| 1. |
- Abidin, Aysajan
(författare)
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Weaknesses of Authentication in Quantum Cryptography and Strongly Universal Hash Functions
- 2010
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Authentication is an indispensable part of Quantum Cryptography, which is an unconditionally secure key distribution technique based on the laws of nature. Without proper authentication, Quantum Cryptography is vulnerable to “man-in-the-middle” attacks. Therefore, to guarantee unconditional security of any Quantum Cryptographic protocols, the authentication used must also be unconditionally secure. The standard in Quantum Cryptography is to use theWegman-Carter authentication, which is unconditionally secure and is based on the idea of universal hashing.In this thesis, we first investigate properties of a Strongly Universal hash function family to facilitate understanding the properties of (classical) authentication used in Quantum Cryptography. Then, we study vulnerabilities of a recently proposed authentication protocol intended to rule out a "man-in-the-middle" attack on Quantum Cryptography. Here, we point out that the proposed authentication primitive is not secure when used in a generic Quantum Cryptographic protocol. Lastly, we estimate the lifetime of authentication using encrypted tags when the encryption key is partially known. Under simplifying assumptions, we derive that the lifetime is linearly dependent on the length of the authentication key. Experimental results that support the theoretical results are also presented.
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| 2. |
- Aijaz, Asim
(författare)
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HiPIMS-based Novel Deposition Processes for Thin Films
- 2012
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this research, high power impulse magnetron sputtering (HiPIMS) based new deposition processes are introduced to address; the issue of low degree of ionization of C in magnetron sputtering discharges, and the difficulty encountered in thin film deposition on complex-shaped surfaces. The issue of low degree of C ionization is addressed by introducing a new strategy which is based on promoting the electron impact ionization ofC by increasing the electron temperature in the plasma discharge using Ne, instead of conventionally used Ar. The Ne-based HiPIMS process provides highly ionized C fluxes which are essential for the synthesis of high-density and sp3 rich amorphous carbon (a-C) thin films such as diamond-like carbon (DLC) and tetrahedral a-C (ta-C). The feasibility of coating complex-shaped surfaces is demonstrated by using the dual-magnetron approach in an open-field (magnetic field of the magnetrons) configuration and performing sideways deposition of Ti films. The HiPIMS-based open-field configuration process enhances the sideways transport of the sputtered flux — an effect which is observed in the case of HiPIMS.The characterization of the Ne-HiPIMS discharge using a Langmuir probe and mass spectrometry shows that it provides an increase in the electron temperature resulting in an order of magnitude decrease in the mean ionization length of the sputtered C as compared to the conventional Ar-HiPIMS discharge. The C1+ ion energy distribution functions exhibit the presence of an energetic C1+ ion population and a substantial increase in the total C1+ ion flux. The higher C1+ ion flux facilitates the growth of sp3 rich carbon films with mass densities, measured by x-ray reflectometry, reaching as high as approx. 2.8 gcm-3.The dual-magnetron open-field configuration process is operated in DCMS as well as in HiPIMS modes. The plasma characterization, performed by Langmuir probe measurements and optical emission spectroscopy, shows that the plasma density in the Ti-HiPIMS discharge is higher than that of the Ti-DCMS discharge. This results in the higher ionized fraction of the sputtered Ti in the case of HiPIMS. The film uniformity and the deposition rate of the film growth, obtained by employing scanning electron microscopy, demonstrate that the sideways deposition approach can be used for depositing thin films on complex-shaped surfaces.
