Syftet med denna studie är att undersöka hur en miljöfrämjande mobilapplikation kan motivera användare till att agera mer miljövänligt genom persuasiva designprinciper. I denna studie föreslås en uppsättning designprinciper att ha i åtanke vid utveckling av övertygande mobilapplikationer som syftar till miljövänliga beteendeförändringar. Det utvärderades tre existerande miljöfrämjande mobilapplikationer med hjälp av PSD-modellens designprinciper, varav en valdes ut för användarundersökningen. Totalt sex personer deltog i studien och fick testa den valda mobilapplikationen under en veckas tid, i syfte att bekanta sig med applikationens funktioner. I samband med detta fick deltagarna besvara en enkät med allmänna frågor kring deras miljövänliga vanor. Den slutliga fasen inkluderade intervjun, som innehöll frågor gällande deltagarnas åsikter om funktioner och motivationsfaktorer för att använda miljöfrämjande applikationer. Resultatet visade att designprinciperna belöning, individualisering, simulering, självkontroll, normativt inflytande, samarbete, social jämförelse, konkurrens och påminnelser hade störst inflytande på användarnas motivation att använda applikationen och agera miljövänligt. De utvalda designprinciperna berodde huvudsakligen på individuella, sociala och praktiska faktorer. / This study aims to investigate how an environmental mobile application can motivate users to act more eco-friendly by using persuasive design principles. In this study, we identify a set of key principles to consider when designing mobile persuasive technology in order to motivate and influence pro-environmental behavior change. We evaluated three existing mobile applications by using PSD design principles. After the evaluation, one mobile application was selected for usertesting, with a total of six participants. The participants received one week to get familiar with the application and its functionalities . Furthermore, the participants received a survey with general questions about their eco-friendly habits. The upcoming phase included the interview we conducted, which contained questions to bring forward the participants opinions about functions and motivation factors that could affect their usage of eco-friendly applications. The result showed that the design principles rewards, personalization, simulation, self-monitoring, normative influence, cooperation, social comparison, competition and reminders had the greatest influence on the users motivation to use the application and act eco-friendly. The reason of importance for the chosen design principles was mainly due to individual, social and practical factors.

In this paper, we examine the persuasive design in e-commerce. This is an area with a strong representation of the design elements that can be classified as persuasive (Alhammand & Gulliver, 2014). Despite this, the spread of studies investigating persuasive design elements in e-commerce basically non-existent. We use the PSD model (Oinas-Kukkonen & Harjumaa, 2009) to identify the presence of persuasive design element on four e-commerce sites through quantitative mapping. The quantitative mapping allows us to carry out a qualitative study of the PSD model as a tool for the identification of these elements in the context of e-commerce sites. We could see that a majority of the design principles were found on the investigated e-commerce sites, the presence was highest among the design principles that is about the system's credibility, as well as those that guide the user to the intended target behavior. In the evaluation of PSD model, we identified direct dependencies between individual design principles and the need for user evaluations. We found some problems with interpreting the design principles to be applied to them in the context of e-commerce, which suggests that a clarification of designprincipera would be desirable. / I den här uppsatsen undersöker vi persuasive design inom e-handel. Detta är ett område som uppvisar en kraftig representation av design-element som kan klassificeras som persuasive (Alhammand & Gulliver, 2014). Trots detta så är utbredningen av studier som undersöker persuasive design-element inom e-handel i princip obefintlig. Vi använder oss av PSD-modellen (Oinas-Kukkonen & Harjumaa, 2009) för att identifiera förekomsten av persuasive design-element på fyra stycken e-handelsplatser genom en kvantitativ kartläggning. Den kvantitativa kartläggningen gör vi för att kunna genomföra en kvalitativ undersökning av PSD-modellen som verktyg för identifiering av dessa element i kontexten e-handelsplatser. Vi kunde se att en majoritet av designprinciperna återfanns på de undersökta e-handelsplatserna, förekomsten var högst hos de designprinciper som handlar om systemets kredibilitet samt de som guidar användaren till det tänkta målbeteendet. I utvärderingen av PSD-modellen identifierade vi direkta beroenden mellan enskilda designprinciper och ett behov av användarutvärderingar. Vi fann vissa problem med att tolka designprinciperna för att kunna appliceras dem på kontexten e-handelsplats, vilket talar för att ett förtydligande av designprincipera skulle kunna vara eftersträvansvärt.

