, for packet aggregation. Our simulations for scheduling algorithms from the literature show its great potential for industrial applications. Features for the inclusion of data aggregation into industrial standards such as WirelessHART are suggested, and remaining open issues for future work are presented and discussed.

  • 10.
    Dobslaw, Felix
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    Tingting, Zhang
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Latency Improvement Strategies for Reliability-Aware Scheduling in Industrial Wireless Sensor Networks2015Inngår i: International Journal of Distributed Sensor Networks, ISSN 1550-1329, E-ISSN 1550-1477, artikkel-id 178368Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, we propose novel strategiesfor end-to-end reliability-aware scheduling in Industrial WirelessSensor Networks (IWSN). Because of stringent reliability requirements inindustrial applications where missed packets may have disastrous or lethalconsequences, all IWSN communication standards are based on TimeDivision Multiple Access (TDMA), allowing for deterministic channel access onthe MAC layer. We therefore extend an existing generic and scalablereliability-aware scheduling approach by name SchedEx. SchedEx has proven toquickly produce TDMA schedules that guarantee auser-defined end-to-end reliability level $\underline\rho$ for all multi-hopcommunication in a WSN. Moreover, SchedEx executes orders of magnitude fasterthan recent algorithms in the literature while producing schedules withcompetitive latencies.We generalize the original problem formulation from single-channel tomulti-channel scheduling and propose a scalable integration into the existingSchedEx approach.We further introduce a novel optimal bound that produces TDMAschedules with latencies around 20\% shorter than the original SchedExalgorithm. Combining the novel strategies with multiple sinks, multiplechannels, and the introduced optimal bound, we could through simulationsverify latency improvements by almost an order of magnitude, reducingthe TDMA super-frame execution times from tens of seconds to seconds only, whichallows for a utilization of SchedEx for many time-critical control applications.

  • 11.
    Dobslaw, Felix
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    A Reliability-Aware Cross-layer Optimization Framework for Wireless Sensor Networks.Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    One of the biggest obstacles for a broad deploymentof Wireless Sensor Networks for industrial applications is the dif-ficulty to ensure end-to-end reliability guarantees while providingas tight latency guarantees as possible. In response, we proposea novel centralized optimization framework for Wireless SensorNetworks that identifies TDMA schedules and routing combi-nations in an integrated manner. The framework is shown toguarantee end-to-end reliability for all events send in a schedulingframe while minimizing the delay of all packet transmissions. Itcan further be applied using alternative Quality of Service ob-jectives and constraints including energy efficiency and fairness.We consider network settings with multiple channels, multiplesinks, and stringent reliability constraints for data collectingflows. We compare the results to those achieved by the onlyscalable reliability-aware TDMA scheduling algorithm to ourknowledge, SchedEx, which conducts scheduling only. By makingrouting part of the problem and by introducing the conceptof source-aware routing, we achieve latency improvements forall topologies, with a notable average improvement of up to31percent.

  • 12.
    Dobslaw, Felix
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    End-to-End Reliability-aware Scheduling for Wireless Sensor Networks2016Inngår i: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 12, nr 2, s. 758-767Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wireless Sensor Networks (WSN) are gaining popularity as a flexible and economical alternative to field-bus installations for monitoring and control applications. For missioncritical applications, communication networks must provide endto- end reliability guarantees, posing substantial challenges for WSN. Reliability can be improved by redundancy, and is often addressed on the MAC layer by re-submission of lost packets, usually applying slotted scheduling. Recently, researchers have proposed a strategy to optimally improve the reliability of a given schedule by repeating the most rewarding slots in a schedule incrementally until a deadline. This Incrementer can be used with most scheduling algorithms but has scalability issues which narrows its usability to offline calculations of schedules, for networks that are rather static. In this paper, we introduce SchedEx, a generic heuristic scheduling algorithm extension which guarantees a user-defined end-to-end reliability. SchedEx produces competitive schedules to the existing approach, and it does that consistently more than an order of magnitude faster. The harsher the end-to-end reliability demand of the network, the better SchedEx performs compared to the Incrementer. We further show that SchedEx has a more evenly distributed improvement impact on the scheduling algorithms, whereas the Incrementer favors schedules created by certain scheduling algorithms.

  • 13.
    Dobslaw, Felix
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    QoS Assessment for Mission-critical Wireless Sensor Network Applications2013Inngår i: Proceedings - Conference on Local Computer Networks, LCN / [ed] Matthias Wählisch, IEEE Xplore , 2013, s. 663-666Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Wireless sensor networks (WSN) must ensure worst-case end-to-end delay and reliability guarantees for mission-critical applications.TDMA-based scheduling offers delay guarantees, thus it is used in industrial monitoring and automation. We propose to evolve pairs of TDMA schedule and routing-tree in a cross-layer in order to fulfill multiple conflicting QoS requirements,exemplified by latency and reliability.The genetic algorithm we utilize can be used as an analytical tool for both the feasibility and expected QoS in production. Near-optimal cross-layer solutions are found within seconds and can be directly enforced into the network.

