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Fallmyr, Terje; Stabell-Kulø, Tage (Research report; Forskningsrapport, 30-Jun-1997)[+][-]
Abstract: Hand-held mobile computers have the potential to become important communication tools for roaming users. As such, they will also become very personal. They will be used under a wide range of operating conditions, and tight user control will be enforced on issues like power consumption, consistency control, and trust management. Their ability to adapt will be the key to their success. In this paper we outline our notion and use of Quality of Service (QoS) to the design of adaptive software systems for mobile computers. They have been developed in the MobyDick and GDD projects. We do not emphasize on the provision of QoS guarantees. In stead, our notion of QoS is used to convey relevant and timely management information between service users and providers on the correct abstraction level. It structures adaptability management in the hand held machine, and it captures adaptability to changes both stemming from the hosting environment and user commands. As an example of how the architecture works, the importance of adaptivity of security services for personal companions are explained, and we show how our notion of QoS may realize adaptable security services. URI: http://hdl.handle.net/10037/373 File(s) in this item: 1
report.pdf (102.9Kb) -
Hanssen, Øyvind (Doctoral thesis; Doktorgradsavhandling, 07-Feb-2008)[+][-]
Abstract: This thesis addresses negotiation of bindings in QoS aware open systems and in particular how to characterize possible contracts, requirements and capabilities of heterogeneous environments. Our approach is (1) to use trading of policies as the principle for negotiation and (2) the use of declared or rule-based conformance for QoS statements to be used in negotiation and (3) a middleware binding framework supporting negotiable bindings. A policy is an architectural entity which encapsulates a potential QoS contract plus a resource and implementation configuration to enforce the contract. The contract part (profile) consists of an obligation to be matched with requirements and an expectation to be matched with descriptions of the environment. A policy may encapsulate how implementation components and properties of environments are combined to achieve a QoS level. Policy trading is the proposed principle for negotiation. Potential contracts may be orthogonal to interfaces and interface types, and are associated with some trading service. Negotiation is essentially to collect requirements and environment descriptions from participants and match these with policies. We investigate an approach to contract matching based on declared conformance. An important contribution is the development of a declarative expression language for profiles, requirement and environment descriptions used in negotiation at run-time. We propose to define conformance as rule bases. Such rule bases can be compiled to efficient conformance checking code. We propose two composition operators to combine expressions at run-time and develop the foundations of a generic conformance checking algorithm for profile expressions. A prototype binding framework is developed, supporting activation of bindings, pluggable binder and activator components. The framework is extended to support negotiation using policy trading and profile expressions. The approach is validated by examples and proof of concept implementations. A profile model compiler, a policy trader and the binding framework are implemented and applied to example applications. Description: The trial lecture of the thesis defence is available in Munin at http://hdl.handle.net/10037/2840. URI: http://hdl.handle.net/10037/1350 File(s) in this item: 2
appendix.pdf (5.377Mb)thesis.pdf (1.284Mb) -
Khalaila, Ahmad H.; Eliassen, Frank (Research report; Forskningsrapport, May-1997)[+][-]
Abstract: This paper proposes an external sorting algorithm for large data as an alternative to the widely used merge-sort algorithm. The algorithm we present is an application of the widely known quick-sort algorithm to large sequences of data stored externally on a disk device. The problem with the merge-sort algorithm is not its time complexity but the large amount of time it requires to output its first results. This is a serious problem in the context of pipelined processing, since the operations consuming its result will have to wait all that time before they can start their processing, thus limiting the degree of vertical parallelism achievable by pipelined processing Using quick-sort instead of merge-sort for external sorting in pipelined data processing systems results in an optimization in the order of $log N$ (where N is the size of the data sequence to be sorted) for the entire query pipeline where the sorting operation is involved. URI: http://hdl.handle.net/10037/370 File(s) in this item: 1
report.pdf (120.8Kb) -