Abstract Cognitive Radio (CR) improves the efficiency of spectrum utilization by allowing non- licensed users to utilize bands when not occupied by licensed users. In this thesis, we address several challenges currently limiting the wide use of cognitive radios. These challenges include identification of unoccupied bands, energy consumption and other technical challenges. Improved accuracy edge detection techniques are developed for CR to mitigate both noise and estimation error variance effects. Next, a reduced complexity Simplified DFT (SDFT) is proposed for use in CR. Then, a sub-Nyquist rate A to D converter is introduced to reduce energy consumption. Finally, a novel multi-resolution PSD estimation based on expectation-maximization algorithm is introduced that can obtain a more accurate PSD within a specified sensing time.

Master thesis is focused on the philosophy of design adaptive controller. In the theoretic part are described parts of the adaptive controller, which belongs parts as online identification by recursive least-squares method and PSD controller, which can set its parameters according to identified system (use Z-N method). The part of control system with transport delay is situated at the conclusion of the theoretic part, there are focused on Smith predictor. Practical part is focused on verification of all algorithms, which was performed on models and real systems.

Master thesis is focused on the philosophy of design adaptive controller. In the theoretic part are described parts of the adaptive controller, which belongs parts as online identification by recursive least-squares method and PSD controller, which can set its parameters according to identified system (use Z-N method). The part of control system with transport delay is situated at the conclusion of the theoretic part, there are focused on Smith predictor. Practical part is focused on verification of all algorithms, which was performed on models and real systems.

Les épines dendritiques sont de petites protrusions post-synaptiques présentant des changements morphologiques corrélés avec la plasticité synaptique. Elles ont pour origine les filopodes dendritiques qui s’élargissent lors du contact avec l’axone. Ces changements morphologiques impliquent une grande variété de molécules dont des protéines associées à l’actine et des protéines d’adhésion. Cependant, comment ces différentes protéines sont coordonnées dans le temps et l’espace est encore largement méconnu. De plus, les techniques de microscopie conventionnelle ne permettent pas d’étudier l’organisation et la dynamique de ces protéines dans les épines dont la taille est proche de la limite de resolution. L’objectif de ma thèse a donc été d’explorer le rôle des protéines associées à l’actine ainsi que celui des protéines d’adhésion N-cadhérines dans l’organisation et la dynamique du cytosquelette d’actine des épines dendritiques. Dans une première étude, nous avons suivi la motilité des filopodes et épines dendritiques de neurones en visualisant l’actine-GFP. Nous avons couplé cette approche avec : 1) une technique de piégeage optique de microsphères recouvertes de N-cadhérines ou des substrats micro-imprimés également recouverts de N-cadhérines afin de contrôler temporellement et spatialement les adhésions cadhérine-cadhérine, 2) la stimulation pharmacologique de la myosine II afin d’induire la contraction F-actine/myosine et 3) l’expression de mutants de N-cadhérine non adhésifs. Nous avons ainsi démontré que la stabilisation des filopodes en épines était dépendante de l’engagement d’un embrayage moléculaire entre les adhésions trans-synaptiques N-cadhérine et le flux rétrograde d’actine généré par les myosines II. Dans une deuxième étude, nous avons utilisé la microscopie super-résolutive (PALM et dSTORM) et le suivi de protéines individuelles (sptPALM) pour étudier l’organisation et la dynamique à l’échelle nanométrique des protéines à l’origine des réseaux d’actine branchés dans les épines. Ainsi, nous avons caractérisé la localisation et la dynamique de l’actine, du complexe Arp2/3, du complexe WAVE, d’IRSp53, de VASP et de Rac-1. Nous avons montré que, contrairement aux structures motiles classiques comme lamellipode, le réseau d’actine branché dans les épines n’ést pas formé aux extrémités protrusives puis incorporé dans un flux rétrograde d’actine. Ce réseau est initié à la PSD puis croît vers l’extérieur afin de générer les protrusions membranaires responsablent des changements morphologiques de l’épine. Nos résultats montrent également qu’un contrôle strict de l’activité de Rac-1 est nécessaire au maintien de la morphologie des épines dendritiques et de l’architecture du réseau d’actine branché. L’ensemble de mon travail souligne l’importance du rôle de l’organisation à l’échelle nanométrique du réseau d’actine branché et des adhésions N-cadhérine dans la dynamique et la formation des épines dendritiques. Ces résultats pourraient avoir un rôle important dans la compréhension des changements morphologiques lors de la plasticité synaptique. / Dendritic spines are tiny post-synaptic protrusions exhibiting changes in morphology correlated with synaptic plasticity. They originate from motile dendritic filopodia, which enlarge after contacting axons. These morphological changes involve a wide number of molecular actors, including actin-binding proteins, and adhesion molecules. However, how these various molecular components are coordinated temporally and spatially to tune changes in spine shape remains unclear. Furthermore, conventional photonic microscopy techniques could not achieved the spatial resolution required to study the dynamic nanoscale organization of these proteins within the micron size dendritic spines. The objective of my Ph.D. was to unravel how actin-binding proteins and N-cadherin adhesion regulate the organization and dynamics of F-actin network in dendritic spines. In a first study, we measured the motility of dendritic filopodia and spines by time lapse imaging of actin-GFP in primary hippocampal neurons. We combined those measurements with: 1) manipulation of N-cadherin coated beads with optical tweezers, or micropatterns to control the timing and location of nascent N-cadherin adhesions, 2) pharmacological stimulation of myosin II to trigger contraction of the F-actin/myosin network and 3) expression of non-adhesive N-cadherin mutants to compete for the interaction between N-cadherin adhesion and F-actin. Using these different approaches we demonstrated that the stabilization of dendritic filopodia into mature spines was dependent on the engagement of a molecular clutch between trans-synaptic N-cadherin adhesions and the myosin driven F-actin flow. In a second study, we used super resolution microscopy (PALM and dSTORM) and single protein tracking (sptPALM) to study the dynamic nanoscale organizations of branched actin networks within dendritic spines. Using these technics, we characterized within dendritic spines, the localization and dynamics of actin, Arp2/3 complex, WAVE complex, IRSp53, VASP and Rac-1. We established that, opposite to classical motile structures such as the lamellipodium, branched F-actin networks in dendritic spines are not formed at the tip of membrane protrusions and incorporated in a retrograde flow. On the contrary, they are growing outwards from the PSD generating membrane protrusions responsible for spine motility. We also show that a thigh control of Rac1 activity is required to maintain dendritic spine morphology and branched actin network organization. Altogether, these studies point out the role of the nanoscale functional organization of F-actin networks and its linkage to adhesion proteins in the regulation of dendritic spine formation and dynamics. These findings may have important implications in the understanding of spine morphology changes driven by synaptic activity.

