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  • 351.
    Bååth, L.B.
    et al.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    Rogers, A.E.E.
    Haystack Observatory, Westford, MA, USA.
    Inoue, M.
    Nobeyama Radio Observatory, Nobeyama, Minamisaku, Nagano, Japan.
    Padin, S.
    Owens Valley Observatory, Pasadena, CA, USA.
    Wright, M.C.H.
    University of California, Berkeley, CA, USA.
    Zensus, A.
    National Radio Astronomy Observatory, Socorro, NM, USA.
    Kus, A.J.
    Torun Radio Observatory, Torun, Poland.
    Backer, D.C.
    University of California, Berkeley, CA, USA.
    Booth, R.S.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    Carlstrom, J.E.
    University of California, Berkeley, CA, USA.
    Dickman, R.L.
    University of Massachusetts, AMherst, MA, USA.
    Emerson, D.T.
    National Radio Astronomy Observatory, Tucson, AZ, USA.
    Hirabayashi, H.
    Nobeyama Radio Observatory, Nobeyama, Minamisaku, Nagano, Japan.
    Hodges, M.W.
    Owens Valley Observatory, Pasadena, CA, USA.
    Kobayashi, H.
    Nobeyama Radio Observatory, Nobeyama, Minamisaku, Nagano, Japan.
    Lamb, J.
    National Radio Astronomy Observatory, Tucson, AZ, USA.
    Moran, J.M.
    Center for Astrophysics, Cambridge, MA, USA.
    Morimoto, M.
    Nobeyama Radio Observatory, Nobeyama, Minamisaku, Nagano, Japan.
    Plambeck, R.L.
    University of California, Berkeley, CA, USA.
    Predmore, C.R.
    University of Massachusetts, AMherst, MA, USA.
    Rönnäng, B.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    Woody, D.
    Owens Valley Observatory, Pasadena, CA, USA.
    VLBI observations of active galactic nuclei at 3 MM1992In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 257, no 1, p. 31-46Article in journal (Refereed)
    Abstract [en]

    Recent improvements in data analysis and receiver techniques have allowed us to produce maps of the 100 GHz emission from the compact cores of active galactic nuclei with the unsurpassed resolution of 50-mu-as (microarcseconds). We present here hybrid maps of a set of compact radio sources observed at two epochs with a global VLBI array. The high resolution enables us to show details of active galactic nuclei on size scales of 10(16)-10(17) cm. Jets are shown to be more curved in these inner parts than further out in the areas mapped with VLBI at lower frequencies. Our maps of the quasar 3C345 show that the curvature seen with lower resolution instruments continues very close to the core. New components are seen separating from the cores of 3C84 and BL Lac. We observe a component in 3C84 separating from the core with an apparent speed approximately 21000 km sec-1. The radio source OJ287 is still unresolved with our array, having a core size of less-than-or-similar-to 10(17) cm. There is no indication of any compact component in 3C279 which would be associated with the outburst in integrated flux density which happened some months before our observation. The flux density of the most compact component we observe in 3C279 agrees well with that of the quiet core as extrapolated from its radio spectrum at lower frequencies. The inner part of the radio jet of the giant elliptical galaxy M87 also shows a continuation of the structure on a larger size scale, with a structure we interpret as parts of a helical pattern. No fringes were found for 4C39.25 or Sgr A.

  • 352.
    Bååth, L.B.
    et al.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    Rönnäng, B.O.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    Pauliny-Toth, I.I.K.
    Max-Planck-Institut für Radioastronomie, Bonn, Germany.
    Kellermann, K.I.
    Max-Planck-Institut für Radioastronomie, Bonn, Germany.
    Preuss, E.
    Max-Planck-Institut für Radioastronomie, Bonn, Germany.
    Witzel, A.
    Max-Planck-Institut für Radioastronomie, Bonn, Germany.
    Matveenko, L.I.
    Space Research Institute, Moscow, USSR.
    Kogan, L.R.
    Space Research Institute, Moscow, USSR.
    Kostenko, V.I.
    Space Research Institute, Moscow, USSR.
    Moiseev, I.G.
    Crimean Astrophysical Observatory, USSR Academy of Sciences, P/O Nauchny, Crimea, USSR.
    Shaffer, D.B.
    National Radio Astronomy Observatory, Goddard Space Flight Center, Greenbelt, MD, USA.
    High Resolution Observations of the QSO 3C 345 at 1.3 centimeters1981In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 243, p. L123-L126Article in journal (Refereed)
    Abstract [en]

    High-resolution VLBI observations made at a frequency of 22.235 GHz of the quasar 3C 345 are discussed. Antennas located at the Crimean Astrophysical Observatory, USSR; Onsala, Sweden; Effelsberg, West Germany; and the Haystack Observatory, Massachusetts were employed at 4-min integration times to provide baselines ranging up to 5.5 x 10 to the 8th wavelengths. About 40% of the total flux density of 7.85 Jy, observed in November 1977, and 8.05 Jy, observed in October 1978, is found to originate in an unresolved component of the quasar core in a region less than 0.1 milliarcsec in diameter. The elongated jet-like component of the quasar is observed to contain several peaks of emission extending up to 6 milliarsec from the core which decreased in extent between the two observations.

  • 353.
    Bååth, L.B.
    et al.
    Onsala Space Observatory, Onsala, Sweden.
    Zhang, F. J.
    Shanghai Observatory, China.
    IMAGES OF THE BL LACERTAE OBJECT 1749+701 AT 5 GHZ1992In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 262, no 1, p. 1-7Article in journal (Refereed)
    Abstract [en]

    This paper presents images of 1749+701 from data obtained between 1980 and 1983 as a part of our VLBI programme to monitor a subsample of BL Lac objects at 5GHz. Our images show that this source has a complex structure with a jet pointing towards the north-west at a position angle of about -65-degrees. The brightest component is growing in extension along this position angle. We suggest this to be the core and that the growing extension was caused by a shock generated during an outburst and moving out along the jet. From the extension rate, we obtain an angular separation speed of 0.18 mas yr-1, which corresponds to an apparent transverse speed of 5c. The distances and position angles of two outer components seem remarkably constant. The phenomenon can be understood through a model in which a relativistic jet bends such that its axis is very close to the line of sight in two points. We also deduce that the Lorentz factor must be 4.5 less-than-or-equal-to gamma less-than-or-equal-to 6.5 and that the viewing angle must be 5-degrees less-than-or-equal-to theta less-than-or-equal-to 10-degrees. In this paper, we also present two images obtained from 5GHz MERLIN and combined MERLIN-VLBI data respectively. These maps show that there is a weak component located at a distance of 0.42 arcsec from the core at p.a -155-degrees.

  • 354.
    Bååth, L.B.
    et al.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    Zhang, F. J.
    Nuffield Radio Astronomy Laboratories, Jodrell Bank, Macclesfield, Cheshire, United Kingdom.
    Chu, H. S.
    Purple Mountain Observatory, Nanjing, China.
    0735+178: The cosmic conspiracy1991In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 250, no 1, p. 50-56Article in journal (Refereed)
    Abstract [en]

    This paper discusses a radio outburst in the BL Lac-object 0735+178 which started in early 1988, ended during 1990 and was succeeded by a new outburst which is still in progress. Our image obtained with a global VLBI network shows the source to mainly consist of a core-jet like structure ending in diffuse emission region of low surface brightness located to the east of the core. We identify two new components as having been produced during the late 1980's. They are moving out with apparent superluminal motion in a viewing angle of greater-than-or-similar-to 10-degrees at a distance of less-than-or-similar-to 2 mas from the core. The core includes another new component, but our resolution is just sufficient to resolve out this component from the core at our epoch of observation. We suggest that the weak emission region is caused by an older component reaching the point at which the Doppler boosting is at its maximum and that the long time scale flux variation are due to successive events when evolved components reach that point.

  • 355.
    Bååth, L.B.
    et al.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    Zhang, F.J.
    Onsala Space Observatory, Chalmers University of Technology, Gothenburg, Sweden.
    The radio fine structure of the BL Lacertae object 0735 + 1781991In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 243, no 2, p. 328-332Article in journal (Refereed)
    Abstract [en]

    The BL Lacertae object 0735 + 178 has been mapped with global VLBI arrays at four epochs from 1979 to 1983. The hybrid maps presented in this paper show a complex structure with a component separating from the core with an apparent transverse velocity of almost-equal-to 7.9 c. We suggest a model in which new components are born in the core during an outburst, initially move away towards northeast and then at a distance of almost-equal-to 4.2 mas turn towards the southeast. At this point, the component does not show any discernible motion away from the core. We suggest that the jet curls towards the south and towards the observer and at this point has its minimum viewing angle, with maximum boosting and minimum apparent velocity. We associate the outburst of 1989 with the event when a superluminally moving component reaches this point.

