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• 1.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Towards autonomic software product lines2011In: SPLC '11 Proceedings of the 15th International Software Product Line Conference, Volume 2, ACM Press, 2011, p. 44:1-44:8Conference paper (Refereed)

We envision an Autonomic Software Product Line (ASPL). The ASPL is a dynamic software product line that supports self adaptable products. We plan to use reflective architecture to model and develop ASPL. To evaluate the approach, we have implemented three autonomic product lines which show promising results. The ASPL approach is at initial stages, and require additional work. We plan to exploit online learning to realize more dynamic software product lines to cope with the problem of product line evolution. We propose on-line knowledge sharing among products in a product line to achieve continuous improvement of quality in product line products.

• 2.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Autonomic Software Product Lines (ASPL)2010In: ECSA '10 Proceedings of the Fourth European Conference on Software Architecture: Companion Volume / [ed] Carlos E. Cuesta, ACM Press, 2010, p. 324-331Conference paper (Refereed)

We describe ongoing work on a variability mechanism for Autonomic Software Product Lines (ASPL). The autonomic software product lines have self-management characteristics that make product line instances more resilient to context changes and some aspects of product line evolution. Instances sense the context, selects and bind the best component variants to variation-points at run-time. The variability mechanism we describe is composed of a profile guided dispatch based on off-line and on-line training processes. Together they form a simple, yet powerful variability mechanism that continuously learns, which variants to bind given the current context and system goals.

• 3.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Towards Autonomic Software Product Lines (ASPL) - A Technical Report2011Report (Other academic)

This report describes a work in progress to develop Autonomic Software Product Lines (ASPL). The ASPL is a dynamic software product line approach with a novel variability handling mechanism that enables traditional software product lines to adapt themselves at runtime in response to changes in their context, requirements and business goals. The ASPL variability mechanism is composed of three key activities: 1) context-profiling, 2) context-aware composition, and 3) online learning. Context-profiling is an offline activity that prepares a knowledge base for context-aware composition. The context-aware composition uses the knowledge base to derive a new product or adapts an existing product based on a product line's context attributes and goals. The online learning optimizes the knowledge base to remove errors and suboptimal information and to incorporate new knowledge. The three activities together form a simple yet powerful variability handling mechanism that learns and adapts a system at runtime in response to changes in system context and goals. We evaluated the ASPL variability mechanism on three small-scale software product lines and got promising results. The ASPL approach is, however, is yet at an initial stage and require improved development support with more rigorous evaluation.

• 4.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Knowledge evolution in autonomic software product lines2011In: SPLC '11 Proceedings of the 15th International Software Product Line Conference, Volume 2, New York, NY, USA: ACM Press, 2011, p. 36:1-36:8Conference paper (Refereed)

We describe ongoing work in knowledge evolution management for autonomic software product lines. We explore how an autonomic product line may benefit from new knowledge originating from different source activities and artifacts at run time. The motivation for sharing run-time knowledge is that products may self-optimize at run time and thus improve quality faster compared to traditional software product line evolution. We propose two mechanisms that support knowledge evolution in product lines: online learning and knowledge sharing. We describe two basic scenarios for runtime knowledge evolution that involves these mechanisms. We evaluate online learning and knowledge sharing in a small product line setting that shows promising results.

• 5.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Modeling Variability in Product Lines Using Domain Quality Attribute Scenarios2012In: Proceedings of the WICSA/ECSA 2012 Companion Volume, ACM Press, 2012, p. 135-142Conference paper (Refereed)

The concept of variability is fundamental in software product lines and a successful implementation of a product line largely depends on how well domain requirements and their variability are specified, managed, and realized. While developing an educational software product line, we identified a lack of support to specify variability in quality concerns. To address this problem we propose an approach to model variability in quality concerns, which is an extension of quality attribute scenarios. In particular, we propose domain quality attribute scenarios, which extend standard quality attribute scenarios with additional information to support specification of variability and deriving product specific scenarios. We demonstrate the approach with scenarios for robustness and upgradability requirements in the educational software product line.

• 6. Abbasi, R.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Limits on a muon flux from Kaluza-Klein dark matter annihilations in the Sun from the IceCube 22-string detector2010In: Physical Review D, ISSN 1550-7998, E-ISSN 1550-2368, Vol. 81, no 5, p. Article ID: 057101-Article in journal (Refereed)

A search for muon neutrinos from Kaluza-Klein dark matter annihilations in the Sun has been performed with the 22-string configuration of the IceCube neutrino detector using data collected in 104.3 days of live time in 2007. No excess over the expected atmospheric background has been observed. Upper limits have been obtained on the annihilation rate of captured lightest Kaluza-Klein particle (LKP) WIMPs in the Sun and converted to limits on the LKP-proton cross sections for LKP masses in the range 250-3000 GeV. These results are the most stringent limits to date on LKP annihilation in the Sun.

• 7. Abbasi, R.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
SEARCH FOR MUON NEUTRINOS FROM GAMMA-RAY BURSTS WITH THE IceCube NEUTRINO TELESCOPE2010In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 710, no 1, p. 346-359Article in journal (Refereed)

We present the results of searches for high-energy muon neutrinos from 41 gamma-ray bursts (GRBs) in the northern sky with the IceCube detector in its 22 string configuration active in 2007/2008. The searches cover both the prompt and a possible precursor emission as well as a model-independent, wide time window of -1 hr to + 3 hr around each GRB. In contrast to previous searches with a large GRB population, we do not utilize a standard Waxman-Bahcall GRB flux for the prompt emission but calculate individual neutrino spectra for all 41 GRBs from the burst parameters measured by satellites. For all of the three time windows, the best estimate for the number of signal events is zero. Therefore, we place 90% CL upper limits on the fluence from the prompt phase of 3.7 x 10(-3) erg cm(-2) (72 TeV-6.5 PeV) and on the fluence from the precursor phase of 2.3 x 10(-3) erg cm(-2) (2.2-55 TeV), where the quoted energy ranges contain 90% of the expected signal events in the detector. The 90% CL upper limit for the wide time window is 2.7 x 10(-3) erg cm(-2) (3 TeV-2.8 PeV) assuming an E-2 flux.

