Informationsöverbelastning blir alltmer vanligare i den ständigt uppkopplade värld vi män- niskor lever i. Smarttelefonen skickar hela tiden ut notiser och information när någonting nytt sker till sina användare och den här utveckling har bidragit till att människor distraheras från viktiga livshändelser och effekterna kan resultera i tappat fokus, stress, depression och ut- brändhet. Syftet med det här kandidatarbetet är att skapa en designmetod som kan reducera informa- tionsöverbelastning. Vi har skapat en prototyp för ett socialt nätverk där användarna kan filtr- era innehållet i det sociala nätverket genom en filterfunktion. Användarna kan skapa nya fil- ter, aktivera samt avaktivera och byta mellan de skapade filtren för att stänga ute information som inte är relevant för stunden. Genom vår gestaltning undersöker vi om informationsöver- belastningen går att reducera genom kontextmedvetna system i mobilapplikationer där sys- temet känner av din kontext och därefter kan filtrera bort irrelevant information som du inte behöver ta del av just nu. Vi påpekar även säkerheten i sådana system och hur det kan kränka din integritet. / Information overload is becoming more common in the constantly connected world in which people live in. The smartphone constantly sends notifications and information to its users when something new happens, and this development has contributed to distracting people from vital life events, and the effects can result in lost focus, stress, depression and getting burned out. The main purpose of this Bachelor thesis is to create a design method that can reduce infor- mation overload. We have created a social network prototype where users can filter the con- tents of the social network through a filter function. Users can create new filters, enable and disable filters which then enables the user to filter out information that is not vital at the mo- ment. Through our prototype we examine whether information overload can be reduced through context aware systems in mobile applications, where the system recognizes your con- text and can filter out none vital information that you do not need to access at the moment. We also point out the security of such systems and how it may violate the users privacy.

In military battlefield domain, decision making plays a very important part because safety and protection depends upon the accurate decisions made by the commanders in complex situations. In military and defense applications, there is a need of such technology that helps leaders to take good decisions in the critical situations with information overload. With the help of multi-sensor information fusion, the amount of information can be reduced as well as uncertainties in the information in the decision making of identifying and tracking targets in the military area.   Information fusion refers to the process of getting information from different sources and fusing this information, to supply an enhanced decision support. Decision making is the very core and a vital part in the field of information fusion and better decisions can be obtained by understanding how situation awareness can be enhanced. Situation awareness is about understanding the elements of the situation i.e. circumstances of the surrounding environment, their relations and their future impacts, for better decision making. Efficient situation awareness can be achieved with the effective use of the sensors. Sensors play a very useful role in the multi-sensor fusion technology to collect the data about, for instance, the enemy regarding their movements across the border and finding relationships between different objects in the battlefield that helps the decision makers to enhance situation awareness.   The purpose of this thesis is to understand and analyze the critical issue of uncertainties that results information in overload in military battlefield domain and benefits of using multi-sensor information fusion technology to reduce uncertainties by comparing uncertainty management methods of Bayesian and Dempster Shafer theories to enhance decision making and situation awareness for identifying the targets in battlefield domain.

Augmented Reality, eller förstärkt verklighet som det heter på svenska, är en teknologi som funnits i någon form sedan mer än 30 år tillbaka. Förstärkt verklighet system bygger och lägger virtuella objekt på vår syn av verkligheten, antingen genom video eller en genomskinlig display. Trots sin långa historia har det bara nyligen kunnat börja utvecklas i någon betydande mening, därför att den är starkt begränsad av processor- och display-teknik. Förutom tekniska begränsningar möter den också begränsningar i form av användarens kapacitet att bearbeta information som ett system matar ut. Om mängden information överskrider kapaciteten blir användaren överbelastad, ett tillstånd som kallas för Information Overload, vilket resulterar i att användaren får svårt att ta in och begripa information. Detta kan åthjälpas genom att utöva god design av användargränssnittet, som är en viktig del i alla system. Militären är mycket intresserade i teknologin i hopp om att det ska ge dem en bättre överblick på slagfältet. Den miljö som råder på ett slagfält kan dock vara mycket stressande, vilket ökar risken för Information Overload och gör det till en större utmaning att designa ett användbart system. Denna uppsats syftar att samla information om förstärkt verklighet, Informaion Overload och gränssnittsdesign på ett ställe och applicera det på ett militärt projekt, för att undersöka vilka utmaningar som uppstår när man designar för militärt bruk, utifrån traditionella riktlinjer och principer.