Studien undersöker hur övertygande design används på sociala medietjänsten Instagram samt hur användarna upplever det. En kartläggning av beståndsdelar har genomförts för att identifiera appliceringen av övertygande designtekniker som ämnar till attityd- eller beteendeförändringar. Sociala medier har idag fått en betydande del i människors vardagliga liv och påverkar människan på en mängd olika sätt, det är få saker som tyder på att användandet kommer att minska framöver då det ständigt utvecklas nya plattformar. En heuristisk utvärdering med PSD-modellen som grund genomfördes för att identifiera användandet av övertygande design inom Instagrams gränssnitt. För att undersöka användarnas upplevelser genomfördes semistrukturerade intervjuer. Resultatet visade att övertygande design gick att finna i tjänstens gränssnitt genom bland annat notifikationer samt anpassat hemflöde. Studien visar även att användarnas upplevelse av övertygande design på Instagram varierar och att det till största del inte var någonting som de själva noterade i användandet. Resultatet visar att det till övervägande del var negativa upplevelser även fast vissa positiva aspekter presenterades. Framför allt upplevde användarna att de tappade kontroll över användandet av tjänsten där de upplevde att det var onödig spenderad tid som kunde utnyttjas bättre på andra vis. Vidare upplevdes notifikationer som särskilt störande där det hade en negativ påverkan på upplevelsen. En framhävande positiv upplevelse var det skräddarsydda innehållet som anpassade sig efter användarens intressen och behov vilket bidrog till relevant presenterad information. Studiens frågeställning är besvarad då resultatet tydligt visar hur övertygande designtekniker används på Instagram samt ger insikt i användarnas upplevelser av övertygande design på Instagram. / This study examines how persuasive design is used within the social media service Instagram and how the users experience this. Instagrams interface and components have been mapped out, in order to identify the use of persuasive design techniques with the intent to change the behavior or attitude of the users. Today, social media has an impact on people's everyday lives and affects us in a variety of ways. There are few indications pointing towards a decrease in the use of social media in the future, as it is constantly evolving as new platforms are created. A heuristic evaluation has been performed, with the PSD model as the set of guidelines. This was done in order to identify persuasive design techniques within the interface of Instagram. To investigate the experiences of the users, semi-structured interviews were conducted. The results showed that persuasive design could be found throughout the platform, for example through the use of notifications and the adaptive home feed. Results also showed that the users' experiences varied and for the most part it was not something that they themselves noted during their use. The results show that it was predominantly negative experiences even though some positive aspects were presented. The users felt a loss of control over their use of the platform as they felt that unnecessary time was spent on the application that could be better utilized elsewhere. Furthermore, notifications were perceived as a disturbance and therefore had a negative impact on their experience. A particularly positive experience was the tailored content that adapted to the user's interests and needs, which contributed to the presented information being relevant. The problem statement is answered as the results clearly show how persuasive design is used on Instagram and provide insight into the users experiences of it.