  • 356.
    Böcker, Helena
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Lind, Paulina
    Halmstad University, School of Business, Engineering and Science.
    Industrihampa -hinder och drivkrafter för en utökad och kommersiell odling i Sverige2019Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Klimatförändringarna är en av vår tids största miljöproblem. Kött är det livsmedel som ger störst klimatpåverkan då ca 70 procent av de grödor som odlas används som djurfoder och idisslande djur släpper ut metan. Nästan en femtedel av de globala utsläppen av växthusgaser kommer från animalieproduktion. Betesdjur är dock avgörande för att nå de nationella miljömålen ”Ett rikt odlingslandskap” och ”Ett rikt växt- och djurliv”. Industrihampa är en gröda som kan användas som proteinfodertillskott och för att minska metangasbildningen under matspjälkningsprocessen hos idisslare. Hampan har också stora möjligheter att bidra positivt till att nå ett flertal av de andra nationella miljömålen då den kan ersätta fossila råvaror inom energi, bygg- och tillverkningsindustrin samt minska behovet av mineralgödsel i jordbruket. Syftet med detta examensarbete är att undersöka vilka hinder och drivkrafter som finns för en utökad och kommersiell hampaproduktion i Sverige. Genom att även undersöka om odling och användning av industrihampa ur ett kretsloppsperspektiv kan vara en del av lösningen i att bromsa klimatförändringarna, avser arbetet att förmedla kunskap om hur industrihampa kan minska klimatpåverkan från köttdjursuppfödning i Sverige och bidra till uppfyllandet av flera nationella miljömål. En litteraturstudie har gjorts för att få en djupare kunskap om problematiken kring klimatförändringar kopplat till lantbruk och köttdjursuppfödning samt för att bättre förstå hur industrihampa skulle kunna motverka detta. Intervjuer har utförts med hampaodlare, andra lantbrukare, intresseorganisationer och myndigheter för att samla in data om orsakerna till att odlingen av hampa i Sverige är så begränsad. Resultaten visar att hinder för en utökad och kommersiell odling är låg kunskap om hampan och dess egenskaper, dyrt utsäde, brist på lämpliga maskiner och en lagstiftning som ger utrymme för bred tolkning som narkotika och läkemedelskopplade tolkningar. Drivkrafter för ökad hampaodling är bland annat att grödan är mycket intressant och har stor potential att användas som råvara inom ett brett användningsområde. Den har god konkurrens mot ogräs och den är bra för miljön då den kan sanera mark som är förorenad av tungmetaller samt kan ersätta fossila material i tillverkningsindustrin och bomull i textilindustrin. Studien drar genom litteraturstudien slutsatsen att odling och användning av hampa i teorin har goda förutsättningar att bidra till att nå elva av sexton nationella miljömål. Drivkrafter för en ökad odling är en nyfikenhet på grödan, hampans potential att ut ett miljöperspektiv ersätta sämre råvaror och material samt konkurrensförmågan mot ogräs och minskat behov av växtskyddsmedel. Dock framkommer det ett flertal aspekter i intervjustudien som visar att i praktiken finns hinder som påverkar och hämmar en utökad och kommersiell odling av hampa, och därmed även möjligheten att bidra till att nå miljömålen. Lagstiftningen behöver förtydligas både för odlare samt myndigheter för att undvika osäkerhet och tolkningsproblem kring industrihampa kontra droghampa. Kunskapen om odling och användning av hampan behöver öka samt spridas. Större efterfrågan på hampa som råvara behövs. Här ligger ett stort ansvar på Sveriges regering och tillverkningsindustrin att lyfta fram grödan som ett alternativ.

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  • 357.
    Böhm, Annette
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Embedded Systems (CERES).
    Jonsson, Magnus
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Embedded Systems (CERES).
    Handover in IEEE 802.11p-based delay-sensitive vehicle-to-infrastructure communication2009Report (Other academic)
    Abstract [en]

    Based on communication and cooperation between vehicles and roadside infrastructure, Intelligent Transport Systems (ITS) safety applications offer great potential to avoid traffic accidents or at least reduce their impact. As these applications usually are delay-sensitive, the delay introduced by waiting for access to the wireless communication channel should both be reduced and provided with an upper bound. The proposed IEEE 802.11p standard for short to medium range vehicular communication does not offer these guarantees. In previous work, we presented a MAC (Medium Access Control) enhancement supporting delay-sensitive, safety-critical V2I (Vehicle-to-Infrastructure) applications. Since the proposed enhancement requires a deterministic and fast mechanism to associate a vehicle to a roadside unit (RSU) so that it can be integrated into the centralized polling schedule, we now target the handover and connection setup between a vehicle and an RSU. Although the first connection setup with an RSU still underlies the randomness of the original 802.11p MAC method, we provide a deterministic solution to further enhance the handover procedures by introducing a fast, proactive handover mechanism. We show that the overhead of our solution is limited and still allows our MAC protocol to support safety-critical V2I applications in a densely trafficked highway scenario.

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  • 358.
    Böhm, Annette
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Jonsson, Magnus
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Position-based data traffic prioritization in safety-critical, real-time vehicle-to-infrastructure communication2009In: IEEE International Conference on Communications Workshops, 2009. ICC Workshops 2009 / [ed] IEEE, Piscataway, N.J.: IEEE Press, 2009, p. 205-210Conference paper (Refereed)
    Abstract [en]

    Future active-safety applications in vehicular networks rely heavily on the support for real-time inter-vehicle communication. The Medium Access Control (MAC) mechanism proposed for the upcoming IEEE 802.11p standard intended for Intelligent Transport Systems (ITS) applications does not offer deterministic real-time support, i.e., the channel access delay is not upper bounded. We therefore propose a vehicle-to-infrastructure (V2I) communication solution extending IEEE 802.11p, by introducing a collision-free MAC phase with an enhanced prioritization mechanism based on vehicle positions and the overall road traffic density. A road side unit using a polling mechanism is then able to provide real-time support such that it can guarantee collision-free channel access within its transmission range. Part of the bandwidth remains unchanged such that best-effort services like ongoing vehicle-to-vehicle (V2V) applications may continue. Our solution guarantees that all communication deadlines of the V2I applications are met, while minimizing the required length of the collision-free phase. This in turn maximizes the amount of bandwidth available for best-effort services and ongoing V2V applications. The position-based prioritization mechanism further improves the throughput of both real-time and best-effort data traffic by focusing the communication resources to the most hazardous areas. The concept is evaluated analytically based on a realistic task set from a V2I merge assistance scenario.

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  • 359.
    Böhm, Annette
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Jonsson, Magnus
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Kunert, Kristina
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    A fibre-optic AWG-based real-time network for high-performance embedded computing2004Conference paper (Refereed)
    Abstract [en]

    In this paper, an architecture and a Medium Access Control (MAC) protocol for a multiwavelength optical communication network, applicable in short range communication systems like System Area Networks (SANs), are proposed. The main focus lies on guaranteed support for hard and soft real-time traffic. The network is based upon a single-hop star topology with an Arrayed Waveguide Grating (AWG) at its center. Traffic scheduling is centralized in one node (residing together with the AWG in a hub), which communicates through a physical control channel. The AWG’s property of spatial wavelength reuse and the combination of fixedtuned and tunable transceivers in the nodes enable simultaneous control and data transmission. A case study with defined real-time communication requirements in the field of Radar Signal Processing (RSP) was carried out and indicates that the proposed system is very suitable for this kind of application.

  • 360.
    Böhm, Annette
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Jonsson, Magnus
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Embedded Systems (CERES).
    Kunert, Kristina
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Hoang, Hoai
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    A Fibre-Optic AWG-Based Real-Time Network and Its Applicability to High-Performance Embedded Computing2005In: 19th International Parallel and Distributed Processing Symposium: proceedings, Piscataway, N.J.: IEEE Press, 2005, p. 133b-133b, article id 1419972Conference paper (Refereed)
    Abstract [en]

    In this paper, an architecture and a Medium Access Control (MAC) protocol for a multi-wavelength optical communication network, applicable in short range communication systems like System Area Networks (SANs), are proposed. The main focus lies on guaranteed support for hard and soft real-time traffic. The network is based upon a single-hop star topology with an Arrayed Waveguide Grating (AWG) at its center. Traffic scheduling is centralized in one node (residing together with the AWG in a hub), which communicates through a physical control channel. The AWG's property of spatial wavelength reuse and the combination of fixed-tuned and tunable transceivers in the nodes enable simultaneous control and data transmission. A case study with defined real-time communication requirements in the field of Radar Signal Processing (RSP) was carried out and indicates that the proposed system is very suitable for this kind of application.

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    FULLTEXT01
  • 361.
    Böhm, Annette
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Kunert, Kristina
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Data age based MAC scheme for fast and reliable communication within and between platoons of vehicles2016In: International Conference on Wireless and Mobile Computing, Networking and Communications, Piscataway: IEEE, 2016Conference paper (Refereed)
    Abstract [en]

    Heavy vehicles driving as platoon with highly reduced inter-vehicle gaps has shown considerable fuel saving potential, but put high timing and reliability requirements on the underlying control data exchange. The recently standardized IEEE 802.11p protocol suite for Vehicular Ad-Hoc Networks (VANETs) and its message types do neither support the demands of a platooning application nor take advantage of its properties. We therefore propose a framework for centralized channel access with retransmission capabilities for safety critical control data exchange based on the data age of earlier received messages, DA-RE (Data Age based REtransmission scheme). A simulation comparison to the 802.11p random access Medium Access Control (MAC) protocol shows that the intelligent assignment of retransmission opportunities considerably improves the reliability of platooning control data. We also propose a power control based scheme for early platoon detection allowing several platoons to temporarily share a channel and show that the safe and reliable operation of their vehicles is not compromised. © 2016 IEEE.