  • 14.
    Dobslaw, Felix
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    QoS-Aware Cross-layer Configuration for Industrial Wireless Sensor Networks2016Inngår i: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 12, nr 5, s. 1679-1691, artikkel-id 7485858Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In many applications of Industrial Sensor Networks, stringentreliability and maximum delay constraints paired with priority demands ona sensor-basis are present. These QoS requirements pose tough challenges forIndustrial Wireless Sensor Networks that are deployed to an ever largerextent due to their flexibility and extendibility.In this paper, we introduce an integrated cross-layer framework, SchedEx-GA, spanning MAC layer and networklayer. SchedEx-GA attempts to identify a network configuration that fulfills all application-specific process requirements over a topology including the sensorpublish rates, maximum acceptable delay, service differentiation, and eventtransport reliabilities. The network configuration comprisesthe decision for routing, as well as scheduling.

    For many of the evaluatedtopologies it is not possible to find a valid configuration due to the physicalconditions of the environment. We therefore introduce a converging algorithm on top of the frameworkwhich configures a given topology by additional sink positioning in order tobuild a backbone with the gateway that guaranteesthe application specific constraints.The results show that, in order to guarantee a high end-to-end reliability of 99.999% for all flows in a network containing emergency, control loop, andmonitoring traffic, a backbone with multiple sinks is often required for thetested topologies. Additional features, such as multi-channel utilization andaggregation, though, can substantially reduce the demand for required sinks.In its present version, the framework is used for centralized control, butwith the potential to be extended for de-centralized control in future work.

  • 15.
    Gidlund, Mikael
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Yang, Dong
    Beijing Jiatong University.
    Xu, Youzhi
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Shen, Wei
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Wireless communication method and system with collision avoidance protocol2012Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    The invention concerns a method for providing wireless communication between a source node and a destination node in a wireless network wherein said wireless network uses a time division multiple access (TDMA) protocol. One or more dedicated TDMA transaction timeslots (60-71) are arranged in a superframe. The superframe comprises at least one dedicated transaction slot forming a hybrid protocol with two or more shared transaction slots 50 per superframe. The method is of particular advantage when practised with a WirelessHART protocol wireless sensor network and when used for monitoring and control equipment and processes in an industrial installation. A computer program, and a wireless node and a wireless network using the inventive method are also disclosed.

  • 16.
    Huang, X.
    et al.
    Department of Computer Science, University of Oxford, Oxford, United Kingdom.
    Fu, R.
    China Information Technology Security Evaluation Center, Beijing, China .
    Chen, B.
    Department of Computer Science, University of Oxford, Oxford, United Kingdom .
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Roscoe, A. W.
    Department of Computer Science, University of Oxford, Oxford, United Kingdom .
    User interactive Internet of things privacy preserved access control2012Inngår i: 2012 International Conference for Internet Technology and Secured Transactions, ICITST 2012, IEEE conference proceedings, 2012, s. 597-602Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The Internet of Things (IoT) is a network of objects; it is enabled by the Internet technologies. The IoT always collects sensitive data, but inadequate protection may lead to serious user privacy leakage. Thus, privacy protection functions are important to the IoT. Our research aims to provide better privacy protections to IoTs. Firstly, user controlled privacy preserved access control protocol is proposed. Secondly, context aware k-anonymity privacy policy and filter are designed. Thirdly, privacy protection mechanisms are investigated, and the privacy protection mechanisms are improved based on the investigation results. Therefore, users can control which of their personal data is being collected and accessed, who is collecting and accessing such data, and when these are happening. © 2012 Infonomics Society.

  • 17.
    Huang, Xin
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Jiang, Yang
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Gao, Xiong
    Gu, Rong
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Sensor Aided Authentication2010Inngår i: Communications in Computer and Information Science Volume 76 CCIS, 2010, Springer, 2010, s. 265-277Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The sharing of sensor data globally becomes possible by the development of wireless sensor network, cloud computing, and other related technologies. These new trends can also benefit information security. In this paper, the sensor data is involved in the authentication procedure which is one main component of security systems. Sensor aided password is proposed. In addition, the architecture for sensor aided authentication corresponding to the simple authentication scenario is also designed. Sensor data aided password generation and utilization bring convenience to users without weakening the password strength.

