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The IKEA customers are looking for new solutions to mount products in their homes and IKEA has embraced the request for this type of applications in bathroom environments as it is of the largest challenges for the customer. Double sided tape has been identified as a possible solution, hence why this project was put together. The research aims to give the reader a deeper understanding regarding double sided tape and the influences of external variables such as material, substrate and surface tension to mention a few. Extensive tests have been carried out where samples from double sided tape suppliers are examined. The test that was developed and carried out in this project aimed to include some of IKEA´s most commonly used materials together with common substrates in bathroom environments. The test data was compiled and the outcome was used to give recommendations to IKEA regarding future product development when using double sided tape and also recommend suitable tape suppliers for continued cooperation.

Mycobacterium tuberculosis remains one of the most common worldwide causes of illness and death due to an infectious disease. The emergence of multiple and extreme-drug resistant strains has increased the need to find an effective vaccine for tuberculosis. The goal of our research group is to engineer a temperature-sensitive (TS) M. tuberculosis strain that can be used as a tool in vaccine development. One approach to create TS M. tuberculosis involves the integration of the essential gene ligA encoding a TS NAD+ dependent DNA ligase, which was taken from the psychrophilic organism Pseudoalteromonas haloplanktis. The integration and functioning of ligA was demonstrated in the fast-growing organism Mycobacterium smegmatis. This strain had a TS phenotype with growth limited to below 37°C. The strain was found to have a stable TS phenotype and did not mutate to a temperature-resistant form at a detectable level. Following experiments with the fast growing M. smegmatis, the integration of the ligA gene was attempted in slow-growing M. tuberculosis. Merodiploids of M. tuberculosis containing both the psychrophilic and the WT ligA gene in its chromosome were obtained. The second approach used for the development of TS M. tuberculosis was the directed evolution of native M. tuberculosis essential genes. An advantage of this approach is that the gene encoding the essential protein will resemble the native M. tuberculosis gene and thus will closely match the native transcriptional and translational rates. A system to screen and select for TS essential genes engineered by directed evolution was designed, where the essential gene on the chromosome of E. coli was knocked out and this gene was supplied on a conditionally replicating plasmid. As a first step in developing this directed evolution approach, a family of conditionally replicating plasmids were created and tested in an essential gene knock-out strain of E. coli. / Graduate

Limb haemodynamic responses during heat-stress and the importance of local vs. central temperature-sensitive mechanisms towards their regulation remain poorly understood, both at a whole-limb level and within individual tissues (i.e. skeletal muscle and skin). The aims of this thesis were to 1) investigate the haemodynamic responses at rest to direct thermal challenges both at a local level and during progressive elevations in systemic heat stress, 2) to ascertain the contribution of local vs. systemic mechanisms towards this regulation, and 3) to investigate the same responses during single-legged small-muscle mass exercise to near maximal levels. Results from Chapters 4 and 5 characterised the haemodynamic responses during isolated cooling and heating of the arm and leg, and provided evidence of alterations in both skin and skeletal muscle blood flow controlled solely through local temperature-sensitive mechanisms. While local cooling led to modest decreases in limb blood flow due to decreases in mean blood velocity alone, increases during heating occurred as a result of an increased antegrade flow, a diminished retrograde flow, and a reduction in the potentially pro-atherogenic oscillatory shear index. In Chapter 6, whole-body heating with isolated single leg cooling displayed the continued control of limb blood flow via local thermosensitive mechanisms alone, as cooled leg blood flow remained unchanged despite significant elevations in core temperature, cardiac output, and opposing heated leg blood flow. Furthermore, elevations in heated leg V̇O2 suggested a possible metabolic contribution to the observed skeletal muscle hyperaemic response. During incremental single-legged knee-extensor exercise to near maximal levels, blood flow was determined by a combination of metabolic workload and local tissue temperatures, regardless of whether systemic heat stress was present. Chapter 7 revealed that whilst skin and muscle blood flow in the leg continued to increase in line with local temperatures to levels of severe heat stress, rapid cooling of the leg when hyperthermic resulted in a similar reverse response in muscle tissues only, as skin blood flow remained elevated despite the abolition of high skin and subcutaneous temperatures. In addition, evidence was provided that moderate levels of whole-body heat stress provided little additional benefit to anti-atherogenic shear profiles than that experienced during isolated limb heating alone. Taken together, these findings suggest that local thermosensitive mechanisms dominate limb blood flow control during direct rapid heating in humans both at rest and during small muscle mass exercise, but that underlying central mechanisms may act to maintain flow when local temperatures are reduced in the face of high core temperatures.