Les réseaux actuels et la prochaine génération des réseaux sans fil cellulaires (5G) doivent garantir, non seulement, les communications entre les gens (aussi connu sous le nom d'humain à humain - H2H), mais aussi à un déploiement massif de communication de type machine (MTC). MTC, ou encore Machine à Machine (M2M), peut être considérée comme des appareils qui peuvent établir des communications avec d’autres appareils sans aucune intervention humaine. M2M est aussi vue comme la pierre angulaire de la vision des objets connectés (IoT). Elle attire beaucoup d'attention, car elle peut être considérée comme une nouvelle opportunité pour les opérateurs de réseau et service IoT. Il existe aujourd’hui plusieurs types d’applications se basant sur MTC couvrant plusieurs domaines. On peut citer comme exemples les applications suivantes: la santé, les systèmes de transport intelligents (ITS), les compteurs intelligents et les réseaux intelligents, et la sécurité publique (PS). Le déploiement de ce type d'applications dans les réseaux mobiles cellulaires actuels, particulièrement Long Term Evolution (LTE) et LTE-Advanced (LTE-A) , ne peut être effectif sans surmonter les challenges posés par le déploiement d’un grand nombre d’équipement MTC dans la même cellule. En effet, le déploiement d'une myriade d'appareils MTC causera une congestion et une surcharge du système des réseaux d'accès radio (RAN) et du cœur de réseau (CN). Comme les appareils MTC sont équipés d'une batterie non rechargeable, la consommation d'énergie est aussi un défi. Dans cette thèse, nous allons étudier les problèmes de congestion et de consommation d'énergie dans le contexte des réseaux LTE et LTE-A en présence des appareils M2M. En ce qui concerne la congestion et la surcharge de système, nous nous concentrons sur la partie RAN, puisqu'elle peut être considérée comme la première ligne de défense pour le réseau cellulaire. Les contributions de cette thèse sont organisées sous les axes suivants: 1) Proposition d'un algorithme générique pour prédire le trafic entrant, de sorte que la congestion dans le réseau peut être facilement résolue, 2) Étude et proposition d'un modèle analytique générique de la procédure d'accès aléatoire au canal (RACH). Le modèle a pour but l’évaluation des méthodes de contrôle de congestion ciblant la partie RAN, 3) Approfondissement et proposition des méthodes permettant d'améliorer la méthode Pagination de Groupe (GP) approuvée par le 3GPP pour contrôler la congestion. / The current and next generation wireless cellular networks (5G) have to deal with not only communications between people (known as Human-to-Human - H2H), but also with a massive deployment of Machine-Type-Communication (MTC). MTC, or alternatively Machine-to-Machine (M2M), can be viewed as devices connected among them without any human intervention. M2M can be considered as the cornerstone of Internet-of-Things (IoT) vision. It attracts a lot of attention, since it can be considered as a new opportunity and business market. Nowadays, there is a vast number of MTC applications, covering a large number of fields. Some of these applications are Healthcare, Intelligent Transport System (ITS), smart metering and smart grids, public safety (PS), forming the so-called smart city. Deploying this type of applications in the current cellular mobile networks, especially Long Term Evolution (LTE) and LTE-Advanced (LTE-A), cannot be achieved before overcoming the accompanied challenges. Indeed, caused by the existence of a myriad of MTC devices, Radio Access Network (RAN) and Core Network (CN) congestion and system overload is one of these challenging issues. As the MTC devices are using non-rechargeable batteries, power consumption is also a challenge. In this thesis, we study the congestion and power consumption problems in the context of LTE and LTE-A networks featuring M2M communications. Regarding the congestion and system overload, the focus will be on the RAN part since it can be considered as the first defense line on the network. The contributions of the thesis are organized on the following axes: 1) Propose a general algorithm to predict the incoming traffic, so that the congestion in the network can be easily remedied, 2) Study and propose a general analytical model of the Random Access Channel (RACH) procedure. The model can help to evaluate the congestion control methods targeting the RAN part, 3) Depth study and propose methods improving the performance of Group Paging (GP) method, one of the methods approved by 3GPP to control the congestion.

Magister Commercii - MCom / The main sources of teacher stress stem from difficulty in maintaining classroom discipline, time pressures, workload demands, excessive change, being evaluated by others, challenging relationships with colleagues and poor working conditions. This study therefore highlights the significant relationship between occupational stressors and the stress experienced by teachers at high risk secondary schools in the Western Cape. Occupational stress is related to job satisfaction, job overload and job control. The coping strategies of teachers at high risk secondary schools are explored. The results indicate that there were no significant relationships between teacher stress and job satisfaction, job overload and job control at high risk secondary schools in the Western Cape. Job satisfaction however, showed an inverse, albeit not significant relationship to teacher stress. Furthermore, male and female teachers respond differently to these occupational stressors. Females were more prone to the experience of stress than males. The recommendations are based on the conclusions drawn from the study. In conclusion, occupational stress is considered a major source of stress for teachers, which needs to be addressed more vigorously at high risk secondary schools in the Western Cape. / South Africa

Magister Administrationis - MAdmin / The call centre industry has been one of the fastest growing industries in South Africa. Call centres have for most companies become a basic business requirement for servicing customers. Zapf, Isic, Bechtoldt and Blau (2003: 311) argue that there are high levels of stress amongst employees in call centres, which they believe to be the result of both the work tasks and the interactions with customers. The aim of this study was to establish whether call centre work design and structure contributed to role stress amongst client service representatives (CSRs). It was also the aim of this study to establish whether role stress affected the CSRs' levels of job satisfaction and their intentions to quit from their jobs. / South Africa