  • 18.
    Huang, Xin
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Jiang, Yang
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Kanter, Theo
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Privacy for mHealth Presence2010Inngår i: International Journal of Next-Generation Networks, ISSN 0975-7252, E-ISSN 0975-7023, Vol. 2, nr 4, s. 33-44Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    mHealth data provision focuses on providing health services to patients via mobile devices and presence technologies. It has great influence to the healthcare business today, especially in the developing countries. However, the mHealth presence might be sensitive; and it brings potential privacy issues. For controlling what presence information can be given to which watcher, and when in mHealth presence service, XML Configuration Access Protocol (XCAP) is introduced. Nevertheless, it is not enough if only XCAP is applied. It just controls the direct privacy leakage; indirect flow might still leak the privacy information. Thus, presence authorization policy and privacy filter, which are components of XCAP, are improved based on k-anonymity for stopping indirect privacy leakage.

  • 19.
    Huang, Xin
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Yin, He
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Yifan, Hou
    Lisi, Li
    Lan, Sun
    Sina, Zhang
    Yang, Jiang
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Privacy of Value-Added Context-Aware Service Cloud2009Inngår i: Lecture notes in computer science Volume 5931, Springer, 2009, Vol. 5931, s. 547-552Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In the cloud computing era, service provider cloud and context service cloud store all your personal context data. This is a positive aspect for value-added context-aware service cloud as it makes that context information collection are easier than was the case previously. However, this computing environment does add a series of threats in relation to privacy protection. Whoever receives the context information is able to deduce the status of the owners and, generally owners are not happy to share this information. In this paper, we propose a privacy preserved framework which can be utilized by value-added context-aware service cloud. Context data and related services access privileges are determined by context-aware role-based access control (CRAC) extended from role-based access control (RAC). Privacy preserved context service protocol (PPCS) is designed to protect user privacy from exposed context information. Additionally, user network and information diffusion is combined to evaluate the privacy protection effect.

  • 20.
    Huang, Xin
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Privacy and Security Aware Home Sensor System2010Inngår i: 2010 Cross-Strait Conference on Information Science and Technology, CSCIST 2010, Qinghuangdao, China, July, 2010, Scientific Research Publishing, 2010Konferansepaper (Fagfellevurdert)
  • 21. Huang, Xin
    et al.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Hou, Yifan
    ID management among clouds2009Inngår i: 2009 1st International Conference on Future Information Networks, ICFIN 2009, IEEE conference proceedings, 2009, s. 237-241Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In the following years, the desktop-based applications will be changed to cloud computing gradually. Since all users' profile and context data will be stored on the service supplier side based on their ID. ID is becoming a security bottleneck: attackers can trace all other information via user ID. Increasingly, a simple service may be involved in a chain of service clouds; each cloud is able to access data in its cloud without the control of any technology. With ID and password cross utilization in clear text, leakage of ID profile and password in one cloud may propagate to the whole cloud chain. Without proper protection, the success of cloud computing will be threatened by ID privacy leakage. In this paper, privacy preserved ID profile utilizing protocol (PPID) is proposed to prevent this privacy flaw. PPID together with its extension ID anonymity protocol (IDA) separate ID and services. With these two protocols, threaten from crash of whole cloud chain caused by ID privacy leakage is minimized.

  • 22.
    Huang, Xin
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Sun, Lan
    Outer System Flow Privacy Protection2010Inngår i: 2010 IEEE International Systems Conference Proceedings, SysCon 2010, IEEE conference proceedings, 2010, s. 117-120Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Nowadays, social networks, information networks and technological networks have already become main media of information publication and exchange. Meanwhile, the information diffusion in these networks is well studied. However, most privacy protection technologies, e.g., access control, have not considered the influence of these networks systematically. In this paper, a concept of outer system flow privacy control is proposed. In addition, system privacy requirements are reconsidered. Furthermore, in user case, role base access control (RBAC) is analyzed and improved based on the outer system flow control

  • 23.
    Jennehag, Ulf
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Increasing bandwidth utilization in next generation IPTV networks2004Inngår i: ICIP: 2004 INTERNATIONAL CONFERENCE ON IMAGE PROCESSING, VOLS 1- 5, IEEE conference proceedings, 2004, s. 2075-2078Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper we present a novel idea regarding transmission of next generation IPTV content. Today IPTV systems utilize a COP structure tu provide stream synchronization points for the clients, these are used when a channel switch occur. Since channel switches made by TV audiences are quite rare it is redundant to send synchronization opportunities in a GOP manner. The proposed design, synchronization frames fur channel switching (SFCS), only requests synchronization frames when needed. We present a network traffic analysis model and compare it with simulations. SFCS increases bandwidth utilization compared to traditional COP system under the presented transmission environment.