Klemetsen, Øystein; Jacobsen, Svein Ketil; Birkelund, Yngve (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)[+][-]
Abstract: A new scheme for detection of vesicoureteral reflux (VUR) in children has recently been proposed in the literature. The idea is to warm bladder urine via microwave exposure to at least fever temperatures and observe potential urine reflux from the bladder back to the kidney(s) by medical radiometry. As a preliminary step toward realization of this detection device, we present non-invasive temperature monitoring by use of microwave radiometry in adults to observe temperature dynamics in vivo of a water-filled balloon placed within the oral cavity. The relevance of the approach with respect to detection of VUR in children is motivated by comparing the oral cavity and cheek tissue with axial CT images of young children in the bladder region. Both anatomical locations reveal a triple-layered tissue structure consisting of skin–fat–muscle with a total thickness of about 8–10 mm. In order to mimic variations in urine temperature, the target balloon was flushed with water coupled to a heat exchanger, that was moved between water baths of different temperatures, to induce measurable temperature gradients. The applied radiometer has a center frequency of 3.5 GHz and provides a sensitivity (accuracy) of 0.03 °C for a data acquisition time of 2 s. Three different scenarios were tested and included observation through the cheek tissue with and without an intervening water bolus compartment present. In all cases, radiometric readings observed over a time span of 900 s were shown to be highly correlated (R ~ 0.93) with in situ temperatures obtained by fiberoptic probes. URI: http://hdl.handle.net/10037/5057 File(s) in this item: 1
article.pdf (6.815Mb) -
Holmstad, Øyvind (Master thesis; Mastergradsoppgave, 01-Jun-2011)[+][-]
Abstract: Real-time media rich applications rely on live streams of rich and accurate meta-data describing the video content to provide personal user experiences. Unfortunately, the general amount of video meta-data today is often limited to titles, synopsis and a few keywords. A wildly used approach for extraction of meta-data from video is computer vision. It has been developed a number of different video processing algorithms which can analyse and retrieve useful data from video. However, the computational cost of current computer vision algorithms is considerable. This thesis presents a software architecture that aims to enable real-time annotation of multiple live video streams. The architecture is intended for use within media rich applications where extraction of video semantics in real-time is necessary. Our conjecture was that staging video processing in levels will make room for a more scalable video annotation system. To evaluate our thesis we have developed the prototype runtime Árvdadus. Our experiments show that staged processing can decrease the computation time of meta-data extraction. The evaluation of the architecture suggests that the architecture is applicable in a wide range of domains where extraction of meta-data in real-time is necessary URI: http://hdl.handle.net/10037/3520 File(s) in this item: 1
thesis.pdf (1.715Mb) -
Hansen, Lars Kr; Perlovich, German; Bauer-Brandl, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2006)[+][-]
Abstract: [Erratum to document cited in CA140:010932] URI: http://hdl.handle.net/10037/3174 File(s) in this item: 1
article.pdf (133.1Kb) -
Hansen, Lars Kr; Perlovich, German; Bauer-Brandl, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2007)[+][-]
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Hansen, Lars Kr; Perlovich, German; Bauer-Brandl, Annette D (Journal article; Tidsskriftartikkel; Peer reviewed, 2006)[+][-]
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Jakobsen, Anna-Brith A.; Karlsen, Randi (Research report; Forskningsrapport, 2004)[+][-]
Abstract: Transactional middleware platforms must accommodate an increasingly diverse range of requirements from both applications and the underlying systems. It is clear that applications have characteristics and requirements that vary a lot, and that transactional middleware must be able to support the potential variety in transaction execution requirements. In this paper we describe ReflecTS, a reflective platform for transaction services that will meet the diverse needs of applications. The platform, which is composed of components and component frameworks, supports concurrently running transaction services and exposes the ability to configure and reconfigure the services by adopting the principles of reflection. URI: http://hdl.handle.net/10037/378 File(s) in this item: 1
report.pdf (114.4Kb) -
Skirbekk, Kari (Master thesis; Mastergradsoppgave, 15-Nov-2007)[+][-]