• 8. Abbasi, R.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Calibration and characterization of the IceCube photomultiplier tube2010In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 618, no 1-3, p. 139-152Article in journal (Refereed)

Over 5000 PMTs are being deployed at the South Pole to compose the IceCube neutrino observatory. Many are placed deep in the ice to detect Cherenkov light emitted by the products of high-energy neutrino interactions, and others are frozen into tanks on the surface to detect particles from atmospheric cosmic ray showers. IceCube is using the 10-in. diameter R7081-02 made by Hamamatsu Photonics. This paper describes the laboratory characterization and calibration of these PMTs before deployment. PMTs were illuminated with pulses ranging from single photons to saturation level. Parameterizations are given for the single photoelectron charge spectrum and the saturation behavior. Time resolution, late pulses and afterpulses are characterized. Because the PMTs are relatively large, the cathode sensitivity uniformity was measured. The absolute photon detection efficiency was calibrated using Rayleigh-scattered photons from a nitrogen laser. Measured characteristics are discussed in the context of their relevance to IceCube event reconstruction and simulation efforts. (C) 2010 Elsevier B.V. All rights reserved.

• 9. Abbasi, R.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Measurement of sound speed vs. depth in South Pole ice for neutrino astronomy2010In: Astroparticle physics, ISSN 0927-6505, E-ISSN 1873-2852, Vol. 33, no 5-6, p. 277-286Article in journal (Refereed)

We have measured the speed of both pressure waves and shear waves as a function of depth between 80 and 500 m depth in South Pole ice with better than 1% precision. The measurements were made using the South Pole Acoustic Test Setup (SPATS), an array of transmitters and sensors deployed in the ice at the South Pole in order to measure the acoustic properties relevant to acoustic detection of astrophysical neutrinos. The transmitters and sensors use piezoceramics operating at similar to 5-25 kHz. Between 200 m and 500 m depth, the measured profile is consistent with zero variation of the sound speed with depth, resulting in zero refraction, for both pressure and shear waves. We also performed a complementary study featuring an explosive signal propagating vertically from 50 to 2250 m depth, from which we determined a value for the pressure wave speed consistent with that determined for shallower depths, higher frequencies, and horizontal propagation with the SPATS sensors. The sound speed profile presented here can be used to achieve good acoustic source position and emission time reconstruction in general, and neutrino direction and energy reconstruction in particular. The reconstructed quantities could also help separate neutrino signals from background. (C) 2010 Elsevier B.V. All rights reserved.

• 10.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Nätverksoptimering: Bästa möjliga tillgänglighet till lägsta möjliga länkkostnad2012Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis

Denna uppsats behandlar nätverksoptimering, med fokus på att få fram den bästa möjliga tillgängligheten till lägsta möjliga kostnad, i form av länkar. I studien tas en teoretiskt grundad hypotes om en metod fram för att lösa detta problemet. Samt genomförs ett test där metoden appliceras på ett studieobjekt för att bekräfta huruvida metoden verkar fungerar eller inte.

Resultatet blir slutligen en metod som genom att analysera tillgängligheten, länk redundansen samt beräkna antal oberoende vägar mellan noder i ett nätverk. Kan genom att jämföra resultat från före en förändring med resultat från efter en förändring lyfta fram de förändringar som medför förbättringar. Varpå ett nätverk kan optimeras till bästa möjliga tillgänglighet till lägsta möjliga kostnad, i form av länkar.

• 11.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Space Time Coding For Wireless Communication2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

As the demand of high data rate is increasing, a lot of research is being conducted in the field of wireless communication. A well-known channel coding technique called Space-Time Coding has been implemented in the wireless Communication systems using multiple antennas to ensure the high speed communication as well as reliability by exploiting limited spectrum and maintaining the power. In this thesis, Space-Time Coding is discussed along with other related topics with special focus on Alamouti Space-Time Block Code. The Alamouti Codes show good performance in terms of bit error rate over Rayleigh fading channel. The performance of Altamonte’s code and MIMO capacity is evaluated by using MATLAB simulation.

• 12.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Geometri: Hur lärare undervisar i geometri i de tidigare skolåren2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis

A number of both international and national enquires shows that Swedish pupils are getting worse results in mathematics. One area that’s frequently pointed out is geometry. This enquiry intends to find out how the subject of geometry has developed in the Swedish school and witch methods and concepts teachers who teach in preschool and the early school years grade use in their teaching. This enquiry is based upon eight semi structured interviews and from studying previous curriculums. The result shows that teachers use a great deal of concepts and methods in their teaching but that there are a need for further education among teachers. The enquiry also shows that the significance of the subject has changed over time.

• 13.
Tokyo University of Science, Japan.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Tokyo University of Science, Japan.
A Fair sampling test for Ekert protocol2011In: Quantum Bio-inforamtics IV: From Quantum Information to BioInformatics / [ed] Luigi Accardi, Wolfgang Freudenberg, Masanori Ohya, World Scientific, 2011, p. 403-412Chapter in book (Refereed)
• 14.
Oslo University.
Tokyo University of Science. Tokyo University of Science. Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Double Blinding-Attack on Entanglement-Based Quantum Key Distribution Protocols2012In: AIP Conference Proceedings, ISSN 0094-243X, E-ISSN 1551-7616, Vol. 1424, no 1, p. 9-16Article in journal (Refereed)

We propose a double blinding-attack on entangled-based quantum key distribution protocols. The principle of the attack is the same as in existing blinding attack except that instead of blinding the detectors on one side only, Eve is blinding the detectors of both Alice and Bob. In the BBM92 protocol, the attack allows Eve to get a full knowledge of the key and remain undetected even if Alice and Bob are using 100% efficient detectors. The attack can be easily extended to Ekert protocol, with an efficiency as high as 85.3%.