  • 24.
    Jennehag, Ulf
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Pettersson, Stefan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Improving transmission efficiency in H.264 based IPTV systems2007Inngår i: IEEE transactions on broadcasting, ISSN 0018-9316, E-ISSN 1557-9611, Vol. 53, nr 1, s. 69-78Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this paper, a novel proposal regarding the transmission of the next generation of live-TV content in an IPTV environment is presented. Today live-TV IP transmission systems utilizes a Group Of Pictures (GOP) structure in order to provide stream synchronization points for the clients. Synchronization points are used when a TV-channel switch occurs. The number of channel switches made by TV audiences have been shown to be rather rare. It is therefore redundant to send synchronization events in a GOP manner. Our proposal, Synchronization Frames for Channel Switching (SFCS), only requests synchronization points when required. Due to channel popularity distributions and the number of connected users, the total number of synchronization requests for a popular channel can increase to a level that makes SFCS less effective than GOP. Therefore, we introduce an SFCS-GOP hybrid. A complete network traffic analysis model, verified by a simple simulation environment, is also presented and the results show that the SFCS-GOP hybrid significantly increases the bandwidth utilization compared to a traditional GOP system

  • 25.
    Lavassani, Mehrzad
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Barac, Filip
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Handling Event-Triggered Traffic of Safety and Closed-Loop Control Systems in WSANs2016Inngår i: 14th IEEE International Conference on Industrial Informatics (INDIN'16), IEEE, 2016, s. 631-636, artikkel-id 7819237Konferansepaper (Fagfellevurdert)
  • 26.
    Lavassani, Mehrzad
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Forsström, Stefan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Jennehag, Ulf
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Combining Fog Computing with Sensor Mote Machine Learning for Industrial IoT2018Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 18, nr 5, artikkel-id 1532Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Digitalization is a global trend becoming ever more important to our connected and sustainable society. This trend also affects industry where the Industrial Internet of Things is an important part, and there is a need to conserve spectrum as well as energy when communicating data to a fog or cloud back-end system. In this paper we investigate the benefits of fog computing by proposing a novel distributed learning model on the sensor device and simulating the data stream in the fog, instead of transmitting all raw sensor values to the cloud back-end. To save energy and to communicate as few packets as possible, the updated parameters of the learned model at the sensor device are communicated in longer time intervals to a fog computing system. The proposed framework is implemented and tested in a real world testbed in order to make quantitative measurements and evaluate the system. Our results show that the proposed model can achieve a 98% decrease in the number of packets sent over the wireless link, and the fog node can still simulate the data stream with an acceptable accuracy of 97%. We also observe an end-to-end delay of 180 ms in our proposed three-layer framework. Hence, the framework shows that a combination of fog and cloud computing with a distributed data modeling at the sensor device for wireless sensor networks can be beneficial for Industrial Internet of Things applications.

  • 27.
    Lin, Yeqiang
    et al.
    Donghua Univ, Dept Comp Sci & Technol, Shanghai, Peoples R China.
    Lavassani, Mehrzad
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Li, Jiyun
    Donghua Univ, Dept Comp Sci & Technol, Shanghai, Peoples R China.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    PixVid: Capturing Temporal Correlated Changes in Time Series2017Inngår i: Proceedings - 5th International Conference on Advanced Cloud and Big Data, CBD 2017, 2017, s. 337-342, artikkel-id 8026960Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Time series is one of the main research domains in variety of disciplines. Visualization is an important mechanism to present the raw data as well as the processed time series for further analysis. Many successful visualization techniques have been reported recently. However, most of these techniques display data statically, intending to show as much information as possible by one image or plot. We propose PixVid, a visualization technique which orders the dimensions by constructing a hierarchal dimension cluster tree, and then uses a pixel-oriented technique to form images and displays the data in video format.

  • 28.
    Lindén, Johannes
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Forsström, Stefan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Evaluating Combinations of Classification Algorithms and Paragraph Vectors for News Article Classification2018Inngår i: Proceedings of the 2018 Federated Conference on Computer Science and Information Systems / [ed] Maria Ganzha, Leszek Maciaszek, Marcin Paprzycki, Warzaw: Polskie Towarzystwo Informatyczne , 2018, s. 489-495, artikkel-id 8511213Konferansepaper (Fagfellevurdert)
    Abstract [en]

    News companies have a need to automate and make the process of writing about popular and new events more effective. Current technologies involve robotic programs that fill in values in templates and website listeners that notify editors when changes are made so that the editor can read up on the source change on the actual website. Editors can provide news faster and better if directly provided with abstracts of the external sources and categorical meta-data that supports what the text is about. In this article, the focus is on the importance of evaluating critical parameter modifications of the four classification algorithms Decisiontree, Randomforest, Multi Layer perceptron and Long-Short-Term-Memory in a combination with the paragraph vector algorithms Distributed Memory and Distributed Bag of Words, with an aim to categorise news articles. The result shows that Decisiontree and Multi Layer perceptron are stable within a short interval, while Randomforest is more dependent on the parameters best split and number of trees. The most accurate model is Long-Short-Term-Memory model that achieves an accuracy of 71%.