This thesis aims to explore the two dominant functional roles of the hippocampal formation, in the relational encoding of episodic memory and the neural representation of allocentric space, using a combination of pharmaceutical manipulations and single-unit recording techniques in rodents. The first part of this thesis focuses on episodic-like memory, defined by the original episodic memory triad: ‘what-where-when’ (Tulving 1972), which enables the behavioural aspects of episodic memory to be tested in non-human animals. Permanent neurotoxic lesions of the hippocampus and it’s subregions were induced to assess their role in a putative episodic-like memory task developed by Eacott and Norman (2004). In view of the difficulties encountered in successfully demonstrating the temporal component of episodic-like memory in rats, this task tested integrated memory for ‘what-where-which’, where the temporal component (when) was replaced with another event specifier: context (on ‘which’ occasion). Disruption of the hippocampal circuitry led to a specific impairment in the integration of all three event components, whereas the associative recognition of any combination of these features in isolation was left intact. These results confirm the hippocampal dependence of this episodic-like memory task and further reveals the necessity of both CA3 and CA1, hypothetically due to the underlying autoassociative role of CA3 with CA1 functioning as the vital output pathway for this associated information and/or as a mismatch detector. There has been much debate over the inclusion of the temporal component and sceptics may argue that any such interpretations of task-dependence on episodic-like memory processing are invalid considering the requirement for temporal processing is absent. Due to the proposal that a temporal framework necessarily provides the foundation on which episodic memories are built, the second chapter focuses on the development of a suitable protocol in which integrated memory for the original ‘what-where-when’ episodic memory triad can be reliably tested. The other main function attributed to the hippocampus was brought to light by the fascinating revelation that it’s neurons selectively fire in different regions of an environment, termed ‘place cells’ (O’Keefe and Dostrovsky 1971). From the numerous publications resulting from this discovery it has emerged that place cells not only respond to the spatial features of the environment but are also sensitive to a multitude of non-spatial features. These characteristics support the logical assumption that the primary firing patterns of the hippocampus should underlie it’s main purported roles, leading to speculations that they reflect episodic memory processes. The second part of this thesis aims to examine the relationship between hippocampal cells and behaviour by extending the work of Ainge et al. (2007a), in which a subset of hippocampal place cells were found to encode both current and intended destination in a double Y-maze ‘win-stay’ task. The development of these ‘goal-sensitive’ cells were initially investigated during the learning phase of this task. An exciting pattern of results showed a strong positive correlation between the emergence of goal-sensitive firing and behavioural performance on the task, tempting speculations that these firing patterns may underlie spatial learning and future planning, necessary to support performance. To ensure these firing patterns were not a mere reflection of greater experience on the maze, a second study was conducted in which the task demands changed over set periods of days. A significant increase in the proportion of cells demonstrating goal-sensitive firing was revealed when the protocol shifted to incorporate the spatial memory demands of the ‘win-stay’ task, with all other parameters of the protocol remaining constant. These results support the theory that goal-sensitive firing patterns are specifically related to the learning and memory demands of the spatial task, not a result of increased exploration of the maze. The last of this series of studies assessed hippocampal-dependence of this task and revealed that bilateral hippocampal lesions induced an impairment in spatial ‘win-stay’ performance. Collectively, these experiments demonstrate that goal-sensitive firing of hippocampal cells emerge in line with behavioural performance in a hippocampal-dependent task and the emergence of these firing patterns are specific to the learning and memory demands of a spatial ‘win-stay’ protocol. The functional role of the hippocampus in allocentric spatial processing may thus underpin it’s function in episodic memory and potentially in the imagining and planning of future events, whereby the hippocampus provides a ‘space’ in which retrieved information can be integrated in a coherent context to support the fluent and flexible use of information. This hippocampal function would necessarily require visual information to be accessed, concerning the arrangement of landmarks and cues within the environment, in association with information regarding internal orientation and direction and this leads to the question assessed in the final part of this thesis of where this integration occurs. Based on anatomical evidence and the current literature, the postsubiculum, an input structure to the hippocampus, emerged as a potential site for the convergence of sensory cues into the internally generated head direction cell and place cell networks to enable hippocampal-dependent spatial processing. Thus, the effects of temporary pharmacological blockade of AMPARs and NMDARs in the postsubiculum were assessed on the encoding of spatial memory in an object recognition paradigm. The impairment revealed in the ability to recognise novel object-place configurations demonstrates a key role for NMDAR-dependent plasticity within the postsubiculum itself in the formation of allocentric spatial memory. In summary, the experimental results reported in this thesis further elucidate the critical role the hippocampal formation plays in spatial and episodic memory by combining evidence from cellular physiology and neuroanatomy to the behaving animal and extends these findings to discuss a more general role for the hippocampus in imagining both past and future events, in order to successfully navigate, learn and enable past experience to influence our intended future plans and decisions.