• 15.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Kommunal verksamhetsprocess efter införandet av en e-tjänst: Informationsflöde och informationshantering sett ur ett Lean-perspektiv2011Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis

Trots de svenska medborgarnas ökande krav på digital självservice via e-tjänster, går införande trögt hos kommunerna. En anledning är den relativt låga kunskap som finns i området. Främst vad gäller avancerade e-tjänster som förutom att öka medborgarnas tillgänglighet, insyn och delaktighet i sina offentliga ärenden, även ska minska den administrativa hanteringen för att istället låta mer av resurserna gå till kärnverksamheten. I den här kvalitativa fallstudien studerades hur en kommunal verksamhetsprocess utvecklas vid införandet av en e-tjänst. Hur slöseri kan identifieras i processen informationshantering och informationsflöde och hur dessa förändrats efter att e-tjänsten införts. Resultatet baserades på material från intervjuer och analyserades utifrån Leans kategorier av slöseri och teorin om Microsystem. Resultatet visade att slöseri som uppstår i informationshantering och informationsflöde mellan enheter eller microsystem kunde identifieras om alla microsystem kartlägger processen tillsammans. Mycket slöseri hade tagits bort i utvecklingsarbetet och lett till en smidigare och troligtvis mer effektiv process. Ett antagande men som även bekräftades av personalens upplevelser från testförsöken. Processutvecklingen tillsammans med e-tjänsten har säkerställt delar av processflödet där antalet informationsöverföringar blivit färre och på så sätt troligtvis även minskat risken för att missförstånd och felhantering ska uppstå av informationshanteringen.

• 16.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Design and simulation of beam steering for 1D and 2D phased antenna arrays using ADS.2012Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis

Phased arrays eliminate the problems of mechanical steering by using fast and reliable electronic components for steering the main beam. Modeling and simulation of beam steering for 1D and 2D arrays is the aspect that is considered in this thesis. A 1D array with 4 elements and a 2D array with 16 elements are studied in the X-band (8-12 GHz). The RF front-end of a phased array radar is modeled by means of ADS Momentum (Advanced design system).

• 17.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Att fånga en oskuld: En undersökning kring ungdomars intresse för ekonomisk information online2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

Att vid 18 års ålder tvingas ansvara för sina handlingar är för många ett stort steg, inte minst då en del av ansvaret är ekonomi. Ungdomarna vänder sig ofta till föräldrarna med frågor, men var ska de vända sig när föräldrarna inte har svaret? Bankerna har börjat söka sig lägre ner i åldrarna med sin marknadsföring för att fånga kunden innan denne blir myndig, men fortfarande är det många frågetecken kring informationen ungdomarna behöver.

Uppdraget var att undersöka vad ungdomar behöver för information i en webbplats riktad mot ungdomar från banken. En undersökning genomfördes med en enkätundersökning med 100respondenter och tre olika fokusgrupper som genererade att ungdomarna känner att banker är alldeles för avlägsna. En minskad distans skulle medföra att ungdomarna lättare vänder sig till banken vid frågor kring sin ekonomi vilket i sin tur medför att deras intresse kring privatekonomiska frågor ökar.

Designförslaget som presenteras fokuserar mycket på en funktion med textbaserad personlig service med co-browsingfunktioner som tillåter en bankman guida den unga kunden genom webbplatsen. Strävan är att ungdomarna ska känna en samhörighet till banken och lättare kan få alla typer av frågor besvarade då de var osäkra på vilken information de behöver. Om man inför en sådan tjänst bör användbarhetstest och utvärderingar på designförslaget genomföras för att kontrollera om distansen mellan bank och ungdom minskar.

• 18.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Elevers möjlighet att utveckla matematiska förmågor utifrån läromedlet Pixel2012Student paper other, 10 credits / 15 HE creditsStudent thesis

Syftet med arbetet är att ta reda på i vilken utsträckning elever ges förutsättningar att utveckla de olika förmågor som beskrivs i kursplanen för ämnet matematik, LGR11, när undervisningen bygger på ett vanligt förekommande läromedel, Pixel. Metoden är kvalitativ och det har skett en textanalys på geometriavsnitten i läromedlet. De förmågor som eleverna når upp till är att använda sig av olika matematiska begrepp, samt att formulera och lösa problem. Eleverna har goda möjligheter att själva kunna välja olika sätt att lösa uppgifter. De får även kunskap att förstå och använda olika uttrycksformer. Eleverna uppmuntras inte med hjälp av detta läromedel, att föra egna matematiska diskussioner.

• 19.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Identifiering och visualisering av aktuella ämnen och sociala relationer i ett mikrobloggnätverk.: Riksdagspartiernas twitteranvändning inför riksdagsvalet 20102010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

Att enskilda politiker och partier väljer att använda sig av sociala medier i valsammanhang blir allt vanligare. I denna uppsats granskades de svenska riksdagspartiernas twitteranvändning inför det svenska riksdagsvalet 2010. Genom en social- och innehållsmässig analys kring twitteranvändandet kunde enskilda partiers kommunikationsmönster anas. Den sociala analysen baserades på relationen mellan en användares följare och följande, den innehållsmässiga på de taggar nätverkets mikroblogginlägg märkts med.

Bland annat identifierades två partier med en ren tvåvägskommunikation, och ett parti med en klar envägskommunikation. Två av de undersökta partierna hade även tendenser till att rikta sin kommunikation mot en inre grupp av politiska twittrare. Den innehållsmässiga analysen pekade även på att de olika partiernas nätverk till viss del har en liknande sammansättning, politikerna hade en tendens att följa varandra och partispecifika taggar dök upp i samtliga av de analyserade partiernas nätverk. Datan använd i analysen hämtades med hjälp av en utvecklad prototyp.