The endocrine heart synthesises and secretes two polypeptide hormones: the natriuretic peptides (NP) atrial natriuretic factor (ANF) and B-type natriuretic peptide (BNP). The biological actions of these hormones serve both acutely and chronically to reduce systemic blood pressure and hemodynamic load to the heart, thus contributing to the maintenance of cardiorenal homeostasis. Considerable effort has been focused on the elucidation of the mechanistic underlying ANF and BNP gene expression and secretion but much remains to be determined regarding specific molecular events involved in the cardiocyte secretory function. These hormones are produced by the atrial muscle cells (cardiocytes), which display a dual secretory/muscle phenotype. In contrast, ventricular cardiocytes display mainly a muscle phenotype. Comparatively little information is available regarding the genetic background for this important phenotypic difference with particular reference to the endocrine function of the heart. We postulated that comparison of gene expression profiles between atrial and ventricular muscles would help identify transcripts that underlie the phenotypic differences associated with the endocrine function of the heart as well as identify signaling pathways involved in its regulation. The cardiac atrial and ventricular transcriptomes were analyzed using oligonucleotide microarrays under normal or chronically induced aortocaval shunt volume-overload conditions. Transcriptional differences were validated by RT-PCR and transcripts of interest were knocked-down by RNAi. Comparison of gene expression profiles in the rat heart revealed a total of 1415 differentially expressed genes between normal atrial and ventricular tissues. Functional classification and pathway analysis identified numerous transcripts involved in mechanosensing, vesicle trafficking, hormone secretion, and G protein signaling. Volume-overloaded animals exhibited a progressive increase in cardiac mass over the four-week time course, an increase in expression of known hypertrophic genes, as well as the differential expression of 700 genes within the atria. Volume-overload specifically downregulated the accessory protein for heterotrimeric G protein signaling RASD1 in the atria. In vitro, knockdown of RASD1 in the atrial-derived HL-1 cells, significantly increased ANF secretion, demonstrating a previously unknown negative modulator role for RASD1. The data developed in this investigation provides insight into the expression profiles of genes particularly centered on the secretory function of the heart under normal and chronic hemodynamic overload conditions. Genome-wide expression profile analysis identified RASD1 as being differentially expressed between cardiac tissues as well as being modulated by chronic volume overload. RASD1 emerges as a tonic inhibitor of ANF secretion. The novel function identified herein for RASD1 in the atria is of considerable interest given the fact that secretory impairment of the cardiac natriuretic hormones can negatively impact cardiovascular homeostasis.

The theses is focused on efficient use of numerical methods in development of low-voltage switching devices, namely to create a physically correct and reliable numerical model of the temperature field to find an application in the design of the current path of a device for various operating conditions. The creation of this numerical model requires not only correct inclusion of all modes of heat transfer - conduction, convection and radiation, but also correct solution of problematic transient resistance - both electrical and thermal in electrical contacts at different stages of usage. Therefore an essential part of the theses forms a thorough experimental analysis of the necessary material properties and dependencies which forms input data for the numerical model that is based on the finite volume method. The last part of the theses deals with debugging and verification of numerical model to correspond with experimentally obtained data. The result of the theses is the numerical model which is able to solve correctly both steady and various transient states of swiching devices.

This master‘s thesis deals with the thermal overload trip unit in automatically operated electrical switching devices. The first part of this thesis serves as a basis for a design of thermostatic bimetal element in electrical switching device. The thesis presents important parameters and calculation principles needed for the design of bimetal element. The thesis further describes the operating principle of thermal trip unit and its possible design solutions. The main part is devoted to analytical calculation and measurement of specific thermostatic bimetal type contained in thermal trip unit of molded case circuit breaker. It is measurement of force and deflection, depending on temperature change. In the next part a numerical model of the bimetallic strip was created and its deflection was simulated. The analytical results are compared with the measured and simulated results at the end of the thesis.

The Swedish Energy Agency has a target to increase solar photovoltaics (PV) power production by up to 5-10% of the total electricity demand by the year 2040. The PV potential for the residential market is high and its contribution to the total installed PV capacity is expected to increase significantly. The technical requirements should be met to keep high reliability and good power quality at the customers, therefore, it is important for planning reasons to proactively find the maximum amount PV power that can be connected at each low-voltage network without violating the performance of the grid. This amount is known as the hosting capacity. A method for PV hosting capacity estimation by taking overvoltage and transformer overload as performance indices was developed in this thesis. The method does not require any knowledge about the topology of the network. The overload hosting capacity can be estimated for any combination of customers having PV power and for the overvoltage hosting, the minimum at each penetration level can be estimated. The method was implemented on four low-voltage networks located in a typical Vattenfall medium-voltage network and the comparison of the estimation results to a power flow simulation showed good correspondence. It was shown how the impact of PV power in adjacent secondary substations can be accounted for. Using SS-EN50160 voltage limits, the studied networks were able to handle 3-7 times the PV penetration level needed (8 kWp at 20% of the customers) to achieve the national goal in Sweden without grid investments.