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| 3. |
- Andersson, Ann-Christine
(författare)
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Practice-based Improvements in Healthcare
- 2010
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A central problem for the healthcare sector today is how to manage change and improvements. In recent decades the county councils in Sweden have started various improvement initiatives and programs in order to improve their healthcare services. The improvement program of the Kalmar county council, which constitutes the empirical context for this thesis, is one of those initiatives.The purpose of this thesis is to contribute to a broader understanding of large-scale improvement program in a healthcare setting. This is done by analyzing practitioner’s improvement ideas, describing participants in the improvement projects, revising and testing a survey to measure the development of improvement ideas and describing the improvement program from a theoretical perspective. The theoretical change model used looks at change from two opposing directions in six dimensions; Goals, Leadership, Focus, Process, Reward system and Use of consultants.The aims of the county council improvement program are to become a learning organization, disseminate improvement methodologies and implement continuous quality improvements in the organization. All healthcare administrations and departments in the county council were invited to apply for funds to accomplish improvement projects. Another initiative invited staff teams to work with improvement ideas in a program with support from facilitators, using the breakthrough methodology. Now almost all ongoing developments, improvements, patient safety projects, manager and leader development initiatives are put together under the county council improvement program umbrella.In the appended papers both qualitative and quantitative research approach were used. The first study (paper I) analyzed which types of improvement projects practitioners are engaged in using qualitative content analysis. Five main categories were identified: Organizational Process; Evidence and Quality; Competence Development; Process Technology; and Proactive Patient Work. Most common was a focus on organizational changes and process, while least frequent was proactive patient work. Besides these areas of focus, almost all aimed to increase patient safety and increase effectiveness and availability.Paper II described the participants in two of the initiatives, the categorized improvement projects in paper I and the team members in the methodology guided improvement programs. Strong professions like physicians and nurses were well represented, but other staff groups were not as active. Managers were responsible for a majority of the projects. The gender perspective reflected the overall mix of employees in the county council.Paper III described a revision and test of a Minnesota Innovation Survey (MIS) that will be used to follow and measure how quality improvement ideas develop and improve over time. Descriptive statistics were presented. The respondents were satisfied with their work and what they had accomplished. The most common comment was about time, not having enough time to work with the improvement idea and the difficulty of finding time because of regular tasks. This was the first test of the revised survey and the high use of the answer alternative “Do not know” showed that the survey did not fit the context very well in its present version.Trying to connect the county council improvement program and the initiatives studied in papers I and II with the change model gave rise to some considerations. The county council improvement program has an effort to combine organizational changes and a culture that encourages continuous improvements. Top-down and bottom-up management approaches are used, through setting out strategies from above and at the same time encouraging practitioners to improve their day-to-day work. Whether this will be a successful way to implement and achieve a continuous improvement culture in the whole organization is one of the main issues remaining to find out in further studies.
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| 4. |
- Andersson, Annelie, 1971-
(författare)
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Maternal behaviour, infanticide and welfare in enclosed European wild boars (Sus scrofa)
- 2010
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- European wild boars (Sus scrofa) are kept in Swedish enclosures for hunting and meat production purposes. The sows are known to undergo behavioural changes in connection with farrowing and their natural behaviours may be compromised by the limited area of the enclosure. The general aim of this thesis was to provide detailed quantitative data on wild boar sows when farrowing in captivity and to report whether possible needs can be compromised by the limitations of an enclosure. Specifically, it was aimed to provide a quantitative and functional account of the occurrence of infanticide, and its possible relations to welfare of confined wild boars.A field study was carried out in a hunting enclosure, where 1200 hours of behavioural recordings and data from 22 farrowings were collected. The farrowing period could be divided into three phases: pre-farrowing, isolation and sociality phases (in relation to farrowing: day -14 to -1, day 1 to 8, day 9 to 14 respectively). The activity decreased during isolation and increased in the sociality phase. The average distance to other individuals increased during isolation and decreased in the sociality phase. Habitat use changed towards more protective habitats after farrowing (Paper I).Non-maternal infanticide was documented in 14 out of 22 litters. Infanticide, typically performed by an older and larger sow than the mother, caused the deaths of all neonates in all but one affected litters. We found no effect of relatedness. A questionnaire sent to 112 owners of enclosures in Sweden and Finland resulted in 62 responses. Although the owners were often not able to provide exact figures on reproduction and mortality, nonmaternal infanticide was reported to be the most common cause of piglet mortality. The occurrence of infanticide was unrelated to size of enclosure and to variations in husbandry routines. All together results may suggest that non-maternal infanticide is part of the normal behavioural repertoire in wild boars (Paper II).The studies of this thesis reveals the farrowing period as the most dynamic and perhaps most challenging for wild boar sows in enclosures. There are serious welfare concerns in the husbandry of wild boars in Swedish enclosures. The most obvious welfare problem is non-maternal infanticide, where both sows and piglets are assumed to suffer, and where the outcome from the action must be considered unacceptable. If wild boar husbandry shall be equated with other animal husbandry in our society, it needs to be regulated to overcome many of the presented potential welfare problems in this thesis.