  • 29.
    Lindén, Johannes
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi.
    Wang, Xutao
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi.
    Forsström, Stefan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi.
    Bilingual Auto-Categorization Comparison of two LSTM Text Classifiers2019Konferansepaper (Annet vitenskapelig)
  • 30.
    Lu, Xuchen
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Tang, Hongling
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Cheng, Wenli
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Heterogeneous Data Source Middleware for Android E-Health Application2012Inngår i: 2012 EIGHTH INTERNATIONAL CONFERENCE ON MOBILE AD HOC AND SENSOR NETWORKS (MSN 2012), 2012, s. 92-99Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Heterogeneous data sources management is a big challenge for complex projects, especially in the situation of sensor net work. The incompatibility of different data sources makes it complicated for a project to modify databases in use or adapt to new sensors. In this paper, we propose a middleware solution to address the problem. The middleware uses an abstract class to shield the differences among heterogeneous data sources and creates a data source service wrapper for each. Both permanent data info and real-time data flows should pass through the middleware during communication of data sources and application. And by implementing a corresponding data source service wrapper, it's very convenient to add a new data source. At the same time, the middleware uses XML to accomplish data mapping and transmission, so as to solve the incompatibility of data sources schema and ensure platform independence. We deployed the middleware to our E-Health project. Our experience has proved the flexibility and extensibility of the middleware.

  • 31.
    Malmberg, Åke
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Intelligent agents for information retreival in internet1997Inngår i: Artificial intelligence and soft computing : proceedings of the IASTED international conference, Banff, Canada, July 27 to August 1, 1997, Anaheim, Calif.: IASTED/ACTA Press , 1997, s. 327-330Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Building intelligent software agents using traditional knowledge acquisition methods is difficult because of the dynamic properties of Internet. Knowledge about Internet can be divided in two levels. The first level is knowledge about tools and methods for searching information in Internet. The second level is knowledge about information in Internet (meta level). We focus on the meta level. Our approach is to identify knowledge sources in Internet. The knowledge may be implemented in a software agent and the planning can be improved by combining the knowledge from several intelligent software agents.

  • 32.
    Marx, B.
    et al.
    Fachhochschule Osnabrueck.
    Kollecker, J.
    Fachhochschule Osnabrueck.
    Lammen, B.
    Fachhochschule Osnabrueck.
    Nordin, J.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Sjöström, Mårten
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Distributed Vehicle Simulation - A Student Project in Mechatronics and Distributed Systems2008Inngår i: 9th International Workshop on Research and Education in Mechatronics, Bergamo, Italy, 18-19 September 2008., 2008Konferansepaper (Annet vitenskapelig)
  • 33. Olsson, K
    et al.
    Andersson, Roger
    Zhang, TingTing
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Xu, Youshi
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    A Fast Implementation Scheme for 2-D Discrete Cosine Transform1997Patent (Annet (populærvitenskap, debatt, mm))
  • 34. Olsson, K
    et al.
    Andersson, Roger
    Zhang, TingTing
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Xu, Youshi
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Digital Video Temporal Noise Reduction1997Patent (Annet (populærvitenskap, debatt, mm))
  • 35.
    Padghalm, Lin
    et al.
    IDA, Linköping University.
    Zhang, Tingting
    IDA, Linköping University.
    Building the Ontology for a Medical Diagnosis System Using Standard Text1995Inngår i: In the IJCAI’95 Workshop ”Basic Ontological Issues in Knowledge Sharing, Canada, 1995Konferansepaper (Fagfellevurdert)
  • 36.
    Padghalm, Lin
    et al.
    IDA, Linköping University.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Terminological Logic with Defaults: A definition and an Application1993Inngår i: Proceedings of IJCAI'93, France, 1993Konferansepaper (Annet vitenskapelig)
  • 37.
    Peng, Yingli
    et al.
    Donghua University, Shanghai, China.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. STC.
    Sun, Li
    Donghua University, Shanghai, China.
    Chen, Jie
    Donghua University, Shanghai, China.
    A Novel Data Mining Method on Falling Detection and Daily Activities Recognition2015Inngår i: Proceedings - International Conference on Tools with Artificial Intelligence, ICTAI, IEEE Computer Society, 2015, s. 675-681, artikkel-id 7372198Konferansepaper (Fagfellevurdert)
    Abstract [en]

    With the intensification of aging population, a growing number of elderly people have to live alone due to domestic and social reasons. Falling becomes one of the most crucial factors in threatening the elderly's lives, which is always difficult to be detected as it is instantaneous and easy to be confused with other motions, such as lying down. In this paper, a new method is proposed for accurate falling detection and activities recognition. It applies hierarchical classifiers to the time series data set including eleven activities of daily living (ADLs), collected by four wearable sensors. The new method combines two machine learning algorithms, performs concrete analysis on the original outcome and then obtains several scarcely-confused groups separately. The experiment indicates that the new method improves the accuracy of classification to a larger extent, reached to more than 90%. Furthermore, the matched algorithm for applying these classifiers, called Hierarchical Classifier Algorithm (HCA), is proposed as well.