  • 362.
    Cajander, Amanda
    et al.
    Halmstad University, School of Education, Humanities and Social Science.
    Glamocic, Sanela
    Halmstad University, School of Education, Humanities and Social Science.
    En litteraturstudie av elevers lärande inom geometri i grundskolan med stöd av digitala verktyg2019Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Based on our experiences, literature and research literature, some teachers experience that certain parts of the subject geometry are difficult to teach about. They also experience that the teaching aids are not sufficient enough for developing their teaching. The research we mentioned is that some students do not get enough teaching to be able to conduct mathematical conversations about geometric objects, to relate the objects to each other and insert them into different contexts. Some students also have difficulties in problematizing and constructing geometric objects. With dynamic geometry and the use of digital tools, students can have more time to develop their understanding of geometric objects being constructed. The aim of this literature study is to compile how research describes teaching the subject geometry with the support of digital tools, and more specifically, to answer the question: How can teaching in geometry, according to research, be developed by using digital tools? To answer the question and achieve the aim of the study, we have systematically presented, analyzed and compiled scientific studies on the use of digital tools in the teaching of geometry. Our results show that digital tools enable exploratory working methods, social interaction and increase some students' motivation and commitment, and that some students van Hiele-level in geometric thinking increase while using digital tools. Finally, we discuss didactic implications such as that digital tools contribute to an exploratory approach and increase students' involvement and motivation. Another implication is that all schools do not have access to digital tools and that technical problems can arise when using these, which can lead to a reduction of teaching time. As a proposal for further research, we see an opportunity to look at how the creation and display of video clips affect pupils' learning in geometry.

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  • 363.
    Calikus, Ece
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Self-Monitoring using Joint Human-Machine Learning: Algorithms and Applications2020Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The ability to diagnose deviations and predict faults effectively is an important task in various industrial domains for minimizing costs and productivity loss and also conserving environmental resources. However, the majority of the efforts for diagnostics are still carried out by human experts in a time-consuming and expensive manner. Automated data-driven solutions are needed for continuous monitoring of complex systems over time. On the other hand, domain expertise plays a significant role in developing, evaluating, and improving diagnostics and monitoring functions. Therefore, automatically derived solutions must be able to interact with domain experts by taking advantage of available a priori knowledge and by incorporating their feedback into the learning process.

    This thesis and appended papers tackle the problem of generating a real-world self-monitoring system for continuous monitoring of machines and operations by developing algorithms that can learn data streams and their relations over time and detect anomalies using joint-human machine learning. Throughout this thesis, we have described a number of different approaches, each designed for the needs of a self-monitoring system, and have composed these methods into a coherent framework. More specifically, we presented a two-layer meta-framework, in which the first layer was concerned with learning appropriate data representations and detectinganomalies in an unsupervised fashion, and the second layer aimed at interactively exploiting available expert knowledge in a joint human-machine learning fashion.

    Furthermore, district heating has been the focus of this thesis as the application domain with the goal of automatically detecting faults and anomalies by comparing heat demands among different groups of customers. We applied and enriched different methods on this domain, which then contributed to the development and improvement of the meta-framework. The contributions that result from the studies included in this work can be summarized into four categories: (1) exploring different data representations that are suitable for the self-monitoring task based on data characteristics and domain knowledge, (2) discovering patterns and groups in data that describe normal behavior of the monitored system/systems, (3) implementing methods to successfully discriminate anomalies from the normal behavior, and (4) incorporating domain knowledge and expert feedback into self-monitoring.

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  • 364.
    Calikus, Ece
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Pinheiro Sant'Anna, Anita
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Dikmen, Onur
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    No Free Lunch But A Cheaper Supper: A General Framework for Streaming Anomaly Detection2020In: Expert systems with applications, ISSN 0957-4174, E-ISSN 1873-6793Article in journal (Refereed)
    Abstract [en]

    In recent years, there has been increased research interest in detecting anomalies in temporal streaming data. A variety of algorithms have been developed in the data mining community, which can be divided into two categories (i.e., general and ad hoc). In most cases, general approaches assume the one-size-fits-all solution model where a single anomaly detector can detect all anomalies in any domain.  To date, there exists no single general method that has been shown to outperform the others across different anomaly types, use cases and datasets. On the other hand, ad hoc approaches that are designed for a specific application lack flexibility. Adapting an existing algorithm is not straightforward if the specific constraints or requirements for the existing task change. In this paper, we propose SAFARI, a general framework formulated by abstracting and unifying the fundamental tasks in streaming anomaly detection, which provides a flexible and extensible anomaly detection procedure. SAFARI helps to facilitate more elaborate algorithm comparisons by allowing us to isolate the effects of shared and unique characteristics of different algorithms on detection performance. Using SAFARI, we have implemented various anomaly detectors and identified a research gap that motivates us to propose a novel learning strategy in this work. We conducted an extensive evaluation study of 20 detectors that are composed using SAFARI and compared their performances using real-world benchmark datasets with different properties. The results indicate that there is no single superior detector that works well for every case, proving our hypothesis that "there is no free lunch" in the streaming anomaly detection world. Finally, we discuss the benefits and drawbacks of each method in-depth and draw a set of conclusions to guide future users of SAFARI.

  • 365.
    Caltais, Georgiana
    et al.
    University of Konstanz, Konstanz, Germany.
    Leue, Stefan
    University of Konstanz, Konstanz, Germany.
    Mousavi, Mohammad Reza
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    (De-)Composing Causality in Labeled Transition Systems2016In: 1st Workshop on Causal Reasoning for Embedded and safety-critical Systems Technologies (CREST’16) / [ed] Gregor Gössler & Oleg Sokolsky, Open Publishing Association , 2016, Vol. 224, p. 10-24Conference paper (Refereed)
    Abstract [en]

    In this paper we introduce a notion of counterfactual causality in the Halpern and Pearl sense that is compositional with respect to the interleaving of transition systems. The formal framework for reasoning on what caused the violation of a safety property is established in the context of labeled transition systems and Hennessy Milner logic. The compositionality results are devised for non-communicating systems.

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  • 366.
    Calvo, Rodrigo
    et al.
    Department of Computer Science and Statistics, University of São Paulo, Sao Carlos - SP, Brazil.
    Figueiredo, Maurício Fernandes
    Department of Computer Science, State University of Maringa, Maringa - PR, Brazil.
    Antonelo, Eric Aislan
    Halmstad University, School of Information Technology.
    Evolutionary fuzzy system for architecture control in a constructive neural network2005In: Proceedings 2005 IEEE International Symposium on Computational Intelligence in Robotics and Automation: CIRA 2005. June 27-30, 2005. Espoo, Finland, New York, NY: Institute of Electrical and Electronics Engineers (IEEE), 2005, p. 541-546Conference paper (Refereed)
    Abstract [en]

    This work describes an evolutionary system to control the growth of a constructive neural network for autonomous navigation. A classifier system generates Takagi-Sugeno fuzzy rules and controls the architecture of a constructive neural network. The performance of the mobile robot guides the evolutionary learning mechanism. Experiments show the efficiency of the classifier fuzzy system for analyzing if it is worth inserting a new neuron into the architecture. ©2005 IEEE.

  • 367.
    Cameron, J.
    et al.
    DiLab i Lund AB.
    Jacobson, C.
    AstraZeneca R and D.
    Nilsson, Kenneth
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Rögnvaldsson, Thorsteinn
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    A biometric approach to laboratory rodent identification2007In: Lab animal, ISSN 0093-7355, E-ISSN 1548-4475, Vol. 36, no 3, p. 36-40Article in journal (Refereed)
    Abstract [en]

    Individual identification of laboratory rodents typically involves invasive methods, such as tattoos, ear clips, and implanted transponders. Beyond the ethical dilemmas they may present, these methods may cause pain or distress that confounds research results. The authors describe a prototype device for biometric identification of laboratory rodents that would allow researchers to identify rodents without the complications of other methods. The device, which uses the rodent's ear blood vessel pattern as the identifier, is fast, automatic, noninvasive, and painless.

  • 368.
    Campanini, D.
    et al.
    Department of Physics, Stockholm University, Stockholm, SE-106 91, Sweden.
    Diao, Zhu
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), MPE-lab.
    Rydh, Andreas
    Department of Physics, Stockholm University, Stockholm, SE-106 91, Sweden.
    Raising the superconducting Tc of gallium: In situ characterization of the transformation of α -Ga into β -Ga2018In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 97, no 18, article id 184517Article in journal (Refereed)
    Abstract [en]

    Gallium (Ga) displays several metastable phases. Superconductivity is strongly enhanced in the metastable β-Ga with a critical temperature Tc=6.04(5)K, while stable α-Ga has a much lower Tc<1.2K. Here we use a membrane-based nanocalorimeter to initiate the transition from α-Ga to β-Ga on demand, as well as study the specific heat of the two phases on one and the same sample. The in situ transformation is initiated by bringing the temperature to about 10K above the melting temperature of α-Ga. After such treatment, the liquid supercools down to 232K, where β-Ga solidifies. We find that β-Ga is a strong-coupling type-I superconductor with Δ(0)/kBTc=2.00(5) and a Sommerfeld coefficient γn=1.53(4)mJ/molK2, 2.55 times higher than that in the α phase. The results allow a detailed comparison of fundamental thermodynamic properties between the two phases. © 2018 American Physical Society.