Abstract: Sedimentkjerne NP05-11-21GC fra Kongsfjordrenna vest for Spitsbergen er analysert for å kartlegge utviklingen av paleomiljø de siste ~11 800 år. Analysene er basert på undersøkelser av bentiske foraminiferer og sedimentologiske egenskaper. Kjernen er 5,15 meter lang og 104 prøver er analysert med hensyn på fauna, droppstein og kornfordeling. Sedimentenes fysiske egenskaper er målt ved hjelp av en Multi-Sensor Core Logger, og røntgenbilder er studert. Kjernens kronologi er basert på 10 radiokarbondateringer, og viser at sedimentasjonsraten varierer mellom 27 og 158 cm/tusen år. Sokkelområdet vest for Spitsbergen har vist seg å være sensitiv for endringer i Vest Spitsbergenstrømmens intensitet. Sedimentene i kjerne NP0511-21GC er avsatt i et distalt glasimarint miljø, med en varierende påvirkning fra atlantiske vannmasser og is. Et kaldt og sjøispåvirket miljø i yngre dryas etterfølges av en tostegs bedring av klima i tidlig holosen. Klimabedringen avbrytes av en nedkjøling under den preboreale svingning 11 300 kalenderår før nåtid, hvor kalde lavsaline vannmasser dominerer, og sjøisdekke hindrer avsetning av droppstein over lokaliteten. En gradvis bedring av klima gjennom tidlig holosen kulminerer i et klimatisk optimum om lag 9000 kalenderår før nåtid. En gradvis nedkjøling observeres gjennom midt-holosen overgangsperiode. Høy påvirkning fra isbreer registreres etter 4000 kalenderår i før nåtid, i sen holosen, hvor mye droppstein avsettes på lokaliteten. De generelle trekkene i klimautviklingen er i overensstemmelse med andre proksidata fra Svalbards margin og de Nordiske hav. Innstrømmingen av atlantisk vann i Kongsfjordrenna følger i stor grad endringer i Vest Spitsbergenstrømmen. URI: http://hdl.handle.net/10037/1272 File(s) in this item: 1
thesis.pdf (8.150Mb) -
Deryabin, Alexey (Master thesis; Mastergradsoppgave, 05-Jun-2012)[+][-]
Abstract: This Master thesis investigates the relationship between glacial erosion, glaciotectonically displaced sediment blocks and indications of fluid flow and shallow gas accumulations in buried glacial sediments of the south-western Barents Sea margin. The thesis is based on two three-dimensional (3D) seismic datasets, NH98003 and EL0001, the two-dimensional (2D) seismic survey NH9702 and exploration well 7216/11-1. 3D seismic techniques have allowed mapping and visualizing of buried geomorphological features in great details within the study area. Large semi-circular depressions and fluid migration pathways are imaged, as well as glacigenic sediment blocks and rafts. A glacigenic origin is inferred for the megablocks and rafts indicating high glaciotectonic activity of the former ice streams. Six large-scale depressions are inferred to be sources for the removal of sediment mega-blocks and rafts at one particular stratigraphic level of the Plio-Pleistocene succession. Mapped fluid migration pathways and shallow gas accumulations show evidence of an active fluid migration system, and its spatial relationship with the erosional depressions is documented. Modeling of the gas hydrate stability zone has been performed for glacial and interglacial conditions and its effect on the sediment properties is discussed. A conceptual model is proposed for the formation of the depressions, where brittle glaciotectonic deformation along a weak layer at the base of gas-hydrate cementing sediments is inferred. Subsequent expulsion of gas-rich fluids is assumed to have followed deglaciation which might further have reworked the depressions. URI: http://hdl.handle.net/10037/4216 File(s) in this item: 1
thesis.pdf (19.35Mb) -
Hall, Chris; Xu, X; Manson, Alan; Meek, Chris; Chshyolkova, Tatyana; Drummond, J. R.; Jacobi, Ch.; Riggin, D.; Hibbins, R.E.; Tsutsumi, Masaki; Hocking, W. K.; Ward, W. (Journal article; Tidsskriftartikkel; Peer reviewed, 2009)[+][-]
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Kosch, M.J.; Blixt, Erik Mårten; Semeter, J. (Journal article, 27-Jul-2005)[+][-]
Abstract: Black auroras are recognized as spatially well-defined regions within uniform diffuse aurora where the optical emission is significantly reduced. Although a well studied phenomenon, there is no generally accepted theory for black auroras. One theory suggests that black regions are formed when energetic magnetospheric electrons no longer have access to the loss cone. If this blocking mechanism drifts with the source electron population in the magnetosphere, black auroras in the ionosphere should drift eastward with a velocity that increases with the energy of the precipitating electrons in the surrounding aurora, since the gradient-B curvature drift is energy dependent. It is the purpose of this paper to test this hypothesis. To do so we have used simultaneous measurements by the European Incoherent Scatter (EISCAT) radar and an auroral TV camera at Tromsø, Norway. We have analyzed 8 periods in which a black aurora occurred frequently to determine their relative drift with respect to the ionospheric plasma. The black aurora was found to drift eastward with a velocity of 1.5–4km/s, which is in accordance with earlier observations. However, one case was found where a black patch was moving westward, this being the first report of such behaviour in the literature. In general, the drift was