  • 38.
    Reiman, Ulf
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Pettersson, Stefan
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    A secure multicast downstream authentication protocol in sensor network2007Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A secure multicast downstream authentication protocol in sensor network: we develop a authentication protocol for sensor networks where the transmitted data is protected by algorithms� for privacy and authentication

  • 39.
    Shen, Wei
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    Barac, Filip
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap. ABB Corporate Research, SE-72178 Vasteras, Sweden.
    PriorityMAC: A Priority-Enhanced MAC Protocol for Critical Traffic in Industrial Wireless Sensor and Actuator Networks2014Inngår i: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 10, nr 1, s. 824-835Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper proposes PriorityMAC, a priority-enhanced medium access control protocol, designed for critical traffic in industrial wireless sensor and actuator networks (IWSAN). A notable trend in industrial automation in recent years has been the replacement of wired communication by IWSANs. Exceeding the required delay bound for unpredictable and emergency traffic could lead to system instability, economic and material losses, system failure, and, ultimately, a threat to human safety. Guaranteeing the timely delivery of the IWSAN critical traffic and its prioritization over regular traffic (e.g., noncritical monitoring traffic) is a significant challenge. Therefore, we present the design, implementation, performance analysis, and evaluation of PriorityMAC. A series of novel mechanisms (e.g., high priority indication space) are proposed to enable high-priority traffic to hijack the transmission bandwidth of the low-priority traffic. To the best of our knowledge, this is the first priority-enhanced MAC protocol compatible with industrial standards for IWSAN. PriorityMAC is implemented in TinyOS and evaluated on a testbed of Telosb motes. The experimental results indicate that PriorityMAC efficiently handles different traffic categories with different latency requirements, thereby achieving a significant improvement in the delivery latency compared with the current industrial standards. © 2005-2012 IEEE.

  • 40.
    Shen, Wei
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Gidlund, Mikael
    ABB Corporate Research.
    Distributed Data Gathering Scheduling Protocol for Wireless Sensor Actor and Actuator Networks2012Inngår i: Communications (ICC), 2012 IEEE International Conference on, IEEE Communications Society, 2012, s. 7120-7125Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents a cross-layer distributed scheduling protocol for sensor data gathering transmission inwireless sensor actor and actuator networks. We propose the parent-dominant decision scheduling with collision free (PDDS-CF) algorithm to adapt the dynamics of links in a realistic low-power wireless network. In addition, the protocol has a light-weight mechanism to maintain the conflict links. We have evaluated the protocol andimplementation in TinyOS and Telosb hardware. The experiment shows that our protocol has robustness to the topology changes and it has significant improvements to reduce the traffic load in realistic wireless networks.

  • 41.
    Shen, Wei
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Joint Routing and MAC for Critical Traffic in Industrial Wireless Sensor and Actuator Networks2013Inngår i: IEEE International Symposium on Industrial Electronics, 2013, s. Art. no. 6563730-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper proposes Delay Bounded Routing (DBR) and a Priority-based Medium Access Control method (PriorityMAC), designed for routing critical traffic in Industrial Wireless Sensor and Actuator Networks (IWSAN). A notable trend in industrial automation in recent years is the replacement of wired communication with IWSAN. Exceeding the required delay bound for unpredictable and emergency traffic could lead to system instability, economic and material losses, system failure and, ultimately, a threat to human safety. Guaranteeing the timely delivery of the critical traffic and its prioritization over regular traffic (e. g. non-critical monitoring traffic) is a significant challenge. Therefore, we present the design, implementation and evaluation of DBR and PriorityMAC. DBR and PriorityMAC are implemented in TinyOS and evaluated on a testbed of Telosb motes. The experimental results indicate that our protocol achieves a significant improvement of the end-to-end delivery latency compared to the current industrial standards.