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| 5. |
- Andersson, Dennis, 1980-
(författare)
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Mission Experience : How to Model and Capture it to Enable Vicarious Learning
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Organizations for humanitarian assistance, disaster response and military activities are characterized by their special role in society to resolve time-constrained and potentially life-threatening situations. The tactical missions that these organizations conduct regularly are significantly dynamic in character, and sometimes impossible to fully comprehend and predict. In these situations, when control becomes opportunistic, the organizations are forced to rely on the collective experience of their personnel to respond effectively to the unfolding threats. Generating such experience through traditional means of training, exercising and apprenticeship, is expensive, time-consuming, and difficult to manage.This thesis explores how and why mission experience should be utilized in emergency management and military organizations to improve performance. A multimedia approach for capturing mission experience has further been tested in two case studies to determine how the commanders’ experiences can be externalized to enable vicarious learning. These studies propose a set of technical, methodological, and ethical issues that need to be considered when externalizing mission experience, based on two aforementioned case studies complemented by a literature review. The presented outcomes are (1) a model aligning abilities that tactical organizations need when responding to dynamic situations of different familiarity, (2) a review of the usefulness of several different data sources for externalization of commanders’ experiences from tactical operations, and (3) a review of methodological, technical, and ethical issues to consider when externalizing tactical military and emergency management operations. The results presented in this thesis indicate that multimedia approaches for capturing mission histories can indeed complement training and exercising as a method for generating valuable experience from tactical missions.
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| 6. |
- Andersson, Eva
(författare)
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Hörselscreening av en population med utvecklingsstörning : Utvärdering av psykoakustisk testmetod och av OAE-registrering som komplementär metod
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Populationer med utvecklingsstörning behöver kontinuerlig hörseltestning, men konsensus om lämplig testmetod saknas.Syfte: Syftet med Studie I var att utvärdera psykoakustisk testmetod och med Studie II att utvärdera OAE-registrering som komplementär metod.Studie I. 1478 barn och vuxna med lätt till djup utvecklingsstörning, i åldrarna 7-91 år deltog i studien. De testades med tonaudiometri på sex frekvenser på screeningnivån 20 dB HL med lätt modifierad testutrustning. Kriterierna för remittering var tröskelnivåer på ≥ 25 dB HL på två frekvenser eller flera på ett öra eller båda. 1470 (99,5%) barn och vuxna medverkade i screeningen och 1325 (90%) testades på båda öronen på samtliga sex frekvenser. En majoritet, 987 (67,1%), medverkade i vanlig tonaudiometri, 234 (15,9%) i lekaudiometri, och 249 (16,9%) testades med observationsaudiometri. 669 (45%) visade normala värden medan 809 (55%) visade onormala värden relaterat till screeningkriterierna. Av de 809 accepterade 441 (54,5%) remittering för hörselutredning.Studie II. 38 vuxna med måttlig till djup utvecklingsstörning, i åldrarna 31-73 år deltog i studien, alla med ofullständiga testresultat vid tonaudiometri. Portabel utrustning, ILO 288 Echoport och dator Compaq LTE 5100 med mjukvara ILO 88 V 4.2, användes. Otoskopi och tympanometri kompletterade registreringen. Kriterierna för emissioner var S/N 3 dB eller mer och reproducerbarhet på 60% eller mer på åtminstone tre frekvensband. Kriterierna för partiella emissioner var desamma men för en eller två frekvenser. Två personer behövdes för att genomföra testningen: en för att hålla testpersonen lugn och tyst och den andra för att sköta testapparaturen. Reproducerbara TEOAE-svar registrerades från 11 öron (7 personer), partiella svar från 6 öron (4 personer), inga emissioner kunde registreras från 15 öron (10 personer) och 4 öron (4 personer) med otit eller vaxpropp testades inte. Registreringen från 24 öron (13 personer) kunde inte värderas p g a alltför mycket yttre och inre störningar. 8 personer vägrade delta i testningen. Endast 4 personer visade emissioner på båda öronen. Resultatet av undersökningen blev att 34 personer (89.5%) behövde testas om eller bli remitterade för ytterligare utredning, 21 av dem (55%) beroende på störningar vid registreringen eller p g a vägran att medverka.Konklusion: Tonaudiometri med lätt modifiering kan användas för screening av en population med lätt till djup utvecklingsstörning. TEOAE-registrering, som den genomfördes, kan inte uppfylla kraven på en fungerande testmetod för en population med måttlig till djup utvecklingsstörning. I det enskilda fallet kan TEOAE-registrering vara ett komplement till andra hörseltest. Det mest utmanande och tidskrävande är att introducera testprocedurerna på ett sätt som begränsar oro och skapar tillit. Oberoende av testmetod är en audionom med tålamod och vana att samarbeta med personer med utvecklingsstörning en viktig förutsättning för framgångsrik och säker testning.