parallel to the ionospheric flow but at a much higher velocity. This suggests that the generating mechanism is not of ionospheric origin. The characteristic energy of the precipitating electron population was estimated through inversion of E-region plasma density profiles. We show that the drift speed of the black patches increased with the energy of the precipitating electrons in a way consistent with the gradient-B curvature drift, suggesting a magnetospheric mechanism for the black aurora. As expected, a comparison of the drift speeds with a rudimentary dipole field model of the gradient-B curvature drift speed only yields order-of-magnitude agreement, which most likely is due to the nightside disturbed magnetosphere being significantly stretched. URI: http://hdl.handle.net/10037/581 File(s) in this item: 1
article.pdf (781.5Kb) -
Romundset, Anders (Doctoral thesis; Doktorgradsavhandling, 15-Oct-2010)[+][-]
Abstract: NORSK SAMANDRAG:
Denne avhandlinga tek for seg endringane i relativt havnivå – strandforskyvinga – dei siste vel 11.500 åra på kysten av Finnmark og i midtre Hardanger. Ei stor mengd kjerneprøver frå avsettingane i innsjøar som ein gong låg under havnivået, er henta inn og analysert. Grenser mellom sediment som vart avsett i salt- eller ferskvatn er bestemt ved å analysere både kiselalgar og restar etter daude dyr og planter, og tidfest ved hjelp av radiokarbondatering. I lag med presist oppmålte høgder på innsjøtersklane, gjer desse data det mogleg å rekonstruere havnivåendringane i høg detalj. Her blir det presentert havnivåkurver som syner utviklinga i fire område; Tørvikbygd i Hardanger, Sørøya og Rolvsøya i vest-Finnmark og Nordkinnhalvøya i aust-Finnmark. Desse dokumenterer samspelet mellom landheving og havnivåstiging – stort sett har landhevinga vore sterkast, men i tida mellom ca. 9-7000 år sidan var det motsette tilfelle på finnmarkskysten – da vart fleire innsjøar atter oversvømt etter å ha lege fleire tusen år over havnivået. På Rolvsøya steig havnivået opp over ein innsjø men nådde ikkje den neste som ligg rett attmed, berre omlag 60 cm høgare. Her stabiliserte det seg i meir enn tre tusen år, fram til for ca. 5000 år sidan. Etter det har havnivået falle fleire meter fram til i dag. Ei liknande utvikling er òg funne på Sørøya og Nordkinnhalvøya, men i Tørvikbygd er historia ei anna. Her vart landet mykje hardare nedpressa mot slutten av siste istid, og landhevinga har vore tilsvarande sterk, særleg det fyrste tusenåret etter at isen forsvann – da datt strandlina gjennomsnittleg med meir enn 5 cm i året. Breen som dekte Barentshavet under siste istid, smelta vekk tidlegare enn isen over Finnmark. Dette førte til sterk heving av havbotnen som også virka inn på tidleg isfrie område av ytterkysten og medførte at spranget mellom marin grense og yngre strandliner er langt større her enn langs andre delar av norskekysten. I tillegg er bidraget til hevinga frå Barentshavet, truleg i lag med ein slakare profil på innlandsisen, årsaka til at dei heva strandlinene i Finnmark hallar mindre enn dei gjer t.d. på Vestlandet. Det er funne klåre spor etter ein tsunami i fem av innsjøane på Finnmarkskysten. Dateringar syner at dette må ha vore Storeggatsunamien, som vart utløyst av eit enormt undersjøisk skred utafor Mørekysten for om lag 8100-8200 år sidan. Bølgja slo opp i alle fall 3-4 meter i høgda, og mange hundre meter innover land. Erosjonen var sterkast nært sjøen der tsunamien grov sed ned i meir enn 3000 år eldre avleiringar. Over erosjonskontakten ligg nedst eitt sandlag, fylgd av mellom anna opprivne torvbitar og gytjeklumpar som tydeleg har rulla i sanda. Den valdsamme erosjonen og dei sorterte avsettingane tilseier at tsunamien må ha råka 17 innsjøar som ikkje var islagte, og på denne tida var klimaet vesentleg kaldare enn i dag. Dette gjer det truleg at både Storeggaskredet og tsunamien hende ein gong mellom april og oktober.Description: Paper number 1 of the thesis is not available in Munin due to publisher's restrictions:
1. Romundset, A., Lohne, Ø.S., Mangerud, J. & Svendsen, J.I.: «The first Holocene relative sea-level curve from the middle part of Hardangerfjorden, western Norway», Boreas 39(2010), 87-104 (Wiley). Available at http://dx.doi.org/10.1111/j.1502-3885.2009.00108.xURI: http://hdl.handle.net/10037/2703 File(s) in this item: 3
paper_2.pdf (6.899Mb)paper_3.pdf (3.449Mb)thesis.pdf (878.2Kb) -
Bast, Radovan; Ruud, Kenneth; Rizzo, Antonio; Helgaker, Trygve (Journal article; Tidsskriftartikkel; Peer reviewed, 2011)[+][-]
