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Geometric invariants play a vital role in the field of object recognition where the objects of interest are affected by a group of transformations. However, designing robust algorithms that are tolerant to noise and image occlusion remains still an open problem. In particular, numerically invariant signature curves in terms of joint invariants, as an approximation to differential invariant signature curves, suffer from instability, bias, noise and indeterminacy in the resulting signatures. The expression presented in the previous works to approximate the affine arc length along the given mesh is only in terms of the approximating ellipse and, in consequence, the current formulae cannot be correctly demonstrated on data containing non-elliptical boundaries. We also prove the current formulation depends on the viewpoint that may change the curve-orientation and the signature-direction, and results in different numerical signatures for congruent ordinary meshes - in other words, Signature Theorem is not correct in Mesh group-planes. In addition, we show that the current expressions do not support a numerical version of Signature-Inverse Theorem- in other words, non-congruent approximating meshes may have the same numerically invariant signatures. Prior to addressing above mentioned issues (except Signature-Inverse Theorem that is not in the scope of this thesis), we first undertake to modify Calabi et al's numerically invariant scheme and refine the current methodology by adding new terminology which improves the clarity and extends the methodology to planar ordinary meshes. To address the issue of stability in the Euclidean formulae Heron's formula is replaced by the accurate area that improves the numerical stability and, in terms of mean square error (MSE) results in a closer approximation in comparison with the current formulation. In the affine geometry, we will introduce a general formulation for the full conic sections to find a numerically invariant approximation of the equiaffine arc length, measured along the given plane curve and between each two points. In addition, closer numerical expressions will be presented that also need fewer points of the given mesh of points to approximate the first order derivative of the affine-curvature compared with the current formulae. Next, we will introduce the first order finite n-difference quotients in both Euclidean and affine signature calculus which not only approximate the first derivatives of the corresponding differential curvatures, but can be also used to minimize the effects of noise and indeterminacy in the resulting outputs. The arising numerical biases in the resulting numerical signatures will be classified as Bias Type-1 and Bias Type-2 and it will be showed how they can be removed. To parameterize numerically invariant signatures independently of the viewpoint, we will introduce an orientation-free version which results in all congruent planar ordinary meshes have the same orientation-free numerically invariant signature, and therefore the Signature Theorem will be correct then in Mesh and Digital group-planes. Finally, we will bring up our experimental results. First the results of applying the proposed scheme to generate numerically invariant signatures will be presented. In this experiment the sensitivity of the parameters used in the algorithm will be examined. These parameters include mesh regularity factors as well as the effect of selecting different mesh resolution to represent the boundary of the object of interest. To reduce noise in the resulting numerical signatures, the n-difference technique and the m-mean signature method will be introduced and will be illustrated that these methods are capable of noise reduction by more than 90%. The n-difference technique will be also applied to eliminate indeterminacy in the resulting outputs. Next, the potential applications of the proposed scheme in object description will be presented by two manners: applying the plots of numerically invariant group-signatures for discriminating between objects of interest by visual judgment, and, quantifying them by introducing the associated group-signature energy. This numerically invariant energy will be demonstrated by using a medical image example.

Facebook Messenger, ChatSecure, Line, QQ and WhatsApp represent examples of Mobile Messaging Applications (MMAs) that collectively facilitate instant and global communications, in which billions of audio, image, text and video messages are exchanged on a daily basis. Some of these messages are digital assets (messages that have a significant functional, sentimental or monetary value) that may be exposed to confidentiality or exploitation threats, wehn published in MMAs that are subject to such security concerns. Additionally, some MMAs impose message format constraints that prevent users from publishing sudio, image and video digital assets in an encrypted form, thus hampering their attempts to mitigate such concerns. In this thesis, two research contributions are presented, that are designed to establish confidentiality over digital assets that are messaged via MMAs. The first contribution, Dual Carrier Steganographic Messaging (DCSM) protocols, pairs two independent and non-colluding MMAs as communication channels, in which a digital asset is steganographically messaged over one MMA and its stego-key (size, format, access information) over the other. The second contribution, extends a probabilistic Hash-based Least Significant Bit (HLSB) steganography technique through the introduction of hash function arrays, and can be applied to JPG images in the spatial domain. This technique features as an integral component in DCSN schemes. Both research contributions are implemented and evaluated via a prototype application, Conceal[sub]2. JPG HLSB embedding is evaluated in a number of configurations that are applied to cover-images with diverse pixel luminance profiles. Subsequent performance results are measured in terms of embedding overheeads, carrier-image distortion ranges, thresholds and embedding scope. Results conclude that JPG HLSB embedding is most efficient when utilising images with wide variations in pixel luminance, and that a configuration utilising an array of 16 hash functions, delivers the best performance of the array sizes tested. Empirical evaluations of 54 Android MMAs conclude that their use as communication channels in DCSM schemes, is feasible where MMAs maintain image integrity and that the successful act of steganographic messaging over viable MMAs without subsequent corruption of carrier-images, indicates that carrier-images are detected but only observed, or that they are not monitored, or that MMA systems are ineffective at detecting the carrier-images utilised in this research.