  • 369.
    Carbonnier, Anders
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Martinsson, Ninni
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Examining muscle activation for Hang Clean and three different TRX Power Exercises: A validation study2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Resistance training has proven to increase athletic performance, traditionally barbell training and Olympic Lifting have been used for this purpose. Sling training has recently been developed as a complement or substitution to traditional resistance training. Research has shown an increase in sport specific athletic performance and core stability with sling training. TRX Suspension Trainer is a newly developed sling training tool and to date no independent research has been done with the TRX. Purpose: To examine and compare muscle activation using TRX and the Olympic Lifting movement Hang Clean. Methods: 32 senior high school male soccer players participated in the study. Surface electromyographic (sEMG) data were collected on mm.erector spinae (back), m.gluteus maximus (glutes), m.vastus lateralis (quadriceps), m.semitendinosus (hamstrings) and m.gastrocnemius caput laterale (calf). Surface EMG data was collected when the subjects performed five different exercises, Hang Clean, TRX Squat Jump, TRX Front Squat and TRX Power Pull. In addition a Squat Jump was used as reference. Results: A similar muscle activation was found between Hang Clean (674 µV), TRX Squat Jump (684 µV) and TRX Front Squat (691 µV). TRX Power Pull showed the highest activation for mm.erector spinae and m.gluteus maximus but the lowest when comparing total muscle activation for all measured muscles. Conclusion: The similar amount of muscular activation for Hang Clean, TRX Squat Jump and TRX Front Squat indicates that the TRX Suspension Trainer can be used as a complement, for experienced athletes, or a substitution, for novice athletes, to traditional strength training. Coaches and athletic trainers should acknowledge the need and the importance of resistance training for athletic performance.

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  • 370.
    Cardol, Pierre
    et al.
    Genetics of Microorganisms, University of Liège, Liège, Belgium.
    Figueroa, Francisco
    Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Córdoba. Campus de Rabanalles, Edif. Severo Ochoa, Córdoba, Spain.
    Remacle, Claire
    Genetics of Microorganisms, University of Liège, Liège, Belgium.
    Franzén, Lars-Gunnar
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Plant Cell Biology: Energy transduction in plant cells.
    González-Halphen, Diego
    Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Colonia Copilco-Universidad, Delegación Coyoacán, México D.F., Mexico.
    Oxidative Phosphorylation: Building blocks and related components2009In: The Chlamydomonas Sourcebook: Organellar and Metabolic Processes, Volume 2, Second Edition / [ed] Elizabeth H. Harris, David B. Stern & George B. Witman, Oxford: Academic Press, 2009, p. 469-502Chapter in book (Other academic)
    Abstract [en]

    This chapter summarizes the knowledge of the oxidative phosphorylation (OXPHOS) constituents of Chlamydomonas and of the components involved in their biogenesis and addresses alternate dehydrogenases and oxidases which are particular to photosynthetic organisms, and several other mitochondrial components related to OXPHOS. Reference to the components of Polytomella sp., a colorless alga closely related to Chlamydomonas is clearly made. The main complexes involved in electron transport seem to share a similar number of subunits, and many of the algal polypeptides have plant homologues. Some differences are apparent, such as the presence of a fragmented COX2 subunit, which seems to be unique to chlorophyte algae. OXPHOS is defined as an electron transfer chain driven by substrate oxidation that is coupled to the synthesis of ATP through an electrochemical transmembrane gradient. The characterization of Arabidopsis mitochondrial components through proteomic approaches has advanced significantly. As a unicellular organism, Chlamydomonas offers the unique opportunity to study organelle-organelle interactions, particularly between mitochondria and chloroplasts. It has become evident that crosstalk between these organelles takes place, mainly through intracellular metabolite pools. © 2009 Elsevier Inc. All rights reserved.

  • 371.
    Carlfjord, Salli
    Halmstad University, School of Business, Engineering and Science.
    Correlation between upper body strength and sprint performance in the four competitive strokes of swimming2015Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    BACKGROUND: There are four different strokes in competitive swimming; butterfly (BU), backstroke (BA), breaststroke (BR) and freestyle (FR), all strokes demanding different skills from the athlete. Numerous studies have examined the relationship between upper body strength and FR swimming performance while the other strokes are scarcely investigated. AIM: The aim of this study was to investigate the strength of the correlation between absolute upper body maximum strength, examined by the latpull, and swimming velocity, evaluated by swim sprint performance time, in the four different strokes in sprint swimming. METHODS: Fifteen elite male swimmers, age 14- 29 years, were included in the study. The study had an experimental design where the subjects performed a swim test including 50 meters of each swimming stroke in an indoor 25-meter pool. A maximum strength test was performed 12-72 hours after the swim test, using the latpull as an upper body strength measure. The Pearson correlation coefficient was used to analyse the strength of the correlation between swimming performance in the four different strokes and absolute upper body maximum strength. RESULTS: The strokes displaying the strongest correlations between swimming performance and maximum strength were FR (r=0.49, p=0.065), BU (r=0.48, p=0.073) and BA (r=0.46, p=0.081). BR presented the weakest correlation (r=0.11, p=0.69). CONCLUSIONS: There is a moderate correlation between upper body maximum strength and FR, BA and BU swimming performance and a weak correlation between upper body maximum strength and BR swimming performance. The transferability to other groups can be questioned since the results were not statistically significant. Further research is emphasized examining a larger number of subjects specialized in a certain stroke to develop the understanding of resistance training’s influence on swimming performance in the four competitive strokes of swimming. 

  • 372.
    Carlsson, Elenore
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Mobarak, Sanna
    Halmstad University, School of Business, Engineering and Science.
    Animaliskt matsvinn från tre olika steg i livsmedelskedjan2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

     One of the 16 environmental goals in Sweden is about reducing climate impact. The purpose of this goal is to stabilize greenhouse gases to a level that still preserves the biodiversity and ensures the food production. Production of animal products like meat, milk or eggs, contribute to a large extent to emissions of greenhouse gases. In today's society there is a lot of unnecessarily food waste of these animal products, which is a subject that we should pay more attention to. The aim of this study is to investigate how the reduction of food waste from animal products could reduce greenhouse gas emissions, by adding the need to produce so many animal products. We determine this by collecting data from different steps in the value chain. Primary producers, supermarkets and private persons were asked about how much of their food waste that comes from meat, dairy products and eggs. The aim is also to collect qualitative data about how conscious producers and consumers are about climate impact from animal products and how actively they work to reduce the food waste and how they handle the waste.   To investigate this subject, questionnaires were designed and distributed to primary producers, supermarkets and private consumers. Private consumers were also given a table to keep notes about their food waste. They estimated their food waste from animal products during four weeks. For the background information a literature search has also been done.   The results from primary producers and supermarkets shows that the food waste from meat products was the most abundant compared to dairy products and eggs. Private persons on the other hand mainly had food waste from animal products consisting of dairy products especially sour milk, yoghurt and milk. Private consumers average waste from meat was 0.36 kg/ four weeks which contributes with a climate impact of 6.5 kg , which will be 77.8 kg of year. This corresponds to a one-way trip by plane from Stockholm Arlanda to Copenhagen Kastrup. These numbers were only from 10 households in Sweden, which could mean an uncertainty of the results, showed that primary producers and supermarkets made efforts to reduce the waste. There is also an awareness about animal products and climate impact in all the three categories but the consciousness can be developed more. With increased knowledge about climate impact food waste can be reduced and the management of the food waste can be improved.

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  • 373.
    Carlstedt, Charlotte
    et al.
    Halmstad University, School of Teacher Education (LUT).
    Spånberg, Elin
    Halmstad University, School of Teacher Education (LUT).
    Hållbar utveckling inom ekologi: Fyra verksamma förskolepedagogers uppfattningar2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Hållbar utveckling inom ekologi, en studie gjord utifrån två kvalitativa gruppintervjuer på två slumpmässigt utvalda förskolor, där syftet är att belysa variationen av de fyra deltagande pedagogernas uppfattningar kring hållbar utveckling inom ekologi. Ett problem är att det enligt forskningen finns en osäkerhet i att undervisa naturvetenskap bland pedagoger. De är frågetecken i vad och hur pedagogerna ska undervisa. Det som studien resulterat i är exempel på vad pedagoger i förskolan har för uppfattningar om vad hållbar utveckling inom ekologi är och hur de ser på sitt arbete i ämnet.

     Eftersom studien fokuserar på pedagogernas uppfattningar är den fenomenografisk, men tar även avstamp i hermeneutiken eftersom den utgår från vår förförståelse och tidigare erfarenhet om problemet med ämnet.

     

    Resultatet av studien visar vad de deltagande pedagogerna har för uppfattningar om vad hållbar utveckling inom ekologi är. Enligt pedagogerna är hållbar utveckling inom ekologi ett prioriterat och viktigt ämne, som barnen ska få ta del av redan i tidig ålder. De handlar om att värna om vår jord och att ge barnen möjligheter att vistas i och uppleva naturen.           

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  • 374.
    Carlzon, Linnéa
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Karlsson, Amanda
    Halmstad University, School of Business, Engineering and Science.
    Extreme weather affects the peregrine falcon’s (Falco peregrinus tundrius) breeding success on South Greenland2017Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    In order to understand the effects of climate change on the peregrine’s future prospects, we investigated the relationship between weather variables (extreme weather) and breeding success parameters for the peregrine in South Greenland.