• 20.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Modeling and Simulation of an Electrostatic Precipitator Including a Comsol Multiphysics Guide for Modeling an ESP2011Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis

Gaseous exhaust of different industries contains dust particles of different chemical precipitates that are harmful for the environment. Electrostatic Precipitators are very often used in industries to filter their gaseous exhaust and to prevent the atmosphere to being polluted. Electrostatic Precipitators are very efficient in their work. Electrostatic Precipitators use the force of the electric field to separate the dust particles from gaseous exhaust. Electrostatic Precipitators charge the dust particles and remove these particles by attracting these charged dust particles toward the collecting plates. The charging of dust particles requires a charging zone. When gas passes through that charging zone, the dust particles in the gas stream become charged and then these charged particles are attracted toward the collecting plates. The design of an Electrostatic Precipitators requires the knowledge of its working principle and the problems that often arise during its working. This thesis is the study of the working and the problems of the Electrostatic Precipitators. The main reason for problems in working of an Electrostatic Precipitator is the dust resistivity. This dust resistivity affects the collection performance of an Electrostatic Precipitator. This thesis also contains the simulation of an Electrostatic Precipitator. In the simulation part, the Electric Potential and the Electric Field of an ESP is modeled in an ideal condition, when no gas is flowing through the ESP. The industrial software Comsol Multiphysics is used for the simulation. A Comsol Multiphysics guide is given in appendix of this thesis report that provides information about using this software.

• 21.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
CUBIC CONGRUENCE EQUATIONS2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

Let Nm(f(x)) denote the number of solutions of the congruence equation f(x)≡0 (modm), where m≥2 is any composite integer and f(x) is a cubic polynomial. In this thesis, we use different theorems and corollaries to find a number of solutions of the congruence equations without solving then we also construct the general expression of corresponding congruence equations to demonstrate the solutions of the equations. In this thesis, we use Mathematica software as a tool.

• 22.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Classification of perfect codes and minimal distances in the Lee metric2010Independent thesis Advanced level (degree of Master (Two Years)), 15 credits / 22,5 HE creditsStudent thesis

Perfect codes and minimal distance of a code have great importance in the study of theoryof codes. The perfect codes are classified generally and in particular for the Lee metric.However, there are very few perfect codes in the Lee metric. The Lee metric hasnice properties because of its definition over the ring of integers residue modulo q. It isconjectured that there are no perfect codes in this metric for q > 3, where q is a primenumber.The minimal distance comes into play when it comes to detection and correction oferror patterns in a code. A few bounds on the number of codewords and minimal distanceof a code are discussed. Some examples for the codes are constructed and their minimaldistance is calculated. The bounds are illustrated with the help of the results obtained.

• 23.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Local orthogonal mappings and operator formulation for varying cross-sectional ducts.2010Independent thesis Advanced level (degree of Master (Two Years)), 15 credits / 22,5 HE creditsStudent thesis

A method is developed for solving the two dimensional Helmholtz equation in a ductwith varying cross-section region bounded by a curved top and flat bottom, having oneregion inside. To compute the propagation of sound waves in a curved duct with a curvedinternal interface is difficult problem. One method is to transform the wave equation intoa solvable form and making the curved interface plane. To this end a local orthogonaltransformation is developed for the varying cross-sectional duct having one medium inside.This transformation is first used to make the curved top of the waveguide flat andto transform the Helmholtz equation into an initial value problem. Later on the local orthogonaltransformation is developed for a waveguide having two media inside with flattop, a flat bottom and a curved interface. This local orthogonal transformation is used toflatten the interface and also to transform the Helmholtz equation into a simple, solvableordinary differential equation. In this paper we present operator formulation for the partwith flat bottom and curved top including a curved interface. In the ordinary differentialequation with operators in coefficients, obtained after the transformation, all the operationsrelated to the transverse variable are treated as operators while the derivative withrespect to the range variable is kept.

• 24.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Promotion of Knowledge Sharing culture at local branch of a global Professional Services Firm: an Exploratory Case Study2011Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis

Professional Services Firms promote knowledge sharing cultures to maintain consistency in the internal flow of organizational knowledge. Building a knowledge sharing culture takes tough time. Enterprises make lot of efforts to share knowledge in effective way by adjusting the influencing factors like changing the organisational structure and culture, motivation and evaluation mechanism etc. Any knowledge management strategy designed to improve business performance must address the component “organizational culture” that includes behaviours, norms and practices. Organisation needs to promote knowledge sharing by adopting various methods for motivating employees, so they successfully diffuse their knowledge.The purpose of this case study was to explore the different issues faced by global Professional Services Firms while promoting knowledge sharing culture at their local branch. It was interesting to figure out that how a global „Professional Services Firm‟ promotes knowledge sharing culture at their local branch. Aim was also to highlight how these firms can change employee‟s „knowledge-hoarding behaviours‟ to „knowledge-sharing behaviours’ with the help of incentives and rewards.A qualitative exploratory case study was conducted by adopting social constructivist worldview. The research settings for our research were the Ernst & Young (Växjö) branch. Data was collected through observations and interviews. To assist the data collection phase, we have taken permission to observe their daily practises of knowledge sharing twice in a month.The main findings conclude that „Working as a unit‟ and „spirit of helping everyone‟ is a key to promote knowledge sharing culture at global Professional Services Firm‟s local branches. „Low power distances‟ as in „Nordic culture‟ provides solid platform for global Professional Services Firms to promote knowledge sharing culture. This is actually a good way of promoting knowledge sharing culture by decreasing level gap. Findings show that by decreasing level gaps and helping juniors, knowledge can become organisational rather than individual. Our investigation indicates that this local branch hasn‟t adopted any incentive programmes specifically for knowledge sharing. They are managing knowledge sharing with Nordic or Swedish way of working. Non-monetary incentives can be useful to motivate and reinforce specific behaviours of individuals. It can also helpful to boost up cooperative behaviours while working in teams. Professional Services Firms can win the battle of developing a true knowledge sharing culture by working as a unit, reducing power distances and motivating employees.