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / Feher Keying (FK) signals are clock shaped baseband waveforms with the potential to attain very high spectral efficiencies. Two FK signals which have different level rectangular waveforms (named as FK-1) or sinusoidal waveforms (named as FK-2) for two binary symbols are considered in this paper. These signals have periodic components in the time domain. Therefore they have cyclostationary properties. This means that spectral correlation exists in the frequency domain. For each type of waveforms, spectral correlation has been investigated. FK signals can be expressed mathematically into two parts in the frequency domain – discrete part and continuous part. The discrete part has one or more discrete impulse(s) in their spectra and the continuous part has periodically the same shape of harmonics in their spectra. The correlations of their spectra have been obtained mathematically and by simulation. It is shown that FK signals have high correlation related to the symbol rate. Finally, some suggestions how these properties can be used to improve their performance by devising better demodulators are discussed. These properties can be used for interference rejection at the receiver, which results in low bit error rate performance.

International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Performances of a subclass of a new spectral efficient modulation scheme, designated as Feher Keying [1], or FK, is evaluated. The Power Spectral Density (PSD) and Bit Error Rate (BER) characteristics of FK are presented. FK has ultra high spectral efficiency and satisfies the frequency mask for WLAN defined in FCC part 15, and it has a simple structure for high bit rate implementation.

Multiphase flows occurring in pipelines with a serpentine configuration is an important phenomenon, which can be encountered in heat exchangers used in a variety of industrial processes. More specifically, in many industrial units such as a large cracking furnace in a refinery, the tubes are arranged in a serpentine manner and are relatively short. As flow negotiates round the 180o bend at the ends of the tubes, the generated centrifugal force could cause flow maldistribution creating local dry spots, where no steady liquid film is formed on the adjacent straight sections of the pipe. As a result, events including coking, cracking and overheating of heat transfer surfaces may occur and lead to frequent shutdown of the facilities. Consequently, this could increase operating costs and reduce production revenue. Thus, it is desirable to know the effect that the bends exert on the flow in the straight part of the pipe. Apart from this, knowledge of the bend effects on the flows in the pipeline could also be important for the design of other pipelines for gas/liquid transport, e.g. offshore gas and oil pipelines. Quite a large number of studies have been found in the literature. The majority of them were for two-phase flow with small diameter pipes (i.d. ≤ 50 mm). However, studies with large diameter pipes (i.d. ≥ 100 mm), have increasingly been considered in recent years as problems related to large diameter vertical pipes are being encountered more and more often in industrial situations. This thesis studies the effect of 180o bends on the characteristics and development of gas-liquid two-phase flows in large diameter downward and upward pipes. The study particularly focuses on the influence of serpentine configuration on flow structure, cross-sectional void distribution and circumferential liquid film profiles and their development along the downward and upward sections. It was found that both the top and bottom bends have considerable impacts on flow behaviour, although to varying degrees. These impacts were highly dependent on the air and water flow rates. For sufficient flow rates, the bends were observed to create flow maldistribution in the adjacent straight section, due to the effects of centrifugal force. The air moved towards the inner zone of the bend and the water towards the outer zone, while a lesser quantity of water was identified on the other surfaces of the pipe. Investigation of the film thickness development in the downward and upward sections showed that, the liquid film behaviour close to the bends was significantly different from those located further away. This can be attributed to the centrifugal force of the bends. Examination of the power spectral density (PSD) along the downward and upward sections showed that, the shape of PSD located in the adjacent section to the bends, was substantially different from those located further away. Furthermore, several flow regime maps were generated which showed that, in addition to bubbly, intermittent and annular flows, unstable flows existed along the upward section, particularly for low gas and water flow rates. In this study it was found that, the lower bend was periodically blocked by the liquid and then blown through by the accumulated air. The data obtained from this study were compared with different theoretical correlations found in the existing literature. Some discrepancy between the results of the current study and those of previous published materials was noted. Updated correlations were presented which provided well results when they applied for the data obtained from the current study and previous studies.