Every member of the organization must be involved in proactively and consistently preventing data loss. Implementing a culture of security has proven to be a reliable method of enfranchising employees to embrace security behavior. However, it takes more than education and awareness of policies and directives to effect a culture of security. Research into organizational culture has shown that programs to promote organizational culture - and thus security behavior - are most successful when the organization's values are congruent with employee values. What has not been clear is how to integrate the security values of the organization and its employees in a manner that promotes security culture. This study extended current research related to values and security culture by applying Value Sensitive Design (VSD) methodology to the design of an end user security policy. Through VSD, employee and organizational security values were defined and integrated into the policy. In so doing, the study introduced the concept of value sensitive security policy (VSP) and identified a method for using VSPs to promote a culture of security. At a time when corporate values are playing such a public role in defining the organization, improving security by increasing employee-organization value congruence is both appealing and practical.

Buffer Overflows are a common type of network intrusion attack that continue to plague the networked community. Unfortunately, this type of attack is not well detected with current data mining algorithms. This research investigated the use of Random Forests, an ensemble technique that creates multiple decision trees, and then votes for the best tree. The research Investigated Random Forests' effectiveness in detecting buffer overflows compared to other data mining methods such as CART and Naïve Bayes. Random Forests was used for variable reduction, cost sensitive classification was applied, and each method's detection performance compared and reported along with the receive operator characteristics. The experiment was able to show that Random Forests outperformed CART and Naïve Bayes in classification performance. Using a technique to obtain Buffer Overflow most important variables, Random Forests was also able to improve upon its Buffer Overflow classification performance.

Services based on the Information and Communications Technologies (ICT) are present more and more in the lives of people. The advancement of ICT in technical and social acceptance terms has led the creation of new models of service provision. These provision models involve further integration with people's activities so that are not only present in their professions or civic space but also in a more intimate areas related to their own identity. So it is now common to find services aware of user's health, their domestic habits, ideology, etc. Therefore, the analysis of existing services must be open out to include other aspects related to the way of being and feeling of their members. This way is possible to ensure both the technical correctness of its features as promoting safe and respectful solutions both of civic rights as the way of being and feeling of its members. From the engineering point of view, the user perspective has historically encompassed under the concept of technological acceptance. Within this field can be interpreted as friendly solutions adapted to users will encourage the acceptance by them. Solution acceptance is desirable although it is difficult to ensure. This difficulty is due to the lack of the number of variables that affect the acceptance of technological solutions and the difficulty of optimizing the known variables. In this thesis it is studied and characterized one of the variables that affect the acceptance of existing services: confidence. Confidence is defined in psychological terms, providing its characterization with the aim of be used in typical methods of engineering. Also different tools are proposed to facilitate the optimization of this confidence in services whose complexity establishes this variable in a basic issue to improve acceptance. Health services deployed in a home have been chosen as working context for this thesis. This scenario presents a number of acceptance restrictions on the technology used to create services and how they manage the acquired user information. It comes to highly sensitive and delocalized services that can affect to the user's perception of the environment, the home, and generate fear or rejection to prevent final adoption as a valid solution. Once defined the generic framework, the main objective of this dissertation is focused on promote the acceptance of new pervasive and personalized