    We defined two variables for comparison with weather data: young per known territory and nest success, i.e. proportion of known sites producing young, for each monitored year (N = 33). Weather data were obtained from two weather stations in the study area. From the weather data four extreme predictor variables were calculated: extreme low temperature, extreme precipitation, consecutive rainy days and total days with extreme weather. Peregrine breeding success (both parameters) was correlated negatively with number of days with extreme weather; the strongest correlation found was between total days in the season with extreme weather and breeding success. Low temperature and total days with extreme weather during the pre-laying and incubation period were also significantly negatively correlated with breeding success. Thereby, extreme weather is an important factor in explaining the peregrine’s breeding success. However, other factors also influence the breeding success, in the last few years there has been a strong downward trend but not an increase of extreme weather events during the same period.

  • 375.
    Carlzon, Linnéa
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Karlsson, Amanda
    Halmstad University, School of Business, Engineering and Science.
    Falk, Knud
    www.vandrefalk.dk, Stockholm, Sweden.
    Liess, Antonia
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Møller, Søren
    Roskilde University Library, Roskilde, Denmark.
    Extreme weather affects Peregrine Falcon (Falco peregrinus tundrius) breeding success in South Greenland2018In: Ornis Hungarica, ISSN 1215-1610, Vol. 26, no 2, p. 38-50Article in journal (Refereed)
    Abstract [en]

    In order to better understand the potential effects of climate change on the Peregrine Falcon, we investigated the relationship between extreme weather events and Peregrines’ breeding success in South Greenland. We defined three variables – number of days with extremely low temperatures, extreme precipitation, consecutive rainy days – and an additive variable, total days with extreme weather, and tested their relationship with Peregrines’ breeding success (measured as young per site and nest success) over a 33 year study period. Breeding success was negatively influenced by the number of days with extreme weather and extremely low temperature. The strongest relationship found was total days with extreme weather in the entire breeding season, which explained 22% and 27% of the variation in nest success and young per site, respectively. The number of days with extreme weather in our study related to fluctuations in the North Atlantic Oscillation (NAO). Thus, with a strengthening of the NAO, linked to climate change, more extreme weather may occur in the Arctic and induce increased variation in Peregrines’ breeding success. Our data did not allow us to pinpoint when in the breeding cycle inclement weather was particularly harmful, and we recommend finer-scale research (e.g. automated nest cameras) to better monitor the species-specific effects of rapidly changing climate.

  • 376.
    Carpatorea, Iulian
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Methods to quantify and qualify truck driver performance2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Fuel consumption is a major economical component of vehicles, particularly for heavy-duty vehicles. It is dependent on many factors, such as driver and environment, and control over some factors is present, e.g. route, and we can try to optimize others, e.g. driver. The driver is responsible for around 30% of the operational cost for the fleet operator and is therefore important to have efficient drivers as they also inuence fuel consumption which is another major cost, amounting to around 40% of vehicle operation. The difference between good and bad drivers can be substantial, depending on the environment, experience and other factors.

    In this thesis, two methods are proposed that aim at quantifying and qualifying driver performance of heavy duty vehicles with respect to fuel consumption. The first method, Fuel under Predefined Conditions (FPC), makes use of domain knowledge in order to incorporate effect of factors which are not measured. Due to the complexity of the vehicles, many factors cannot be quantified precisely or even measured, e.g. wind speed and direction, tire pressure. For FPC to be feasible, several assumptions need to be made regarding unmeasured variables. The effect of said unmeasured variables has to be quantified, which is done by defining specific conditions that enable their estimation. Having calculated the effect of unmeasured variables, the contribution of measured variables can be estimated. All the steps are required to be able to calculate the influence of the driver. The second method, Accelerator Pedal Position - Engine Speed (APPES) seeks to qualify driver performance irrespective of the external factors by analyzing driver intention. APPES is a 2D histogram build from the two mentioned signals. Driver performance is expressed, in this case, using features calculated from APPES.

    The focus of first method is to quantify fuel consumption, giving us the possibility to estimate driver performance. The second method is more skewed towards qualitative analysis allowing a better understanding of driver decisions and how they affect fuel consumption. Both methods have the ability to give transferable knowledge that can be used to improve driver's performance or automatic driving systems.

    Throughout the thesis and attached articles we show that both methods are able to operate within the specified conditions and achieve the set goal.

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  • 377.
    Carpatorea, Iulian Nicolae
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    A graphical traffic scenario editing and evaluation software2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    An interactive tool is developed for the purpose of rapid exploration ofdiverse traffic scenario. The focus is on rapidity of design and evaluation rather thenon physical realism. Core aspects are the ability to define the essential elements fora traffic scenario such as a road network and vehicles. Cubic Bezier curves are usedto design the roads and vehicle trajectory. A prediction algorithm is used to visualizevehicle future poses and collisions and thus provide means for evaluation of saidscenario. Such a program was created using C++ with the help of Qt libraries.

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  • 378.
    Carpatorea, Iulian
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Rögnvaldsson, Thorsteinn
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Elmer, Marcus
    Volvo Group Trucks Technology, Advanced Technology & Research, Göteborg, Sweden.
    APPES Maps as Tools for Quantifying Performance of Truck Drivers2014In: Proceedings of the 2014 International Conference on Data Mining, DMIN'14 / [ed] Robert Stahlbock & Gary M. Weiss, USA: CSREA Press, 2014, p. 10-16Conference paper (Refereed)
    Abstract [en]

    Understanding and quantifying drivers’ influence on fuel consumption is an important and challenging problem. A number of commonly used approaches are based on collection of Accelerator Pedal Position - Engine Speed (APPES) maps. Up until now, however, most publicly available results are based on limited amounts of data collected in experiments performed under well-controlled conditions. Before APPES maps can be considered a reliable solution, there is a need to evaluate the usefulness of those models on a larger and more representative data.

    In this paper we present analysis of APPES maps that were collected, under actual operating conditions, on more than 1200 trips performed by a fleet of 5 Volvo trucks owned by a commercial transporter in Europe. We use Gaussian Mixture Models to identify areas of those maps that correspond to different types of driver behaviour, and investigate how the parameters of those models relate to variables of interest such as vehicle weight or fuel consumption.

  • 379.
    Carpatorea, Iulian
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Rögnvaldsson, Thorsteinn
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Elmer, Marcus
    Volvo Group Trucks Technology, Advanced Technology & Research, Göteborg, Sweden.
    Towards Data Driven Method for Quantifying Performance of Truck Drivers2014In: The SAIS Workshop 2014 Proceedings, Swedish Artificial Intelligence Society (SAIS) , 2014, p. 133-142Conference paper (Refereed)
    Abstract [en]

    Understanding factors that influence fuel consumption is a very important task both for the OEMs in the automotive industry and for their customers. There is a lot of knowledge already available concerning this topic, but it is poorly organized and often more anecdotal than rigorously verified. Nowadays, however, rich datasets from actual vehicle usage are available and a data-mining approach can be used to not only validate earlier hypotheses, but also to discover unexpected influencing factors.

    In this paper we particularly focus on analyzing how behavior of drivers affects fuel consumption. To this end we introduce a concept of “Base Value”, a number that incorporates many constant, unmeasured factors. We show our initial results on how it allows us to categorize driver’s performance more accurately than previously used methods. We present a detailed analysis of 32 trips by Volvo trucks that we have selected from a larger database. Those trips have a large overlap in the route traveled, of over 100 km, and at the same time exhibit different driver and fuel consumption characteristics.

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  • 380.
    Carpatorea, Iulian
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Nowaczyk, Sławomir
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Rögnvaldsson, Thorsteinn
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Lodin, Johan
    Volvo Group Trucks Technology, Göteborg, Sweden.
    Features extracted from APPES to enable the categorization of heavy-duty vehicle drivers2017In: 2017 Intelligent Systems Conference (IntelliSys), 2017, p. 476-481Conference paper (Refereed)
    Abstract [en]

    Improving the performance of systems is a goal pursued in all areas and vehicles are no exception. In places like Europe, where the majority of goods are transported over land, it is imperative for fleet operators to have the best efficiency, which results in efforts to improve all aspects of truck operations. We focus on drivers and their performance with respect to fuel consumption. Some of relevant factors are not accounted for inavailable naturalistic data, since it is not feasible to measure them. An alternative is to set up experiments to investigate driver performance but these are expensive and the results are not always conclusive. For example, drivers are usually aware of the experiment’s parameters and adapt their behavior.