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| 7. |
- Andréasson, Ester
(författare)
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”Det är väldigt mycket datoriserat är det.” – En studie om IT-utveckling i ett landsting: policy, implementering och praktik
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Den ökade användningen av informationsteknik (IT) är en av flera förändringsprocesser i den offentliga sektorn idag. Användningen är nära kopplad till positiva föreställningar om de möjligheter IT-användningen ger för att kunna modernisera och effektivisera verksamhet. I de offentliga organisationerna råder ofta en starkt teknikpositiv diskurs. IT-utveckling ses som viktig och nödvändig och sker många gånger relativt politiskt oreflekterat.I de processer som äger rum när nya IT-system upphandlas och implementeras i offentliga organisationer samlas flera olika slag av aktörer, såväl offentliga som privata. I denna licentiatuppsats undersöks vilka aktörer som har makt i dessa förändringsprocesser kopplade till IT i den offentliga sektorn.Mer precist sker denna undersökning genom en fallstudie i ett svenskt landsting, där processerna kring införandet av ett nytt vårdinformationssystem har studerats. Studierna har skett genom dokumentstudier, observationer av olika slag samt flertalet intervjuer med tjänstemän och vårdpersonal. De empiriska resultaten analyseras i uppsatsen med hjälp av teorier kring policy, implementering samt teknik och organisation.Licentiatuppsatsen bidrar till forskningen om e-förvaltning såväl empiriskt som teoretiskt. Dess viktigaste empiriska bidrag är två. För det första har införandet av nya IT-system omfattande betydelse för organisering i offentliga organisationer. För det andra indikerar uppsatsens resultat att införandet av ny teknik i offentliga organisationer kan bidra till att sudda ut gränsen mellan det offentliga och det privata. Uppsatsens teoretiska bidrag sammanfattas i den analysmodell som presenteras, och som ger möjlighet att betrakta och analysera policy-, implementerings- och praktikprocesser rörande IT-utveckling i offentliga organisationer som integrerade sådana.
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| 8. |
- Appelkvist, Jenny
(författare)
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Det självklara företagandet? : Kvinnors företagande i veterinärprofessionen
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Veterinärsektorn har under de två senaste åren fångat riskkapitalbolagens uppmärksamhet som en sektor som är både växande och lönsam. Lönsamheten är kopplad till bland annat den förändrade djurhållningen i Sverige; med en minskning av lantbruksdjur och ökning av sällskapsdjur i kombination med att djurägarna är beredda att lägga allt mer pengar på sina djurs välbefinnande. Den svenska veterinärprofessionen har även feminiserats numeriskt parallellt med djurhållningens förändring. I en tid då företagande och särskilt kvinnors företagande ses som en viktig resurs för, och grund till, den svenska välfärden blir det relevant att problematisera förutsättningarna för kvinnors företagande i veterinärprofessionen.Föreliggande studie har varit explorativ och insamling av information och empiri har skett i tre steg. Det första steget, som benämns som kontext- och litteraturstudie syftade till att samla in information om den svenska veterinärsektorn i stort. I detta steg gjordes även en genomgång av relevant forskningslitteratur, något som gjorts löpande under studiens gång. I det andra steget gjordes en kartläggning av veterinärsektorn i Östergötlands län och i det tredje steget genomfördes en intervjustudien med samtliga kvinnor tillika företagande veterinärer i Östergötland (totalt 10). Teoretiska utgångspunkter tas i entreprenörskaps- och småföretagsforskning i kombination med professions- och genusforskning. Teori om Push och Pull för företagsstart sätts i samband med professionskaraktäristika utifrån ett perspektiv av könssegregering och könskodning.Resultatet visar att företagandet i den svenska veterinärprofessionen kan ses som självklart. Detta då rörelsen in och ut ur företagande ses som oproblematiskt. Analysen av hinder och möjligheter för företagandet emanerar i tre dilemman där kund ställs mot patient, kollega mot konkurrent och etik mot lönsamhet. Bidrag görs till teorin om Push och Pull men även professionsteori där uppdelningen av professioner i olika professionstyper problematiseras. Studien indikerar även en förändring i genussystemet och har därmed implikationer för alla tre teoretiska områden.