• 25.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
A Multi-Dimensional Knowledge ManagementSystems Planning Approach2010In: Journal of information & knowledge management, ISSN 0219-6492, Vol. 09, no 03, p. 291-302Article in journal (Refereed)
• 26.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Exploring learning in Patient-centered care2011In: Americas conference on information systems, 2011, 2011Conference paper (Refereed)
• 27.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Patient-Centered Care as a Learning Process2012In: Electronic Healtcare: 4th International Conference, eHealth 2011, Málaga, Spain, November 21-23, 2011, Revised Selected Papers / [ed] P. Kostkova, M. Szomszor, and D. Fowler, Springer, 2012, p. 85-92Conference paper (Refereed)
• 28.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Simulation of Phased Arrays with Rectangular Microstrip Patches on Photonic Crystal Substrates2012Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis

This thesis describes the investigation of photonic crystals as a substrate in microstrip phased array antennas. Alumina with a relative dielectric constant of 9.6 is used as substrate to obtain miniaturization of the components in the high-frequency range. The proposed design consists of four rectangular patches in a linear array conguration operating at 12 GHz. The antenna elements are excited by a microstrip feed line using the inset feeding technique for perfect impedance matching. A beam steering of 20o is achieved using a switched line phase shifter. Antenna parameters, including impedance matching, bandwidth, gain, directivity and the S parameters of the proposed array antenna are obtained. The simulation results are obtained with the Advanced Design System (ADS) simulator.

• 29.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Honeypots in network security2010Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis

Day by day, more and more people are using internet all over the world. It is becoming apart of everyone’s life. People are checking their e-mails, surfing over internet, purchasinggoods, playing online games, paying bills on the internet etc. However, while performingall these things, how many people know about security? Do they know the risk of beingattacked, infecting by malicious software? Even some of the malicious software arespreading over network to create more threats by users. How many users are aware of thattheir computer may be used as zombie computers to target other victim systems? Astechnology is growing rapidly, newer attacks are appearing. Security is a key point to getover all these problems. In this thesis, we will make a real life scenario, using honeypots.Honeypot is a well designed system that attracts hackers into it. By luring the hackerinto the system, it is possible to monitor the processes that are started and running on thesystem by hacker. In other words, honeypot is a trap machine which looks like a realsystem in order to attract the attacker. The aim of the honeypot is analyzing, understanding,watching and tracking hacker’s behaviours in order to create more secure systems.Honeypot is great way to improve network security administrators’ knowledge and learnhow to get information from a victim system using forensic tools. Honeypot is also veryuseful for future threats to keep track of new technology attacks.﻿

• 30. Aksimsek, Sinan
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
TEM wave propagation in a coaxial cable with a step discontinuity on the outer wall2012Report (Other academic)
• 31. Albeverio, S
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Theory of p-adic distributions: linear and nonlinear models2010Book (Refereed)
• 32.
University of Bonn, Institute of Applied Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. University of Warwick, Department of Statistics.
Uniform Asymptotic Bounds for the Heat Kernel and the Trace of a Stochastic Geodesic Flow2012In: Stochastics: An International Journal of Probablitiy and Stochastic Processes, ISSN 1744-2508, E-ISSN 1744-2516, Vol. 84, no 2-3, p. 315-333Article in journal (Refereed)

We analyze the asymptotic behaviour of the heat kernel dened by a stochastically perturbedgeodesic ow on the cotangent bundle of a Riemannian manifold for small time and smalldiusion parameter. This extends WKB-type methods to a particular case of a degenerateHamiltonian. We give uniform bounds for the solution of the degenerate Hamiltonian boundaryvalue problem for small time. The results are exploited to derive two sided estimates andmultiplicative asymptotics for the heat kernel semigroup and its trace.

• 33. Albeverioa, S.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
The Cauchy problems for evolutionary pseudo-differential equations over p-adic field and the wavelet theory2011In: Journal of Mathematical Analysis and Applications, ISSN 0022-247X, E-ISSN 1096-0813, Vol. 375, no 1, p. 82-98Article in journal (Refereed)
• 34.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Displayintegrering2010Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis

This abstract describes the Bachelor of Science in engineering thesis for computer science at Linnaeus University. Arcoma AB in Växjö is a company that constructs and develops complete x-ray systems. The goal of the company is to improve the usability of the system with the help of a LED display. Arcoma can improve the system by exchange the unit that controls the x-ray generator with the LED display instead. This will give the user the ability to have better overview and control of the system, while treating the patient.

This report describes the implementation of both the software and the hardware for the display, but also the technical background for some standards like HDMI and the LED technologic. The software has been tested directly to the display, and therefore made the testing interesting. We have used the Arcoma system and the development tools to solve the problem. The programming language that was used to solve the problem was mainly C++.

The result was a system that is build up by the Arcoma hardware platform, our surrounding electronics and the display where the last ones were built in a box. Aside the display a demo application was developed for controlling the generator. This applications is controlled by a USB mouse. Arcoma is pleased with the result of the main problem with the display, and they are also pleased with us solving the additional problems that existed. Arcoma wants to create a demand of this solution in their new products.

• 35.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Visualization of gene ontology and cluster analysis results2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

The purpose of the thesis is to develop a new visualization method for Gene Ontologiesand hierarchical clustering. These are both important tools in biology andmedicine to study high-throughput data such as transcriptomics and metabolomicsdata. Enrichment of ontology terms in the data is used to identify statistically overrepresentedontology terms, that give insight into relevant biological processes orfunctional modules. Hierarchical clustering is a standard method to analyze andvisualize data to nd relatively homogeneous clusters of experimental data points.Both methods support the analysis of the same data set, but are usually consideredindependently. However, often a combined view such as: visualizing a large data setin the context of an ontology under consideration of a clustering of the data.The result of the current work is a user-friendly program that combines twodi erent views for analysing Gene Ontology and Cluster simultaneously. To makeexplorations of such a big data possible we developed new visualization approach.

• 36.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Om informationslogistik är svaret. Vad är frågan?2010Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis

The purpose of this study is to identify information logistical problems and needs in work of change. This within the following work of change areas, strategy, organization and IT. And thereby show what kind of problem and needs information logistics can solve. The reason of choosing these work of change areas is because that information logistics is a multidisciplinary subject. That include informatics, logistics and economy/management.