    This paper proposes a method that addresses some of the challenges related to categorizing driver performance with respect to fuel consumption in a naturalistic environment. We use expert knowledge to transform the data and explore the resulting structure in a new space. We also show that the regions found in APPES provide useful information related to fuel consumption. The connection between APPES patterns and fuel consumption can be used to, for example, cluster drivers in groups that correspond to high or low performance. © 2017 IEEE

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  • 381.
    Carpatorea, Iulian
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Slawomir, Nowaczyk
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Rögnvaldsson, Thorsteinn
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Elmer, Marcus
    Volvo Group Trucks Technology, Göteborg, Sweden.
    Lodin, Johan
    Volvo Group Trucks Technology, Göteborg, Sweden.
    Learning of Aggregate Features for Comparing Drivers Based on Naturalistic Data2016In: Proceedings: 2016 15th IEEE International Conference on Machine Learning and Applications (ICMLA) / [ed] Lisa O’Conner, Los Alamitos, CA: IEEE Computer Society, 2016, p. 1067-1072Conference paper (Refereed)
    Abstract [en]

    Fuel used by heavy duty trucks is a major cost for logistics companies, and therefore improvements in this area are highly desired. Many of the factors that influence fuel consumption, such as the road type, vehicle configuration or external environment, are difficult to influence. One of the most under-explored ways to lower the costs is training and incentivizing drivers. However, today it is difficult to measure driver performance in a comprehensive way outside of controlled, experimental setting.

    This paper proposes a machine learning methodology for quantifying and qualifying driver performance, with respect to fuel consumption, that is suitable for naturalistic driving situations. The approach is a knowledge-based feature extraction technique, constructing a normalizing fuel consumption value denoted Fuel under Predefined Conditions (FPC), which captures the effect of factors that are relevant but are not measured directly.

    The FPC, together with information available from truck sensors, is then compared against the actual fuel used on a given road segment, quantifying the effects associated with driver behavior or other variables of interest. We show that raw fuel consumption is a biased measure of driver performance, being heavily influenced by other factors such as high load or adversary weather conditions, and that using FPC leads to more accurate results. In this paper we also show evaluation the proposed method using large-scale, real-world, naturalistic database of heavy-duty vehicle operation.

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  • 382.
    Castellani, Ilaria
    et al.
    INRIA Sophia Antipolis Méditerranée, Valbonne, France.
    Mousavi, Mohammad Reza
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Preface: Special issue on Trends in Concurrency Theory (selected invited contributions from the workshops TRENDS 2014 and 2015)2017In: The Journal of logical and algebraic methods in programming, ISSN 2352-2208, E-ISSN 2352-2216, Vol. 87, p. 93-93Article in journal (Other academic)
  • 383.
    Castellani, Ilaria
    et al.
    INRIA Sophia Antipolis Mediterranee, Biot, France.
    Mousavi, Mohammad Reza
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Special issue on Trends in Concurrency Theory (selected invited contributions from the workshops TRENDS 2014 and 2015) Preface2017In: The Journal of logical and algebraic methods in programming, ISSN 2352-2208, E-ISSN 2352-2216, Vol. 87, p. 93-93Article in journal (Other academic)
  • 384.
    Castellano Jorge, Aurora
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science.
    Species richness in riparian vegetation, a pilot study in Halmstad2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The riparian forests are hotspots of biodiversity and serve important roles in maintainingthe water quality. The study and understanding of this ecosystem is basic to know how theriparian zones respond to the threat and the changes produced by the urbanization. Theobjective of this pilot study was to know the species richness and check the status of theriparian vegetation along two different rivers in Halmstad, Nissan and Fylleån. The studywas focus on the status of trees at both rivers to see if the proximity of the city has anyimpact on the biodiversity. In total 9 different species were found, nevertheless only 3 ofthese species were founded on both localizations: Quercus robur, Betula pendula and Pinussylvestris. The Shannon Index showed a higher biodiversity on Nissan riparian zones, whichis the river that present the urban component. The urban area is the one that presentshigher level of biodiversity, tree species and number of individuals but there are notenough to be in a good standard. The result just show that the urban area is in a bettercondition that the natural one. The institutional efforts should be focusing on preserveboth environments with special attention to the natural environment.

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  • 385.
    Ceder, Patric
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Jönsson, Christopher
    Halmstad University, School of Business, Engineering and Science.
    Tillväxttakt hos sydsvenska populationer av trollsländor (Odonata) i ett varmare klimat - en pilotstudie.2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In order to gain better understanding of climate change effects on ecosystems, it is necessary to study the response of different species to predicted climate change. Dragonflies are, due to their ecology, a suitable organism group for conducting such studies. In this pilot study we examined the response in growth- and mortality rate to increased ambient temperatures in an experimental set-up of three temperature levels (20°C, 22°C och 24°C) in larvae of three species from the Aeshnidae family (Aeshna grandis, Aeshna cyanea and Anax imperator).

    A. imperator were, due to insufficient number of collected specimens, excluded in the 22°C temperature regime. The studied species are reproducing in Sweden, but A. grandis and A. cyanea are native, whereas A. imperator is considered newly established since it was first discovered in Sweden in the early 2000’s. Our results show that A. grandis and A. cyanea reacted positively to an increased ambient temperature, in terms of growth rates. However, the response to increased temperatures differed between the two species as A. grandis showed both higher growth- and mortality rate, compared to A. cyanea. Thus, we assume that both species are likely to benefit from the ongoing climate change, but that interactions between them may change. Further studies are required to elucidate how the two species will be affected in presence of newly established species, such as A. imperator. Although, based on our results, the competitiveness of both native species might increase with rising temperatures - which should be considered in future conservation planning.

  • 386.
    Celander, Patrik
    Halmstad University, School of Business, Engineering and Science.
    Strandsandjägaren (Cicindela maritima) i Gullbranna, Tönnersa- och Hökafältets naturreservat– förekomst, hot och förslag till bevarandeåtgärder2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det halländska kustdynlandskapet har utsatts hårt historiskt av framförallt igenväxning, men även andra faktorer som exploatering och friluftsliv har påverkat. Plantering av bergtall och gräs på sanddynerna, för att förhindra sandflykten som drabbade bönderna redan på 1600- talet, gjorde att nästan hela kustdynlandskapet var täckt med vegetation på 1800- talet. Mellan 2012- 2018 restaurerades stora delar av Laholmsbuktens sanddynreservat i samverkan med EU- projektet SandLife, vilkas syfte var att bevara sanddynmiljön, samt gynna dess hotade arter. I sanddynmiljön lever många evertebrater, däribland skalbaggen strandsandjägaren, som i rödlistningsbedömningen 2015 är klassad som Sårbar i Sverige och är föremål för ett nationellt åtgärdsprogram för dess långsiktiga bevarande. Södra Sveriges troligen enda återstående större population återfinns i Gullbranna naturreservat, som tillsammans med Tönnersa- och Hökafältets naturreservat utgör Laholmsbuktens sanddynreservat. Strandsandjägaren lever i Halland längs havsstränder och vid åmynningar, där dess larver gräver tunnlar i lätt fuktig hårt packad fin sand. Tillbakagången av strandsandjägaren i detta habitat tros överensstämma med tillbakagången av det forna dynamiska kustdynlandskapet.

    Detta arbete har gått ut på att inventera larver av strandsandjägare i Laholmsbuktens sanddynreservat, att utvärdera om arten gynnats av de storskaliga sanddynrestaureringarna i samband med SandLifeprojektet 2012-2018, samt urskilja hot och förslag till konkreta bevarandeåtgärder. Jag fann att populationen har ökat betydligt de senaste 15 åren, dock inte till följd av riktade åtgärder utan troligen tack vare den nybildning av habitat som stormen Gudrun åstadkom 2005, samt att en viss spridning av populationen kan ses. Åtgärdsprogrammets långsiktiga mål fram till 2025 är dock inte uppnått än, men en positiv trend syns och möjligheterna finns i Halland att närma sig målet ytterligare. Restaureringarna inom SandLife verkar inte gynnat strandsandjägarpopulationen, då inga nyrestaurerade områden koloniserats, vilket indikerar att riktade bevarandeåtgärder krävs. En stor och förmodligen mycket underskattad störning i området är trampslitage, så åtgärder behöver vidtas genom att t.ex. sätta upp informationsskyltar och göra vissa lämpliga områden där larver hittats svårtillgängliga. Hela 97% av larvpopulationen, som räknades till 3287 larver, återfanns i augusti på näset i Gullbranna naturrservat, på en bara 6 m bred och 435 m lång yta, av habitattypen sandrevlar/åmynningar. I Tönnersa- och Hökafältets naturreservat fann jag bara enstaka larver längs habittypen havsstrand, men dock är det första gången som strandsandjägarlarver hittats i de områdena. Näst största lokalen med strandsandjägare hittades på norra stranden av Gullbrannas naturreservat, med 44 larver räknade i augusti. Resultatet indikerar att havsstränderna är ett sekundärt val för strandsandjägaren i området, och att de inre sanddynerna/sänkorna i nuläget inte verkar erbjuda lämpligt habitat överhuvudtaget, då inga larver återfanns i den habitattypen. Sandrevlar/mynningar är alltså det mest gynnsamma habitatet i området, men då inga larver hittades vid den andra ån Lagan så indikerar det att fler faktorer spelar in, inte minst frånvaro av alltför kraftigt trampslitage. Orsaken till att Genevadsåns mynning hyser nästan hela populationen är troligen att där finns ännu mycket bra habitat, strandsandjägarens troligen små hemområden med låg spridningstendens vid goda förutsättningar och få störningar. Resterande områden har mindre bra habitat, låg spridning till dessa områden, samt mer störningar. Med riktade åtgärder finns det dock potential för flera metapopulationer i de andra områdena, vilket kan leda till en livskraftigare population av strandsandjägaren i Halland.