We present in this thesis the design and development of a new mobile diabetes management system for social behavioural change and management tailored for Saudi diabetic patients (SANAD - Saudi Arabia Networking for Aiding Diabetes). The hey goals of SANAD are to close the diabetes management loop by providing remote monitoring for diabetic patients, a further therapeutic channel to the patient, an opportunity to increase diabetic patients' health awareness, and feedback to help diabetic patients maintain a regular blood glucose level. The key system components consist of: (i) a smart mobile diabetes management module (MDM-M) used for collecting blodd glucose data; (ii) a social networking module (SN-M), acting as an enhancement module for the MDM-M, the key function of which is currently focused on education purposes; and (iii) a cognitive behavioral therapy module (CBT-M),a cting as a supplementary module to MDM-M. This module was designed on the smart mobile platform and used only by patients who require CBT therapeutic intervention. A usability study for the SANAD system is also presented in this thesis to validate the acceptability of using mobile technologies amongst diabetic patient in KSA and Gulf region. The preliminary results of the study indicated general acceptance of the patients in using the system with higher usability rating in type 2 diabetic patients. In general, the study concluded that the concept of SANAD system is considered acceptable tool in particularly with Type 2 diabetes patients. A clinical evaluation study of SANAD system is also conducted in this thesis to evaluate the clinical effectiveness of the system. The primary aim of this study was to evaluate the effect of SANAD system on: 1) improve glycaemic control; 2) improve health awareness; and 3) enhance self-efficacy. Secondary aims qualitatively evaluated the content of communication in SANAD system. The key preliminary results of this study provided in evidence that SANAD has a positive impact on promoting knowledge of diabetes in individuals living with type 2 diabetes, and reflects the generally positive outcomes of reducing glycated hemoglobin control (HbAlc (%)), and increasing self-efficacy.

Intelligence is the power which makes the owner capable of making a decision defined by reasoning. When traditional solutions and approaches, such as First Principal Modelling or Statistical Modelling, are not feasible or able to effectively address complex real- world problems, then Computational Intelligence with some nature-inspired computational techniques and methodologies is employed. For transferring data between two non-directly connected devices when some other devices are in-between, a set of rules are used by routers which are devices between sender and receiver, to determine the most appropriate paths into which routers should forward data toward the intended destination. This set of rules is called routing protocol. Researchers use some computational itelligence techniques to design network routing protocols. Wireless Sensor Networks (WSNs) play an important role in today's data communication systems and researchers are expected to proliferate in the field of wireless communication in the near future. The deployment of wireless sensor networks offer several advantages in comparison to traditional infrastructure-based networks, such as fully distributed mobile operation, the easy discovery of joining wireless devices, and instant and low cost network setup. Designing an effective routing protocol is one of the main challenges in the ad-hoc networking paradigm and the utilisation of an adequate link-cost metric is essential. WSN researchers address issues such as low throughput and high latency in wireless sensor data communication. Routing Protocols in WSNs play a key role in data communication and the main parameter in all routing protocols is data communications link-cost. This research delivers two surveys on existing routing protocols and link-quality metrocs for wireless sensor networks. Most of the routing protocols in this area are considered in different groups. The majority of link-quality metrics in WSNs are studied in different categories. Link-quality and traffic-aware metrics account for most of the metrics, as well as metrics in multi-channel networks and cognitive radio systems, which are also considered in detail. Metrics are reviewed in detail in terms of their performance; summary and comparison tables of link-quality metrics are provided to enable better comparison and show a brief overview of their appearance to get a clearer picture. Routing-metrics are important is determining paths and maintaining quality of service in routing protocols. The most efficient metrics need to send packets to maintain link-quality measurement by using the Radi Frequency (RF) module. In this study, a set of statistical analyses is done on some link-quality metrics to select the best metric for energy-aware scenarios. Two prominent link-quality metrics; Received Signal Strength Indication (RSSI) and Link-Quality Indication (LQI), are described in detail. The symmetry of RSSI and LQI in two directions is studied, and relations with the Expected Transmission Count (ETX), RSSI, and LQI as link-quality metrics are analysed. The evaluation in this research is based on a series of WSN test-beds in real scenarios. Due to implementation of routing protocols in limited power supply devices in WSNs, one novel link-quality metric and also some routing protocols for wireless sensor networks are proposed in this research to obtain better performance in different scenarios. Rainbow Collection Tree Protocol (RCTP) is presented and evaluated as an enhanced version of Collection Tree Protocol (CTP). It uses the Trickle algorithm to optimise overhead cost and the algorithm also makes RCTP quickly adaptable to changes in topology. The Rainbow mechanism is used in RCTP to detect and route around connectivity nodes and avoid routes through dead-end paths. Energy-efficient Rainbow Collection Tree Routing Protocol (ERCRP) is presented and evaluated as a novel, real-time, position-based and energy-efficient routing protocol in this research. ERCRP is a lightweight protocol that reduced the number of nodes which receive the RF signal using a novel Parent Forwarding Region (PFR) algorithm. ERCRP as a Geographical Routing Protocol (GRP) reduced the number of forwarding nodes and thus decreases traffic and packet collision in the network. WSNs are used in three-dimension (3D) scenarios such as sea or land surfaces with different levels of height. Three-Dimension Position-Based Adaptive Real-Time Routing Protocol (3DPBARP) is presented and evaluated as a novel, real-time, position-based and energy-efficient routing protocol for WSNs in this research. 3DPBARP is a lightweight protocol that reduces the number of nodes which received the RF signal using a novel PFR algorithm. 3DPBARP as a GRP decreases the number of nodes which participate in packet forwarding and thus shrink the traffic and collision in the network.