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| 9. |
- Arwinge, Olof, 1971-
(författare)
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Internal Control : A Study of the Concept and Themes of Internal Control
- 2010
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis studies the accounting and auditing approach to control where the concept of internal control has developed along with the theory and practice of accounting and auditing and its stated objectives. In this context, internal control has traditionally been regarded as a means of ensuring financial reporting quality as well as a way of preventing and detecting fraudulent activity.We have surveyed scientific research on the subject of internal control and reviewed regulatory texts as well as practical frameworks and standards. Based on this literature study, we have investigated some of the findings from previous research. Components and particular features of internal control were described and discussed. We have also identified and summarized themes and issues that frequently occur in writings on the subject.During recent years, demands have been made for greater accountability and transparency in corporate governance. The independent audit activity has become the primary tool for securing accountability. Some regard this as the emergence of an audit society. An important joint development has been the rise of internal control systems. Internal control, once a private matter for technical assurance specialists, has risen to be an autonomous field of expertise and a mode of organizing uncertainty. Traditionally internal control has had a fairly direct relationship to the accounting records. The wider approaches to internal control have expanded its boundaries significantly, far beyond the financial reports and the duties of the accountant. Internal control has become an all-encompassing process.Enterprise risk management practices are growing and evolving. An associated development has been that internal control has become more closely tied to these risk management practices, and therefore also to the formulation and execution of strategies. New risk-related regulations and practical frameworks have contributed to the transformation of internal control into a co-extensive with risk management. Internal control is now considered to be a form of risk treatment through which risk may be managed in different ways.Internal control is today a primary regulatory and formal olicy object. Lawmakers and supervisory authorities are increasingly concerned with the design and operating effectiveness of internal controls. Disclosure requirements imposed on firms are forcing them to provide public disclosures about their internal control systems, which were previously private to firms.Both scientific research and practical writings suggest that internal control designs are contingent upon certain variables. These variables include company objectives and strategies, regulatory characteristics, risk and risk appetite, firm size and managements’ attitudes to risk and control. Building internal control capabilities is important if firms are to be able to design balanced, integrated, dynamic and cost-effective internal controls.Internal control is considered to be a key corporate governance mechanism. Some researchers however, have pointed out that there is still much to learn about internal control quality and how internal control is associated with corporate governance quality. The fact that internal control is an inherently complex concept poses a significant research barrier, and while all research methods are valid, it is unlikely that archival studies or experiments are able to measure internal control quality. Instead, we recommend case studies of how firms design, apply and oversee their systems of internal control.This study was made possible through the research collaboration between my former employer, Skandia, and Linköping University through the Research Programme for Auditors and Consultants. During the final stage, generous funding was provided by the Jan Wallanders and Tom Hedelius foundation as well as the Tore Browaldhs foundation.
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| 10. |
- Axelsson, Patrik, 1985-
(författare)
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On Sensor Fusion Applied to Industrial Manipulators
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- One of the main tasks for an industrial robot is to move the end-effector in a predefined path with a specified velocity and acceleration. Different applications have different requirements of the performance. For some applications it is essential that the tracking error is extremely low, whereas other applications require a time optimal tracking. Independent of the application, the controller is a crucial part of the robot system. The most common controller configuration uses only measurements of the motor angular positions and velocities, instead of the position and velocity of the end-effector.The development of new cost optimised robots have introduced unwanted flexibilities in the joints and the links. It is no longer possible to get the desired performance and robustness by only measuring the motor angular positions. This thesis investigates if it is possible to estimate the end-effector position when an accelerometer is mounted at the end-effector. The main focus is to investigate Bayesian estimation methods for state estimation, here represented by the extended Kalman filter (EKF) and the particle filter (PF).A simulation study is performed on a two degrees of freedom industrial robot model using an EKF. The study emphasises three important problems to take care of in order to get a good performance. The first one is related to model errors which in general requires better identification methods. The second problem is about tuning of the EKF, i.e., the choice of covariance matrices for the measurement and process noise. It is desirable to have an automatic tuning procedure which minimises the estimation error and is robust to initial conditions of the tuned parameters. A variant of the expectation maximisation (EM) algorithm is proposed for estimation of the process noise covariance matrix Q. The EM algorithm iteratively estimates the unobserved state sequence and the matrix Q based on the observations of the process, where the extended Kalman smoother (EKS) is the instrument to find the unobserved state sequence.The third problem considers the orientation and position of the accelerometer mounted to the end-effector. A novel method to find the orientation and position of the triaxial accelerometer is proposed and evaluated on experimental data. The method consists of two consecutive steps, where the first is to estimate the orientation of the sensor from static experiments. In the second step the sensor position relative to the robot base is identified using sensor readings when the sensor moves in a circular path and where the sensor orientation is kept constant in a path fixed coordinate system.Finally, experimental evaluations are performed on an ABB IRB4600 robot. Different observers using the EKF, EKS and PF with different estimation models are proposed. The estimated paths are compared to the true path measured by a laser tracking system. There is no significant difference in performance between the six observers. Instead, execution time, model complexities and implementation issues have to be considered when choosing the method.
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