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  • 387.
    Celik, Ali
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Flygare, Andreas
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Digital mobbning - en explorativ fallstudie med särskilt fokus på utredning2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Internet Infrastructure Foundation has reported that the use of Internet is widespread and places Sweden among the best countries in the world. In 2010, 84 percent of the Swedish population aged 16 and above had access to the Internet at home, and 97 percent of those users had broadband. The most frequent Internet users were in the age group 16-24 years old where 92 percent stated they use the Internet on a daily basis.The spread of the Internet is essentially positive and contributes to the public debate on problems of modern society. This simultaneously leads to a series of new problems that society has to deal with. One of these new problems is harassment and bullying that has reached entirely new dimensions by the use of Internet. Harassment over the Internet has a distribution that is difficult for the victim to handle and respond to. When harassment crosses the border for what is considered a crime according to the penal code, the police face new challenges to handle.The goal of this bachelor's thesis has been to use an exploratory case study to illustrate how the legal system responds to this new form of harassment, including the considerations to start a police investigation, the procedures of the investigation and the court’s ruling. We start from a case of harassment that the court classified as aggravated defamation. The perpetrators are a number of young men aged fifteen to nineteen years old. The young men have made films about girls containing highly offensive content with sexual innuendo and then spread the films through the chat network MSN and even on the video website YouTube. According to the investigation forty girls have been affected. We have reviewed the investigation protocol, the court records and conducted interviews with police investigators in order to illustrate the phenomenon of harassment and bully behavior on the Internet. We also discuss how society measures could be improved.

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  • 388.
    Chalangar, Ebrahim
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS). Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS). Linköping University, Linköping, Sweden.
    Graphene-based nanocomposites for electronics and photocatalysis2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The development of future electronics depends on the availability of suitable functional materials. Printed electronics, for example, relies on access to highly conductive, inexpensive and printable materials, while strong light absorption and low carrier recombination rates are demanded in photocatalysis industry. Despite all efforts to develop new materials, it still remains a challenge to have all the desirable aspects in a single material. One possible route towards novel functional materials, with improved and unprecedented physical properties, is to form composites of different selected materials.

    In this work, we report on hydrothermal growth and characterization of graphene/zinc oxide (GR/ZnO) nanocomposites, suited for electronics and photocatalysis application. For conductive purposes, highly Al-doped ZnO nanorods grown on graphene nanoplates (GNPs) prevent the GNPs from agglomerating and promote conductive paths between the GNPs. The effect of the ZnO nanorod morphology and GR dispersity on the nanocomposite conductivity and GR/ZnO nanorod bonding strength were investigated by conductivity measurements and optical spectroscopy. The inspected samples show that growth in high pH solutions promotes a better graphene dispersity, higher doping and enhanced bonding between the GNPs and the ZnO nanorods. Growth in low pH solutions yield samples characterized by a higher conductivity and a reduced number of surface defects.

    In addition, different GR/ZnO nanocomposites, decorated with plasmonic silver iodide (AgI) nanoparticles, were synthesized and analyzed for solar-driven photocatalysis. The addition of Ag/AgI generates a strong surface plasmon resonance effect involving metallic Ag0, which redshifts the optical absorption maximum into the visible light region enhancing the photocatalytic performance under solar irradiation. A wide range of characterization techniques including, electron microscopy, photoelectron spectroscopy and x-ray diffraction confirm a successful formation of photocatalysts.

    Our findings show that the novel proposed GR-based nanocomposites can lead to further development of efficient photocatalyst materials with applications in removal of organic pollutants, or for fabrication of large volumes of inexpensive porous conjugated GR-semiconductor composites.

  • 389.
    Chamberlain, Richard
    Halmstad University, School of Business, Engineering and Science.
    Validating Citizen Science data for use in the design and management of constructed wetlands: a case study of Tufted Duck and Eurasian Teal.2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Citizen science offers a potentially powerful tool for the environmental scientist to access large data sets over increasingly greater time scales. Given the ease of which information can be reported or shared online and the increase in community interest there is an overwhelming amount of data available. But two major questions remain; is the data reliable and how is it best used? This study addresses the first question by testing the ability of such data from Artportalen, Sweden’s Species Gateway for reporting observations of birds (and other flora and fauna), to reflect patterns in the presence and absence of breeding records of Tufted Duck (Aythya fuligula) and Eurasian Teal (Annas crecca). This was done by undertaking wetland assessments in a set of constructed wetland sites from Artportalen in Halland, Southern Sweden, with breeding records of the target species. A literature review was also undertaken to explore the existing ecological knowledge of breeding habitat requirements for each species. Physical and biological characteristics from the wetlands visited were then qualitatively compared to the existing ecological knowledge for each species’ preferred breeding habitat. This method resulted in some support for the reliability of this particular Citizen Science data, in that it reflected Tufted Duck’s preference to breed in wetlands closer to the coast, that provided some form of cover or screening around the edges and which had a large proportion of their shoreline bordered by tall emergent vegetation. Conversely, it reflected Eurasian Teal’s preference for inland wetlands that were closer to relatively open natural freshwater bodies, where tall emergent vegetation wasn’t as abundant. How this and other Citizen Science data can be used in the design and management of constructed wetlands for conservation purposes in light of these results is then discussed.

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  • 390.
    Chamberlain, Roger
    et al.
    Computer Science and Engineering, Washington University, Saint Louis, USA.
    Taha, WalidHalmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).Törngren, MartinDepartment of Machine Design, KTH Royal Institute of Technology, Stockholm, Sweden.
    Cyber Physical Systems. Model-Based Design: 8th International Workshop, CyPhy 2018, and 14th International Workshop, WESE 2018, Turin, Italy, October 4–5, 2018, Revised Selected Papers2019Conference proceedings (editor) (Refereed)
    Abstract [en]

    This book constitutes the proceedings of the 8th International Workshop on Design, Modeling, and Evaluation of Cyber Physical Systems, CyPhy 2018 and 14th International Workshop on Embedded and Cyber-Physical Systems Education, WESE 2018, held in conjunction with ESWeek 2018, in Torino, Italy, in October 2018. The 13 full papers presented together  with 1 short paper in this volume were carefully reviewed and selected from 18 submissions. The conference presents a wide range of domains including Modeling, simulation, verification, design, cyber-physical systems, embedded systems, real-time systems, safety, and reliability. © 2019 Springer Nature Switzerland AG. Part of Springer Nature.

  • 391.
    Charlson, Alexandra
    Halmstad University, School of Business and Engineering (SET).
    Reduktion av föroreningar i processvatten från en äggfabrik i Brasilien: Kväve- och fosforrening i anlagda våtmarker.2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A water treatment unit consisting of two aeration basins, two settling tanks, a residence basinand a horizontal subsurface flow wetland were used to treat wastewater from an eggprocessing factory in Brazil. The aim of this paper was to determine the efficiency of thesystem in reducing nitrogen, phosphorus, BOD5 and TSS (among other parameters) andgetting a further understanding on different kinds of constructed treatment wetlands as well astheir nitrogen and phosphorus removal processes. The wastewater from the factory consistedof process water from manufacturing and water used for cleaning, no stormwater or sewagewater entered the system. Tests were taken three times a month from October 2013 ‘til April2014. The mean influent concentrations from wastewater directly from the factory were2,606 mg/L, 46.60 mg/L, 318.3 mg/L and 1,112 mg/L for BOD5, TP, TKN and TSS. Themean results of reduction through the wetlands gave the following results; BOD5 42 ± 351%,TP 66 ± 9.7%, TN 42 ± 13% and TS -11 ± 30%. Compared to other wetland systems treatingsimilar wastewater the reduction of BOD5 and TSS is low. Recommended solutions toincrease the reduction in the wetland are presented in the discussion.

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  • 392.
    Cheema, Ansar Zaman
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Saqib, Imran Ullah
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Collaborating ISPs Supporting Various Real-Time Services2010Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    These days, internet service providers (ISPs) face the challenge about how to increase profitability while hey must ensure a good quality service at the same time and scale up their network. The study involves previous research papers. On the bases of those papers,the comparison is made between different alternatives. The purpose on this study is to find a solution that combines different methods and configurations about how several ISPs could cooperate. Its implementation includes how different ISPs can configure their networks to cooperate on service provision supporting various real-time services.

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  • 393.
    Chen, Lei
    et al.
    Research Institutes of Sweden, RISE Viktoria, Lindholmspiren 3A, Gothenburg, 417 56, Sweden.
    Englund, Cristofer
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research.
    Every Second Counts: Integrating Edge Computing and Service Oriented Architecture for Automatic Emergency Management2018In: Journal of Advanced Transportation, ISSN 0197-6729, E-ISSN 2042-3195, p. 13-, article id 7592926Article in journal (Refereed)
    Abstract [en]

    Emergency management has long been recognized as a social challenge due to the criticality of the response time. In emergency situations such as severe traffic accidents, minimizing the response time, which requires close collaborations between all stakeholders involved and distributed intelligence support, leads to greater survival chance of the injured. However, the current response system is far from efficient, despite the rapid development of information and communication technologies. This paper presents an automated collaboration framework for emergency management that coordinates all stakeholders within the emergency response system and fully automates the rescue process. Applying the concept of multiaccess edge computing architecture, as well as choreography of the service oriented architecture, the system allows seamless coordination between multiple organizations in a distributed way through standard web services. A service choreography is designed to globally model the emergency management process from the time an accident occurs until the rescue is finished. The choreography can be synthesized to generate detailed specification on peer-to-peer interaction logic, and then the specification can be enacted and deployed on cloud infrastructures. © 2018 Lei Chen and Cristofer Englund.