health services and their deployment in domestic intelligent environments through a layout that promotes a psychological state of confidence in users. To achieve this goal, a set of results, both conceptual, technological and experimental, have been provided. In particular, it has offered a complete characterization of the feeling of confidence from a viewpoint of engineering and a definition of sensitive or delocalized pervasive service. Furthermore, a method for the inclusion of the Interaction Design discipline in engineering processes of such services through a set of patterns of interaction is offered. Finally, this thesis provides the development of a software architecture to ensure proper deployment of these pervasive sensitive services in intelligent environments in a confident way. Discussion of the results suggests the extension of the deployment model to different services of the Information Society that handle sensitive data both in the context of the digital home and other settings where the user perform everyday activities such as work spaces or schools. The future work lines include the imminent need to apply the results to ongoing developments, within research projects in those the author takes part, and the development of new research lines aimed at creating new spaces and interaction technologies as advanced accessible interfaces, toys of the future, confident visualization systems or security systems based on the condition of the user. / Tjänster baserade på informations- och kommunikationsteknik (IKT) blir allt mer vanligare i människors liv. För att främja acceptansen för IKT i både tekniska och sociala aspekter av människors liv har nya modeller för dessa tjänster skapats. Dessa modeller har en närmare knytning till människors verksamhet så att de inte bara förekommer i deras yrken eller fritid men också i mer intima områden som anknyter till individens egen identitet. Det är nu därför vanligt att hitta tjänster som tar hänsyn till användarens hälsa, vanor, ideologi, etc.  En analys av befintliga tjänster måste inkludera dessa aspekter men även användarnas känsla av identitet och medlemskap. På detta sätt är det möjligt att säkerställa den tekniska riktigheten hos dessa funktioner som i sin tur borgar för säkra och respektfulla lösningar som tar hänsyn till medlemmarnas medborgerliga rättigheter likväl som deras känsla av identitet och medlemskap. Historiskt sett, och ur ett tekniskt perspektiv, har användarperspektivet omfattats under begreppet teknisk acceptans. Inom detta område har användarvänliga lösningar anpassade till användarna själva uppmuntrat acceptans av dem. Acceptans av lösningar är önskvärt även om det är svårt att säkerställa. Denna svårighet beror på avsaknaden av antalet variabler som påverkar acceptansen av tekniska lösningar och svårigheten att optimera de kända variablerna. I denna avhandling studeras och karaktäriseras en av de variabler som påverkar acceptansen av befintliga tjänster: förtroende. Förtroendet definieras i psykologiska termer med syftet att kunna använda termen i typiska metoder för teknik. Det föreslås också olika verktyg för att underlätta optimering av detta förtroende inom tjänstesektorn. Hälso- och sjukvård i hemmet har valts som scenario för denna avhandling. Detta scenario presenterar ett antal restriktioner med avseende på acceptansen av den teknik som används för att skapa tjänster och hur dessa tjänster hanterar den förvärvade användarinformationen. För användaren är situationen mycket känslig och de erbjudna tjänsterna kan påverka användarens uppfattning av miljön och hemmet och/eller generera rädsla eller avsmak för att acceptera lösningen. När den generiska ramen är etablerad är det huvudsakliga syftet med denna avhandling att främja acceptans av nya tjänster för personlig hälsovård och deras användning i hemmet. Detta skall uppnås genom en layout som främjar ett psykologiskt förtroende hos användarna. För att uppnå detta mål har en uppsättning resultat, både begreppsmässiga, tekniska och experimentella, analyserats. Framför allt har en fullständig karaktärisering gjorts av känslan av förtroende från en teknologisk synvinkel och en definition av en känslig och allomfattande tjänst. Dessutom framläggs en metod för införandet av interaktionsdesign i de aktuella tjänsterna genom ett antal interaktionsmönster. Slutligen behandlar denna avhandling utvecklingen av en mjukvaruarkitektur för att säkerställa en korrekt användning av dessa känsliga tjänster. Resultaten pekar på att distributionsmodellen även kan användas för andra tjänster i informationssamhället där användaren utför vardagliga sysslor, såsom i det digitala hemmet eller andra miljöer (t.ex. skolor och arbetsplatser), där