The research within information logistics show how IT can be used for a user – demand information supply. In summary the research area expresses how information can be stored in data warehouse and can be processed with business intelligence. The underlying approach of how different IT solutions can give the right information to the right person at the right time is logistics. The research area show different perspectives of information logistic and what the word refer to. The question is of there is any relevance and use for organizations to handle information logistic.

The method of this study is based on Grounded Theory. Whose purpose is to let the collected empirics navigate the studies theoretical framework of references. Which in the context are most suitable. The approach of this study is hermeneutic with a qualitative method. The empirical groundwork has been collected through telephone interviews with special advisers such as consultants. Within scope of consulting services as strategy, organization and IT.  Through the analysis it has been identified that it within a work of change exist three types of information flows.

• Structured information flow.
• Restructured information flow.
• Unstructured information flow.

Besides above information flow it has also been identified situations where the information is dynamic respective stable. The analysis has therefore made a difference between the flow of information and the information as such. The following terms will show problems that are regarded as information logistics

• The information is seperated from the users demand.
• Cannot reach out with the information that is on paper.
• Management wants information in one way and the co-worker on another.
• Consultants take over information management.
• Organization of process and people
• The information is kept separated and affect process execution.

• 37.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
3D Virtual Shopping Mall: Towards Transformation of levels from 2D to 3D2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

This research examines the effects of using 3D virtual shopping malls and shows the user interaction and experience in this type of virtual environments. Technology developments and the use of the Internet made users to expect more services, which help to improve the user's life. Using a 3D virtual environment and adding a shopping idea to it is considered as very interesting, especially if it reflects the real world in a virtual reality that make its users attached to it. Furthermore, the possibility of having an avatar to represent themselves in computer-mediated virtual environment help users to explore the virtual environment. Another advantage is that users have the possibility to invite friends and to navigate inside a 3D Virtual-shopping mall not alone but together, which gives the user the capability to socialise inside the mall. Besides, changing of the customer's profile and chatting with friends is supported, too. Moreover, the transformation process from a two-dimensional environment to a three-dimensional environment is considered to be convenient for both, customers and mall owners.

I have used phenomenology to investigate this new phenomenon. In addition the data was gathered by interviewing several participants from different educational levels as well as business owners of 3D virtual malls. The research will show the potential of using a 3D virtual shopping mall from the user's perspective as well as from the business' owners and having a 3D virtual shopping mall is not only considered entertaining, but also convenient.

As a future work I recommend to interview the merchants in this research to grasp this idea completely.

• 38.
Dept. of Comput. Intell. & Syst. Sci., Tokyo Inst. of Technol., Tokyo, Japan.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Adaptive Systems Research Group, University of Hertfordshire, Hatfield, UK. Adaptive Systems Research Group, University of Hertfordshire, Hatfield, UK. Adaptive Systems Research Group, University of Hertfordshire, Hatfield, UK.
Helping Robots Imitate: Metrics And Computational Solutions Inspired By Human-Robot Interaction Studies2010In: Advances in Cognitive Systems / [ed] Samia Nefti-Meziani and John Gray, Institution of Engineering and Technology, 2010, p. 127-167Chapter in book (Refereed)

In this chapter we describe three lines of research related to the issue of helping robots imitate people. These studies are based on observed human be- haviour, technical metrics and implemented technical solutions. The three lines of research are: (a) a number of user studies that show how humans naturally tend to demonstrate a task for a robot to learn, (b) a formal approach to tackle the problem of what a robot should imitate, and (c) a technology-driven conceptual framework and technique, inspired by social learning theories, that addresses how a robot can be taught. In this merging exercise we will try to propose a way through this prob- lem space, towards the design of a Human-Robot Interaction (HRI) system able to be taught by humans via demonstration.

• 39.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Employees' Role in Improving Information Systems Security2011Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis

Information security is one of the most essential concerns in today’s organizations. IT departments in larger organizations are tasked to implement security, by both ensuring to have pertinent hardware and software, and likewise enlighten, teach and educate organization’s employees about security issues. The aim of this research is to focus on the human factor of the organization, which impacts the security of the information, since technological solutions of technical problems become incomprehensible without human recognition about security. If the security is not addressed in firms, this might lead to essential data of the organization to be compromised. This study explores ways to enhance information security and improve the human factor by integrating the crucial information security elements in organizations. Social constructivist worldview is adopted throughout the study, and an inductive based - qualitative approach, a single case study design and hermeneutical analysis for analyzing the observations and interviews are utilized. The research setting for this study is Växjö Municipality in Sweden. The empirical investigation suggests that human factor plays an essential role in maintaining information security, and organizations can improve employees’ role by keeping their security policies up to date and find the best ways to disseminate that information. As a result, this research comes up with “information security human management model” for organizations.

• 40.
Linnaeus University, Faculty of Science and Engineering, School of Engineering.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Dynamic and Cost-effective Maintenance Decisions2010In: E-maintenance / [ed] Kenneth Holmberg, London: Springer, 2010, 1, p. 345-390Chapter in book (Refereed)

In general, all the elements involved in a production process, such as tools, machinery, methods, competence and working environment are exposed to changes. Thus, to maintain and improve company profitability and competitiveness, it is necessary to reduce losses through maintaining and improving the quality of the elements involved in the production process. Therefore, the maintenance strategy applied should be dynamic to be suited for all these changes cost-effectively. In producing companies, the accuracy of maintenance decisions is essential for reducing economic losses generated due to unnecessary stoppages in companies of intensive capital investment where stoppage time is expensive, especially in paper and pulp mills, refineries, power stations and engineering manufacturing. Therefore, it is necessary for maintenance and production managers to have a system providing the data required to achieve dynamic and cost-effective maintenance decisions.