  • 394.
    CHEN, XINYAO
    Halmstad University, School of Business, Engineering and Science.
    Using PCA & Repeated ANOVA to evaluate the In Situ Bioremediation performance of sites contaminated by trichloroethylene2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Currently, one of the most common techniques to remediate contaminated sites of TCE is in situ bioremediation (ISB). In this study, PCA and repeated ANOVA were used to statistically analyze the trends of variables over time to aid in the interpretation of the performance of the in situ bioremediation (ISB) technique. cDCE, Mn2+, chloride and alkalinity have appeared a significant trend over time suggested they have relative stronger indicating power to the performance of ISB. The variables that most effectively describe the bioremediation performance are Fe2+, DOC, Mn2+, methane and alkalinity. Their dramatic changes with time indicate the active functioning of dechlorinating bacteria to remediate the contamination. Three group of indicators can be identified according to their trends over time having a certain consistent character. The first group is methane and ethane, the second group consists of chloride, sulfate and alkalinity and the third group consists of cDCE and tDCE. Definitely, PCA can be an effective tool to analyze the overall trends and transformation pattern of variables over time and at different sampling points within the site. However, the fragmented data set reduce the possibilities for a complete understanding of the remediation process at the site.

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  • 395.
    Chibba, Aron
    et al.
    Halmstad University, School of Business, Engineering and Science, Mechanical Engineering and Industrial Design (MTEK).
    Rundquist, Jonas
    Halmstad University, School of Business, Engineering and Science, Centre for Innovation, Entrepreneurship and Learning Research (CIEL), Centre for Technology, Innovation and Marketing Management (CTIM2).
    Effective Information Flow in the Internal Supply Chain: Results from a snowball method to map information flows2009In: Journal of Information & Knowledge Management, ISSN 0219-6492, E-ISSN 1793-6926, Vol. 8, no 4, p. 331-343Article in journal (Refereed)
    Abstract [en]

    Information sharing is an important factor for effectiveness within the internal supply chain. In this paper we use a methodology for mapping information flows in an internal supply chain, and case studies in two Swedish multinational organizations. Eight retrospective cases were used to map, describe and analyze the information flow that supports the physical material flow from the receipt of an order to point of delivery. Every involved person was interviewed on at least one occasion each. The interviews were conducted to map and describe the information and physical material flow. The aim was to identify factors that could improve and rationalise information flows and generate a better flow within the organization.

    The study shows the importance of an integrated information system, but also clearly indicates the importance of a collaborative culture and an awareness of the human-technology interface. The study also shows that three factors of interface distortions are most frequent in the cases: (1) changes registered in the database trigger no action among the staff, (2) new knowledge to staff is stored only orally and not in the database, and (3) interface between the paper system and the database, and between the old and the new information storage culture.

  • 396.
    Chowdhury, Soumitra
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Co-creation of Innovative Digital Services2012Conference paper (Refereed)
    Abstract [en]

    In the context of digital innovation, this paper discusses co-creation of digital services with the help of translation processes described in the Actor-Network Theory (ANT). While using the translation processes such as problematization, interessement and enrolment, the paper delineates how different stakeholders can be involved in the co-creation of innovative digital services. Thus the paper makes a contribution by presenting the co-creation of digital services in the perspective of translation processes of ANT by showing how different actors can be involved in co-creation of digital services. ‘Establishing trust on digital innovation’ and ‘prioritization during digital innovation’ are identified as influential issues for the involvement of actors during digital innovation. In that way, the paper also makes contribution to the emerging literature on digital innovation.

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  • 397.
    Chowdhury, Soumitra
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Expanding Business from Products to Digital Services: Value Dimensions of Digital Services Enabled by Embedded Technology2014In: Proceedings of the 8th Mediterranean Conference on Information Systems / [ed] Mola, L., Carugati, A., Kokkinaki, A., Pouloudi, N., 2014, p. Paper 12-Conference paper (Refereed)
    Abstract [en]

    Manufacturing firms are now embedding digital technology into products with an aim to offer digital services to their customers. Digital services create opportunities for firms to add new value dimensions to their businesses as firms now can expand their businesses from tangible products to digital services. Existing research explains three value dimensions. ‘Value-in-exchange’ is traditionally followed by manufacturing firms where they determine monetary value for their products and exchange the value with customers. Recent research argues that ‘value-in-exchange’ is not customer centric and therefore to gain customer value, ‘value-in-use’ and ‘value-in-cocreation’ are necessary. With growing utilization of embedded digital technology in products, new digital services are rendered and new value dimensions are emanating. Existing research informs little about the value dimensions of digital services that result from the combination of digital technology and tangible products. Therefore, in this research, we seek answer to the question, ‘What are the value dimensions of digital services that are enabled by embedded digital technology in tangible products?’ A qualitative study has been conducted to investigate Remote Diagnostics Services (RDS) for vehicles. Along with the three known value dimensions, that is, value-in-exchange, value-in-use and value-incocreation, this research contributes to knowledge by showing two new value dimensions: ‘value-in-connectivity’ and ‘value-in-architecture’.

  • 398.
    Chowdhury, Soumitra
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab). Department of Applied Information Technology, University of Gothenburg, Gothenburg, Sweden.
    Service Logic in Digitalized Product Platforms: A Study of Digital Service Innovation in the Vehicle Industry2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The digitalization of products has become an important driver for service innovation in manufacturing firms. The embedding of digital technology in previously non-digital products creates digitalized product platforms that enable digital service innovation. Digital service innovation offers new business opportunities for manufacturing industries, as well as challenges established premises for value creation.  While digital service innovation can be found in many manufacturing industries, this thesis studies service logic in digitalized product platforms in the vehicle industry.

    Existing Information Systems (IS) literature presents challenges in digital service innovation relating to value, architecture, and generativity. The design of the architecture of digitalized product platforms requires the identification and combination of digital and non-digital assets. Understanding the architectural aspects is useful in digital service innovation. Moreover, with growing instances of generative digital technologies, it is challenging to develop strategies to leverage generativity for service design in digitalized product platforms. While digital technologies are embedded in products, the role of technology-embeddedness in value creation of digital services is relatively unexplored. Drawing on these challenges, this thesis describes and conceptualizes the underlying premises brought by the architecture and generativity to the value creation of services in digitalized product platforms. The research question addressed in this thesis is: What are the underlying premises for services in digitalized product platforms?

    To address the question, an interpretive qualitative research approach was adopted in a collaborative research project concerning services enabled by digitalization of vehicles. Drawing on digital innovation and service literature, this thesis presents a theoretical perspective on the role of the architecture and generativity of digitalized product platforms for value creation of digital services. This perspective is conceptualized as underlying premises for this specific class of services. The premises frame the service logic in digitalized product platforms and provide a ground for understanding services in digitalized product platforms in relation to value dimensions, architecture and generativity. The premises are based on five concepts: value-in-architecture, value-in-connectivity, fundamental asset for value creation, mutual dependence of modular and layered modular assets, and re-evaluation of value propositions. The proposed premises offer a basis for understanding value creation of this class of services, and guidance for manufacturing firms designing digitalized product platforms.

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  • 399.
    Chowdhury, Soumitra
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Akram, Asif
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Challenges and Opportunities Related to Remote Diagnostics: An IT-based Resource Perspective2013In: International Journal of Information Communication Technologies and Human Development, ISSN 1935-5661, E-ISSN 1935-567X, Vol. 5, no 3, p. 80-96Article in journal (Refereed)
    Abstract [en]

    Remote diagnostics is expanding the business scope of vehicle manufacturers, ranging from products to services. In this paper, we focus on investigating the business challenges and opportunities related to the remote diagnostics of vehicles from an IT-based resource perspective. Remote diagnostics involves technology, human skills and intangibles. IT-based resources consist of physical IT infrastructure, human IT skills and IT-enabled intangibles. In this study, we find that remote diagnostics not only faces challenges in these three categories of IT-based resource, but also creates opportunities. One contribution of this paper is to provide an overview of the challenges and opportunities for business related to the technology. The paper also makes a contribution to information systems by shedding light on the discussion of digital infrastructure. It also highlights the application of IT-based resource perspective to find out the business challenges and opportunities of an emerging technology like remote diagnostics.

  • 400.
    Chowdhury, Soumitra
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    Akram, Asif
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Man and Information technology laboratory (MI-lab).
    E-Maintenance: Opportunities and Challenges2011In: Proceedings of IRIS 2011 / [ed] Leino, Timo, Turku, Finland: Turku Centre for Computer Science , 2011, p. 68-81Conference paper (Refereed)
    Abstract [en]

    E-maintenance offers various opportunities as well as challenges in contemporary business undergoing transformation. This paper provides an overview of opportunities and challenges in different areas related to e-maintenance. Literature review and empirical findings through action oriented research give way to identify and present these opportunities and challenges. One contribution of the paper is, it finds the opportunities and challenges with e-maintenance in different industries which creates a pathway for future direction in further studies regarding e-maintenance. The findings indicate that there is much potential to study these with respect to technology and business.

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    IRIS 2011_ E-maintenance: opportunities and challenges
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