While collaborative learning is universally recognised as a process of considerable pedagogical value, and the enhancement of standard application interfaces to promote collaboration has formed the subject of previous studies, the literature addressing the degree to which Multi-touch technology is used remains limited. Multi-touch, multi-mouse tools are a novel category of groupware, which can enhance learning through collaborative use of those tools. The research aim is to develop a framework and a software tool known as the Learning to Program through a Computer-Aided Collaboration (LPCAC) tool. The LPCAC is a Multi-touch software tool that enhances the learning of computer programming in university through collaborative use of this tool. Subsidary objectives are pursued in the form of research questions, with most comparatively investigating and evaluating the use of the Multi-touch tool compared to the standalone PC-based approach. University students were selected to take part in a study to measure their performance improvements using the Multi-touch tools in a collaborative environment. A two-part process was followed to analyse the difference between student collaborations using Multi-touch with multi-mouse devices cmpared to standalone PC-based system with a single mouse device. Data collection involved video recording and a questionnaire analysis. Data analysis followed an eight-step process to evaluate the process of collaborative programming, which includes an analysis of collaboration patterns, time on task, equity of participation and design quality. While the Multi-touch tool is limited in a number of ways, its multiple points of contact and the collaborative activity promote a more favourable software design process when compared to the standalone PC-based condition. Although further research is needed, this study has found that Multi-touch technology represents a promising prospect for application in teaching computer programming in educational establishments, as well as improving the software development process in the wider collaborative software development.

<p>Denna uppsats tar upp frågan om drivkrafter hos svenska personer som idag driver en blogg av personlig karaktär. Den huvudsakliga frågeställningen lyder: ”Vad är drivkraften bakom bloggande hos svenska bloggare?”. Bloggens popularitet och framfart de senaste åren gör den lättillgänglig som läsare men också som bloggförfattare, vem som helst kan idag enkelt skapa en egen blogg och börja blogga. Vad är det då som driver svenska bloggare till att starta och sedan kontinuerligt driva en blogg? Vad skulle kunna få en bloggare att sluta blogga? Empirin samlas in från relaterad forskning och intervjuer av svenska bloggare med ett kvalitativt angreppssätt. Resultaten bekräftar tidigare forskning som slår fast att svenska bloggare drivs av att skriva av sig, att det är roligt att blogga eller för den sociala interaktionens skull. Resultaten visar också tendenser till samband i drivkrafter mellan olika grupperingar av bloggare. Däribland att yngre bloggare oftare tenderar att bry sig om bloggens publicitet och status, bloggare som använder sin blogg som ett substitut till dagbok lägger mindre vikt vid den sociala interaktion som bloggen kan medföra och bloggare som oftare bloggar om problem tenderar till att vilja hålla sin familj utanför läsarkretsen. Slutsatsen är att enskilda individer drivs av olika faktorer, men att olika kategorier av bloggare tenderar att drivas av liknande faktorer.</p>

<p>Organisations and projects use CSCW/Groupware systems for collaboration purposes. These systems and applications are in many cases using a non-transparent GUI, witch is also hard to learn. This paper present a novel system that aims towards being transparent and easy to use. This system, called CollMX, will be evaluated and different ideas for future development will be presented.  The evaluation and ideas are generated by an empiric evaluation and research in different areas related to CSCW. The research does not only focus on the area of CSCW, but also extends towards the Web 2.0 and ideas about awareness.</p>

<p><em> </em></p><p><em><p>Today, we can see that social navigation is embedded in different kinds of websites, but there is still little support for social navigation in the web browser. Our main concern has been how we construct a tool that fills this hole in the web browser. By letting the theory, the prototype and the focus group serve as input/output to each other we could create a better overview of how the different pieces were intertwined. This has been a crucial mental model for us to obtain since it has helped us to understand how we could realize the theory through our prototype and thereby come to the conclusion of what aspects of the theory that we should put forward to further development. After constructing the prototype we thought that it would support social navigation, but realized after analyzing the discussion of the focus group that we are not there yet. Our conclusion after analysing the discussion is that more emphasis on trust, privacy and presence must be taken under consideration.</p></em></p><p> </p>