In this chapter, the new maintenance decision support system (MDSS) for achieving dynamic and cost-effective maintenance decisions developed in Chapter 12 is tested and discussed. The developed system is MIMOSA compatible, consists of three toolsets and five software modules for performing six services to achieve different objectives, e.g.:

1. higher accuracy of maintenance decisions;

2. selection of the most cost-effective maintenance solutions;

3. identification and prioritisation of problem areas and assessment of losses in production time; and

4. mapping, follow up and assessment of maintenance cost-effectiveness (maintenance savings and profit) to achieve continuous and cost effective improvement.

• 41.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
A Study Of Multipath Wave Propagation Using Nero2d and FFT2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

In this report, the Fast Fourier Transform is described briefly. An implementation, inthe form of the Fortran code four1, is tested to verify the accuracy. A two-ray modelfor wave propagation above a flat earth is discussed. The case with AM modulation isimplemented in a Mathematica script. Calculations of the surface current density, withthe program NERO, are made to test the accuracy. The transient scattering from a PECcylinder is studied by means of the code run_nero that runs NERO repeatedly. From aspectrum calculated in this way, the impulse response is obtained by Fourier inversion.

• 42.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Testkrets för lavingenombrott för högspännings diod2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis

High frequency power converters are used for both consumer products and in industrial power plants. In some industrial applications, a very high output voltage can be obtained. A transformer gives a high voltage in the secondary, which is then rectified by diodes. High voltage diodes are important components in the rectifier to withstand tough work so that the transformer supplying the desired high voltage.

Alstom in Växjö is working with Air Pollution Control Equipment. They develop marketing and executing projects with advanced systems and products for smoke gas cleaning to power plants and the industry. The objective is to minimize the risk of negative impact on the environment. In Växjö, Alstom also has a large unit for service, which also consists of several local offices covering all parts of the country.

Another important facility in Växjö is Alstom's global research and development center, where new environmental solutions and technologies are tested in large scale format. The test center has a long tradition of environmental control systems, but during the past decade the center has been one important platform for the development of Alstom’s products for carbon particle separation (electrostatic filter). These electrostatic filters use diodes as the main component of a high frequency transformer. The diodes must be specially designed to withstand high voltages. The development of the Alstom invented a new type of power diode.  The idea is that the diode is withstand of 10kV in the reverse direction.

The goal of this work is based on building a facility to test the new diode and see how the diode works with high voltage in the reverse direction condition.

• 43.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
A Differentiable Approach to Stochastic Differential Equations: the Smoluchowski Limit Revisited2012Doctoral thesis, comprehensive summary (Other academic)

In this thesis we generalize results by Smoluchowski [43], Chandrasekhar[6], Kramers, and Nelson [30]. Their aim is to construct Brownian motion as a limit of stochastic processes with differentiable sample paths by exploiting a scaling limit which is a particular type of averaging studied by Papanicolao [35]. Their construction of Brownian motion differs from the one given by Einstein since it constitutes a dynamical theory of Brownian motion. Nelson sets off by studying scaled standard Ornstein-Uhlenbeck processes. Physically these describe classical point particles subject to a deterministic friction and an external random force of White Noise type, which models perpetuous collisions with surrounding(water) molecules. Nelson also studies the case when the particles are subject to an additional deterministic nonlinear force. The present thesis generalizes the work of Chandrasekhar in that it deals with finite dimensional α-stable Lévy processes with 0 < α < 2, and Fractional Brownian motion as driving noises and mathematical techniques like deterministic time change and a Girsanov theorem. We consider uniform convergence almost everywhere and in $L^2$-sense. In order to pursue the limit we multiply all vector fields in the cotangent space by the scaling parameter including the noise. For α-stable Lévy processes this correspondsto scaling the process in the tangent space, $v_{t}$, $t\geq 0$, according to $\beta v_{t}=v_{\beta^{\alpha}t}$. Sending β to infinity means sending time to infinity. In doing so the noise evolves with a different speed in time compared to the component processes. For α≠2, α-stable Lévy processes are of pure jump type, therefore the approximation by processes having continuous sample paths constitutes a valuable mathematical tool. α-stable Lévy processes exceed the class studied by Zhang [46]. In another publication related to this thesis we elaborate on including a mean-field term into the globally Lipschitz continuous nonlinear part of the drift while the noise is Brownian motion, whereas Narita [28] studied a linear dissipation containing a mean-field term. Also the classical McKean-Vlasov model is linear in the mean-field. In a result not included in this thesis the scaling result of Narita [29], which concerns another scaling limit of the tangent space process (velocity) towards a stationary distribution, is generalized to α-stable Lévy processes. The stationary distribution derived by Narita is related to the Boltzmann distribution. In the last part of this thesis we study Fractional Brownian motion with a focus on deriving a scaling limit of Smoluchowski-Kramers type. Since Fractional Brownian motion is no semimartingale the underlying theory of stochastic differential equations is rather involved. We choose to use a Girsanov theorem to approach the scaling limit since the exponent in the Girsanov denvsity does not contain the scaling parameter explicitly. We prove that the Girsanov theorem holds with a linear growth condition alone on the drift for 0 < H < 1, where H is the Hurst parameterof the Fractional Brownian motion.

• 44.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Nelson-type Limits for α-Stable Lévy Processes2010Licentiate thesis, comprehensive summary (Other academic)

Brownian motion has met growing interest in mathematics, physics and particularly in finance since it was introduced in the beginning of the twentieth century. Stochastic processes generalizing Brownian motion have influenced many research fields theoretically and practically. Moreover, along with more refined techniques in measure theory and functional analysis more stochastic processes were constructed and studied. Lévy processes, with Brownian motionas a special case, have been of major interest in the recent decades. In addition, Lévy processes include a number of other important processes as special cases like Poisson processes and subordinators. They are also related to stable processes.

In this thesis we generalize a result by S. Chandrasekhar [2] and Edward Nelson who gave a detailed proof of this result in his book in 1967 [12]. In Nelson’s first result standard Ornstein-Uhlenbeck processes are studied. Physically this describes free particles performing a random and irregular movement in water caused by collisions with the water molecules. In a further step he introduces a nonlinear drift in the position variable, i.e. he studies the case when these particles are exposed to an external field of force in physical terms.