känsliga uppgifter hanteras. De framtida arbetsuppgifterna omfattar det överhängande behovet av att tillämpa resultaten på den pågående utvecklingen av forskningsprojekt som författaren är involverad i. Detta omfattar även utveckling av ny forskning som syftar till att skapa ny interaktionsteknik t.ex. avancerade gränssnitt, framtida leksaker, säkra visualiseringssystem eller säkerhetssystem baserat på användarens hälsa/tillstånd. / <p>This PhD research has been conducted under a double PhD agreement degree between the School of Telecommunications Systems and Engineering (ETSIST) at the Technical University of Madrid (UPM) in Spain and the School of Technology and Health (STH) at the Royal Institute of Technology (KTH) in Sweden.</p><p>QC 20160129</p>

Thesis (MSc (Physics))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: Neutrino and antineutrino detection is a fairly new eld of experimental physics, mostly due to the small interaction cross section of these particles. Most of the detectors in use today are huge detectors consisting of kilotons of scintilator material and large arrays of photomultiplier tubes. Direction sensitive antineutrino detection has however, not been done (at the time of writing of this thesis). In order to establish the feasibility of direction sensitive antineutrino detection, a Monte Carlo code, DSANDS, was written to simulate the detection process. This code focuses on the neutron and positron (the reaction products after capture on a proton) transport through scintilator media. The results are then used to determine the original direction of the antineutrino, in the same way that data from real detectors would be used, and to compare it with the known direction. Further investigation is also carried out into the required amount of statistics for accurate results in an experimental eld where detection events are rare. Results show very good directional sensitivity of the detection method. / AFRIKAANSE OPSOMMING: Neutrino en antineutrino meting is 'n relatief nuwe veld in eksperimentele sika, hoofsaaklik as gevolg van die klein interaksie deursnee van hierdie deeltjies. Die meeste hedendaagse detektors is massiewe detektors met kilotonne sintilator materiaal en groot aantalle fotovermenigvuldiger buise. Tans is rigting sensitiewe antineutrino metings egter nog nie uit gevoer nie. 'n Monte Carlo kode, DSANDS, is geskryf om die meet proses te simuleer en sodoende die uitvoerbaarheid van rigting sensitiewe antineutrino metings vas te stel. Hierdie kode fokus op die beweging van neutrone en positrone (die reaksie produkte) deur die sintilator medium. Die resultate word dan gebruik om die oorspronklike rigting van die antineutrino te bepaal, soos met data van regte detektors gedoen sou word, en te vergelyk met die bekende oorspronklike rigting van die antineutrino. Verder word daar ook gekyk na die hoeveelheid statistiek wat nodig sal wees om akkurate resultate te kry in 'n veld waar metings baie skaars is. Die resultate wys baie goeie rigting sensitiwiteit van die meet metode.

Active learning techniques aim to reduce the amount of labeled data required for a supervised learner to achieve a certain level of performance. This can be very useful in domains where unlabeled data is easy to obtain but labelling data is costly. In this dissertation, I introduce methods of creating computationally efficient active learning techniques that handle different misclassification costs, different evaluation metrics, and different label acquisition costs. This is accomplished in part by developing techniques from utility-based data mining typically not studied in conjunction with active learning. I first address supervised learning problems where labeled data may be scarce, especially for one particular class. I revisit claims about resampling, a particularly popular approach to handling imbalanced data, and cost-sensitive learning. The presented research shows that while resampling and cost-sensitive learning can be equivalent in some cases, the two approaches are not identical. This work on resampling and cost-sensitive learning motivates a need for active learners that can handle different misclassification costs. After presenting a cost-sensitive active learning algorithm, I show that this algorithm can be combined with a proposed framework for analyzing evaluation metrics in order to create an active learning approach that can optimize any evaluation metric that can be expressed as a function of terms in a confusion matrix. Finally, I address methods for active learning in terms of different utility costs incurred when labeling different types of points, particularly when label acquisition costs are spatially driven. / text