Abstract: We present the first relativistic study of the electric-field-gradient induced birefringence (Buckingham birefringence), with application to the series of molecules CX2 (X = O, S, Se, Te). A recently developed atomic-orbital-driven scheme for the calculation of time-dependent molecular properties using one-, two- and four-component relativistic wave functions (Bast et al. in Chem Phys 356:177, 2009) is extended to first-order frequency-dependent magnetic-field perturbations, using London atomic orbitals to ensure gauge-origin independent results and to improve basis-set convergence. Calculations are presented at the Hartree–Fock and Kohn–Sham levels of theory and results for CO2 and CS2 are compared with previous high-level coupled-cluster calculations. Except for the heaviest member of the series, relativistic effects are small—in particular for the temperature-independent contribution to the birefringence. By contrast, the effects of electron correlation are significant. However, the reliability of standard exchange-correlation functionals in describing Buckingham birefringence remains unclear based on the comparison with high-level coupled-cluster singles-and-doubles calculations. URI: http://hdl.handle.net/10037/4219 File(s) in this item: 1
article.pdf (372.3Kb) -
Kalogerakis, K. S.; Gustavsson, Björn Johan; Slanger, T. G.; Rietveld, Michael T; Kendall, E. A.; Pedersen, T. R.; Kosch, M. J. (Journal article; Tidsskriftartikkel; Peer reviewed, 2009)[+][-]
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Soløy, Håvard (Master thesis; Mastergradsoppgave, 03-Feb-2011)[+][-]
Abstract: På det yrkesfaglige utdanningsprogrammet Design og håndverk i videregående skole (Vg1) skal elevene arbeide med designprosessen – fra idé til produkt. Denne studien tar utgangspunkt i et tverrfaglig prosjekt i design og håndverk og matematikk. Problemstillingen var: ”Hvordan kommer elevenes representasjonskompetanse til uttrykk i arbeidet med de ulike fasene i designprosessen i et snøskulpturprosjekt?” Jeg har diskutert hvordan elevene bruker ulike representasjoner av matematikk gjennom de ulike fasene i prosessen. Analyser fra studien kan tyde på at elevene har stor grad av representasjonskompetanse i arbeidet med selve designet, men mindre grad av slik kompetanse til eksplisitt å forklare det matematiske innholdet i arbeidet med skulpturene. URI: http://hdl.handle.net/10037/3364 File(s) in this item: 1
thesis.pdf (1.325Mb) -
Trollebø, Robert (Master thesis; Mastergradsoppgave, 15-Dec-2009)[+][-]
Abstract: The origin and heating of the solar wind is still a puzzle. We review in this study the idea that the solar wind originates in coronal funnels. We place emphasis on the fast solar wind. This study provides primarily a historic overview over the development of the idea of funnel expansion. We present examples of recent solar wind studies that investigate the funnel geometry. These studies include both static and time dependent reconnection geometries. The time dependent reconnection geometry that we present and evaluate in more detail is He et al. 2008. They present their model in order to explain why blue and red shift of the spectral lines Si II, C IV and Ne VIII can be seen in the same flow tubes on the sun. We have found some of the strengths and weaknesses with this model by comparing the models results to observations and to contemporary papers that treat the same ions. We have found that the model results fit relatively well to observed Doppler shifts (velocities), but that the model ignores the physical mechanism below 5*10^6 m that transports the heavy ions to that height, and it does not fully explain the choices of initial conditions, in particular why the mass input occurs exactly at 5*10^6 m. These challenges with this model may be important to take into account when developing future models of funnels. URI: http://hdl.handle.net/10037/2406 File(s) in this item: 1
thesis.pdf (1.822Mb) -
Fernandez-Luque, Luis; Karlsen, Randi; Bonander, Jason (Journal article; Tidsskriftartikkel; Peer reviewed, 2011)[+][-]
Abstract: In recent years the Web has come into its own as a social platform where health consumers are actively creating and consuming Web content. Moreover, as the Web matures, consumers are gaining access to personalized applications adapted to their health needs and interests. The creation of personalized Web applications relies on extracted information about the users and the content to personalize. The Social Web itself provides many sources of information that can be used to extract information for personalization apart from traditional Web forms and questionnaires. This paper provides a review of different approaches for extracting information from the Social Web for health personalization. We reviewed research literature across different fields addressing the disclosure of health information in the Social Web, techniques to extract that information, and examples of personalized health applications. In addition, the paper includes a discussion of technical and socioethical challenges related to the extraction of information for health personalization. URI: http://hdl.handle.net/10037/3858 File(s) in this item: 1
article.pdf (343.6Kb) -
Kasiulis, Evaldas (Master thesis; Mastergradsoppgave, 08-Jun-2012)[+][-]
Abstract: Ring closing reactions of barbituric acid derivatives URI: http://hdl.handle.net/10037/4407 File(s) in this item: 1
thesis.pdf (2.765Mb)
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