  • 42.
    Shen, Wei
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. ABB Corp Res, Vasterås, Sweden.
    Dobslaw, Felix
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
    SAS-TDMA: A Source Aware Scheduling Algorithm for Real-Time Communication in Industrial Wireless Sensor Networks2013Inngår i: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 19, nr 6, s. 1155-1170Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Scheduling algorithms play an importantrole for TDMA-based wireless sensor networks. ExistingTDMA scheduling algorithms address a multitude of objectives.However, their adaptation to the dynamics of a realistic wirelesssensor network has not been investigated in a satisfactorymanner. This is a key issue considering the challenges withinindustrial applications for wireless sensor networks, given thetime-constraints and harsh environments.In response to those challenges, we present SAS-TDMA, asource-aware scheduling algorithm. It is a cross-layer solutionwhich adapts itself to network dynamics. It realizes a tradeoffbetween scheduling length and its configurational overheadincurred by rapid responses to routes changes. We implementeda TDMA stack instead of the default CSMA stack and introduceda cross-layer for scheduling in TOSSIM, the TinyOS simulator.Numerical results show that SAS-TDMA improves the qualityof service for the entire network. It achieves significant improvementsfor realistic dynamic wireless sensor networks whencompared to existing scheduling algorithms with the aim tominimize latency for real-time communication.

  • 43.
    Shen, Wei
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Xu, Youzhi
    Computer and Electrical Engineering Department, School of Engineering, Jönköping University, Jönköping, Sweden.
    Xie, Donghua
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Johansson, Alf
    Computer and Electrical Engineering Department, School of Engineering, Jönköping University, Jönköping, Sweden.
    Smart Border Routers for eHealthCare Wireless Sensor Networks2011Inngår i: The 7th International Conference on Wireless Communications, Networking and Mobile Computing (WiCOM), IEEE conference proceedings, 2011, s. 1-4Konferansepaper (Fagfellevurdert)
    Abstract [en]

    With advances in low-power and low-cost wireless and sensor technologies, using WSNs in eHealthCare system has yielded tremendous efforts in recent years. However, most of previous researches adopt a remote server to process large scale of health sensor data forwarded by gateways that allow for interconnecting WSNs to IP network. In this paper, we present a prototype of a smart 6LoWPAN border router aimed to locally make decisions of health states using a Hidden Markov Model and enable wireless E-health care sensor network to seamlessly connect with IP network.

  • 44.
    Tang, Jun
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Mid Sweden University: A survey of wireless sensor networks for home healthcare monitoring application2013Inngår i: SENSORNETS 2013 - Proceedings of the 2nd International Conference on Sensor Networks, 2013, s. 240-243Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In recent years, wireless sensor network technology has become mature. Working together with biomedical engineering, it has enormous potential benefits to improve the lifestyle of human especially for the elderly. This survey mainly focuses on two prototypes of home healthcare monitoring application: daily activities monitoring application and medical status monitoring application. It will present the requirement analysis which starts from the causes of chronic diseases. The paper also discusses challenges for current home healthcare monitoring application. At the last part of the survey, it will give the conclusion and future aspects.

  • 45.
    Wang, Biying
    et al.
    University of Jyväskylä, Jyväskylä, Finland.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
    Chang, Zheng
    University of Jyväskylä, Jyväskylä, Finland.
    Ristaniemi, Tapani
    University of Jyväskylä, Jyväskylä, Finland.
    Liu, Guohua
    Donghua University, Shanghai, China.
    3D Matrix-Based Visualization System of Association Rules2017Inngår i: IEEE CIT 2017 - 17th IEEE International Conference on Computer and Information Technology, IEEE, 2017, s. 357-362, artikkel-id 8031499Konferansepaper (Fagfellevurdert)
    Abstract [en]

    With the growing number of mining datasets, it becomes increasingly difficult to explore interesting rules because of the large number of resultant and its nature complexity. Studies on human perception and intuition show that graphical representation could be a better illustration of how to seek information from the data using the capabilities of human visual system. In this work, we present and implement a 3D matrix-based approach visualization system of association rules. The main visual representation applies the extended matrix-based approach with rule-to-items mapping to general transaction data set. A novel method merging rules and assigning weight is proposed in order to reduce the dimension of the association rules, which will help users to find more important items in the new rule. Furthermore, several interactions such as sorting, filtering, zoom and rotation, facilitate decision-makers to explore the rules which are of interest in various aspects. Finally, extensive evaluations have been conducted to assess the system from a logical reasoning point of view. 