In this report, we aim to generalize the result of Edward Nelson to the case of α-stable Lévy processes. In other words we replace the driving noise of a standard Ornstein-Uhlenbeck process by an α-stable Lévy noise and introduce a scaling parameter uniformly in front of all vector fields in the cotangent space, even in front of the noise. This corresponds to time being sent to infinity. With Chandrasekhar’s and Nelson’s choice of the diffusion constant the stationary state of the velocity process (which is approached as time tends to infinity) is the Boltzmann distribution of statistical mechanics.The scaling limits we obtain in the absence and presence of a nonlinear drift term by using the scaling property of the characteristic functions and time change, can be extended to other types of processes rather than α-stable Lévy processes.

In future, we will consider to generalize this one dimensional result to Euclidean space of arbitrary finite dimension. A challenging task is to consider the geodesic flow on the cotangent bundle of a Riemannian manifold with scaled drift and scaled Lévy noise. Geometrically the Ornstein-Uhlenbeck process is defined on the tangent bundle of the real line and the driving Lévy noise is defined on the cotangent space.

• 45.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Differentiable Approximation by Solutions of Newton Equations Driven by Fractional Brownian Motion.Manuscript (preprint) (Other academic)

We derive a Smoluchowski-Kramers type scaling limit for second order stochastic differential equations driven by Fractional Brownian motion.We show a Girsanov theorem for the solution processes with respect to corresponding Fractional Ornstein-Uhlenbeck processes which are Gaussian. This reveals existence of weak solutions as well as a weak scaling limit. Subsequently the results are strengthened.

• 46.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Department of Statistics, University of Warwick, CV4 7AL, UK.
Nelson-type Limit for a Particular Class of Lévy Processes2010In: AIP Conference Proceedings; 1232 / [ed] Andrei Yu. Khrennikov, AIP , 2010, Vol. 1232, p. 189-193Conference paper (Other academic)

Brownian motion has been constructed in different ways. Einstein was the most outstanding physicists involved in its construction. From a physical point of view a dynamical theory of Brownian motion was favorable. The Ornstein-Uhlenbeck process models such a dynamical theory and E. Nelson amongst others derived Brownian motion from Ornstein-Uhlenbeck theory via a scaling limit. In this paper we extend the scaling result to α-stable Lévy processes.

• 47.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics. Department of Statistics, Warwick University.
Smoluchowski-Kramers Limit for a System Subject to a Mean-Field DriftManuscript (preprint) (Other academic)

We establish a scaling limit for autonomous stochastic Newton equations, the solutions are often called nonlinear stochastic oscillators,where the nonlinear drift includes a mean field term of Mckean type and the driving noise is Gaussian. Uniform convergence in $L^{2}$ sense is achieved by applying $L^{p}$-type estimates and the Gronwall Theorem.The approximation is also called Smoluchowski-Kramers limit and is a particular averaging technique studied by Papanicolaou. It reveals an approximation of diffusions with a mean-field contribution in the drift by diffusions with differentiable trajectories.

• 48.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Förberedelse till modernisering av styrsystem för produktion av processvatten2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis

The heat and power station Allöverket in Kristianstad produced the process water in a plant called the total desalination. In this plant which consists out of two identical lines, they let the incoming water passing through ion exchangers to replace the undesired ions in the water to more desired ions. The reason for doing this is that the undesired ions in the water give coatings on the turbine. When the ion exchangers have been saturated, they must be restored to the original condition. This is done by starting a regeneration program, which consists of a number of steps such as back flushing, intake of chemicals and four different flushes. There are limits on the conductivity and the content of silicon in the water that will be delivered. But there is only measurement of the conductivity connected to the control system, and because of this they control the plant with different timers. To the control system there is connected a number of centrifugal pumps, solenoid valves and instrumentation for measurement of conductivity. In the total desalination sits a Siemens S5 control system that controls the plant after amount of water, conductivity and different times of the sequences. The control functions are now located on a control cabinet out of the factory. The Siemens S5 control system is old and outdated and will be changed to an ABB 800xA control system. This control system they already use to control other parts of the factory from the control room. With this study I have developed a new functional description of the plant and it consists of function diagrams which describes how the software controls the plant today. To the function description, I have also made a new technical description and revised the process scheme so that all documentation of the plant says the same thing.

• 49.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
Underhåll och övervakning av distributionstransformatorer2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis

Följande projekt går i korthet ut på att avgöra om användning av kylsystemet i en transformatorstation är relevant, om det minimerar temperaturhöjningen orsakad av effektförlusterna som transformatorn avger. Arbetet ska resultera i förslag på val av transformatorer samt beskriva dess egenskaper. Vidare vill vi finna lösningar kring problemet med överhettning i transformatorstationerna och att de generella kraven såsom låg ljudnivå och tillräcklig ventilation (för att ta bort den värmeförlust som de inre komponenterna avger) skall uppfyllas.  För att kunna ge olika förslag på val av transformator i transformatorstationerna har vi på Holtab AB utfört olika beräkningar som visar skillnad för pris, kvalitet, livslängd och egenskaper (effektförluster, energiförluster).

• 50.
Linnaeus University, Faculty of Science and Engineering, School of Computer Science, Physics and Mathematics.
online assignment submission2011Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis

The main goal of this thesis is to design and implement online assignment submission and provide an interface use for uploading test program (Nant script file) by instructors, who would be able to evaluate assignments automatically.

The system provides an interface for testing assignments such that they can be plugged in by the teachers.  This testing could invoke a compiler and make a test-run of the compiled code and check the result or test for plagiarism, existence of certain documents or simply check the file type (extension).

The most obvious advantage offered by online assignment submission is that it offers faster transmission of assignments than using traditional way by using online system. The interface use to invoke different testing program by teachers, So Save the time and cost for teachers by enabling them to put up a fast response for students as well as increasing the quality of the feedback provided to students.

Keywords: UML (Unified Modeling Language), Nant (Not Ant), OSS (online assignment Submission), Script file, DotNet2005.

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