  • 46.
    Wang, Q.
    et al.
    Department of Electronics, Telecommunications Norwegian University of Science and Technology, Trondheim N-7491, Norway.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Balasingham, I.
    Department of Electronics, Telecommunications Norwegian University of Science and Technology, Trondheim N-7491, Norway.
    Characterizing the traffic load distribution in dense wireless sensor networks2011Inngår i: Journal of Networks, ISSN 1796-2056, E-ISSN 1796-2056, Vol. 6, nr 2, s. 173-180Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Traffic load is typically not evenly distributed over the sensor nodes in a wireless sensor network (WSN). Understanding the traffic load distribution can guide the network-wide energy allocation, the design of routing algorithms, and the optimization of the node deployment in WSNs. This article considers a dense WSN with nodes uniformly distributed in a disk sensing area, where the expected traffic load distribution over the sensor nodes as a function of their distance from the sink has been derived. Further, the effects of the network scale and routing strategy on traffic load distribution are also investigated. The expected traffic loads beared by individual sensor nodes are found to be in direct proportion to the radius of the network and inversively proportional to the routing hop length but it is independent of the network density. In addition, a heuristic multipath routing algorithm is found to be capable of reducing the traffic load variance experienced by neighboring or symmetrically deployed sensor nodes. The results presented in this article are verified through extensive simulation experiments. © 2011 ACADEMY PUBLISHER.

  • 47.
    Wang, Qinghua
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    A Multi-homing Extension of Wireless Node Implementation in Ns-22009Inngår i: 2009 4th International Conference on Communications and Networking in China, CHINACOM 2009: ChinaCom'09, IEEE conference proceedings, 2009, s. 751-756Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Due to the rapid growth of wireless communication, it is now believed that wireless devices with multiple interface support will highly increase in the near future. In the research community of Network Simulator, there has recently been quite a large interest in extending the current wireless node implementation so as to be able to include more than one radio interface to work simultaneously.

    We focus our efforts on the extension of multi-homing ability of ns-2, which has been the most used network simulator in wireless network research. Multi-homing here is defined as the ability of a single end-point to support multiple IP addresses by the use of multiple interfaces. The ns-2 simulation environment is a flexible tool for network engineers to investigate how various protocols perform with different configurations and topologies. However, the support for wireless and mobile networking in ns-2 is monolithic and not entirely consistent with basic design principles so that it makes it quite difficult, if not impossible, to extend a multi-homing support based on current mobilenode design. This paper describes how we extend the ns-2 framework to include support for an imititated wireless multi-homed node.

  • 48.
    Wang, Qinghua
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    A Survey on Security in Wireless Sensor Networks2009Inngår i: Security in RFID and Sensor Networks, Boca Raton: CRC Press, 2009, s. 293-320Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    Recent advances in electronics and wireless network technologies have offered us access to a new era where wireless sensor networks formed by inter-connected small intelligent sensing devices provide us the possibility to form smart environments. Considering the specialty of wireless sensor network, the security threats and possible countermeasures are quite different from those in Internet and Mobile Ad Hoc Networks (MANETs). On the one hand, the wireless communication, large scale and possibly human unattended deployment make attacks in wireless sensor networks relatively easier to perform. Furthermore, all features that make sensor nodes cheap and thus sensor network application affordable, such as limited energy resource, limited bandwidth and limited memory, also make many well-developed security mechanisms inappropriate in sensor networks. On the other hand, the user unfriendly interface makes the physical compromise of a sensor node difficult, the relatively simple communication profile makes the intrusion detection easy to perform, and also the redundant deployment makes the new type of network more fault-tolerant. Thus, we need a complete redesign of sensor network security mechanisms from technique to management.

  • 49.
    Wang, Qinghua
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Bottleneck Zone Analysis in Energy-Constrained Wireless Sensor Networks2009Inngår i: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 13, nr 6, s. 423-425Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In a typical sensor network, nodes around the sink bear more energy consumption than those further away. It is not unusual that limited energy resources available at the nodes around the sink become the bottleneck which confines the whole network's performance. In this article, we firstly formally define the so-called bottleneck zone inside sensor networks. Then, the effect of the bottleneck zone on network performance is investigated by deducting performance bounds limited by the energy resources available inside the bottleneck zone. In this article, both the performance bound in terms of network lifetime and the performance bound in terms of information collection are explored. Finally, the ways by which network deployment parameters may affect the performance bounds are analyzed.

  • 50.
    Wang, Qinghua
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Characterizing the traffic load distribution in dense sensor networks2009Inngår i: 3rd International Conference on New Technologies, Mobility and Security, NTMS 2009, IEEE conference proceedings, 2009, s. 5384829-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Traffic load is not evenly distributed over the nodes in a wireless sensor network (WSN). Understanding the traffic load distribution can guide the network-wide energy allocation, direct the design of routing algorithms, and optimize the node deployment in WSNs. In this paper, we consider a dense WSN with nodes uniformly distributed in a disk sensing area, and find the traffic load distribution over the nodes as a function of their distance from the sink. Further, the effects of network scale and routing strategy on traffic load are also investigated. The traffic loads on individual nodes are found to be in direct proportion to the radius of the network and in inverse proportion to the routing hop distance, while independent of network density. The results presented in this paper are verified through extensive simulation experiments.

12 1 - 50 of 87
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf