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This work has been done by three development engineers and one computer engineer and in some cooperation with the company Phoniro. This report is written for computer science and is mainly oriented on the programming part in the project. The goal has been to develop a program that ensures the quality of the care that the home care organization delivers. The program is developed for cellphones and is supposed to be used in every visit. Several functions have been developed for the reason of reducing mistakes in patient visits, where the focus was on safe medication. The program also contributes to other benefits such as reduced paper handling, fewer phone calls where information is requested and creates a standard procedure for all visits.The work has been performed in the way where the development engineers has identified new functions and made a requirement specification that have been further developed by a com-puter engineer in java against cellphones.

This thesis presents a study of the signed distance function as a three-dimensional implicit surface representation and provides a detailed overview of its different properties. A method for generating such a representation using the depth-image output from a Kinect camera is reviewed in detail. In order to improve the quality of the implicit function that can be obtained, registration of multiple sensor views is proposed and formulated as a camera pose-estimation problem. To solve this problem, we first propose to minimize an objective function, based on the signed distance function itself. We then linearise this objective and reformulate the pose-estimation problem as a sequence of convex optimization problems. This allows us to combine multiple depth measurements into a single distance function and perform tracking using the resulting surface representation. Having these components well defined and implemented in a multi-threaded fashion, we tackle the problem of object detection. This is done by applying the same pose-estimation procedure to a 3D object template, at several locations, in an environment reconstructed using the aforementioned surface representation. We then present results for localization, mapping and object detection. Experiments on a well-known benchmark indicate that our method for localization performs very well, and is comparable both in terms of speed and error to similar algorithms that are widely used today. The quality of our surface reconstruction is close to the state of the art. Furthermore, we show an experimental set-up, in which the location of a known object is successfully determined within an environment, by means of registration. i

Humanoid robotics is a challenging and promising research field. Legged locomotion is one of the most important aspects of it. In spite of the progress achieved in the last years in control of walking robots, many problems are yet to be resolved. The inherent complexity of such robots makes their control a difficult task even on the modern hardware. In order to address this issue approximate models and high performance algorithms are employed. This thesis is focused on the model predictive control of a walking bipedal robot, which is approximated by an inverted pendulum, using online optimization. A special emphasis is made on the solvers that exploit the structure of quadratic optimization problems in the context of model predictive control. Two methods for solution of these problems are implemented: primal active set and primal logarithmic barrier methods. They are tested and compared in a simulation and on a humanoid robot. A software module for control of the Nao humanoid robot is developed for this purpose.

WLANs are become popular due to their different advantages. Beside all these advantages WLANs are also facing the major problem of the security, so that why lots of people are doing research on WLAN to improve the security because many companies want to transfer their sensible data over WLAN. This report discusses the security issues of WLAN based on IEEE 802.11 standard, such type of networks are referred to as wifi network. WLAN is deployed as an extension of already existed wired LAN. Therefore it is necessary to provide the security of WLAN equals to Wired LAN. We worked in a lab environment in order to configure the three different security solutions (WEP, WPA & WPA2 using IEEE 802.1X and RADIUS Server) on infrastructure mode for personnel and enterprise architecture of WLAN. For each security solution we used the backtrack as a security cracking tool, in order to break the WEP (64 and 128 bit long) security key of WLAN, make comparison between 64 and 128 bit long WEP key and also analyzed the different kind of attacks  and some drawbacks of using WEP security in WLAN. In the same way configure the WPA and WPA2 (using IEEE 802.1X and RADIUS Server) security solution in infrastructure mode of WLAN and use the same security cracking tool backtrack in order to break the security of the WLAN and analyze the different attacks on the network in these architecture and drawbacks of using WPA and WPA2 Security solutions. By using IEEE 802.1X and RADIUS Server we can improve the security of the enterprise network. In the end we come with many conclusions and suggestions that will help in order to provide better security while deploying Wireless LAN. / Opponents: Ali Murtaza & Mansoor Ahmed

In distributed heterogeneous computing environments, such as in-home entertainment networks and mobile computing systems, independently developed applications share common resources, e.g., CPU or network bandwidth. The resource demands coming from different applications are usually highly fluctuating over time. For example, video processing results in both stochastic fluctuations, caused by different coding techniques for video frames, and structural fluctuations, due to scene changes. Similarly, wireless networks applications are exposed to long-term bandwidth variations caused by other application in the system that are using the same wireless network simultaneously, and short-term oscillations due to radio frequency interference, like microwave ovens or cordless phones. Still, applications in such open, dynamic and heterogeneous environments are expected to maintain required performance levels. In this thesis, we look into solutions for efficient transport of video streams with acceptable playout quality in home networks, which requires management of both networks and CPUs. We propose a framework for efficient resource management for streaming in heterogeneous system, called the Matrix. The Matrix is based on a global abstraction of device states, which reduces system state information and decreases overheads for its determination and dissemination. It provides access to the entire system state in acceptable fresh way, enabling system wide optimized decisions to be taken. Moreover, we use the Matrix framework as the platform to develop a method for an efficient Quality-of-Service (QoS) provision and adaptation in dynamic, heterogeneous systems. QoS adaptation is one of the crucial operations to maximize overall system quality as perceived by the user while still satisfying individual application demands. It integrates local QoS mechanisms of the involved devices that deal mostly with short-term resource fluctuations, with a global adaptation mechanism that handles structural and long-term load variations on the system level. We have illustrated the effectiveness of our QoS adaptation approach in the context of video streaming. However, we do not see any limitation to expand the usage of our approach to the health sector, or some other community social/industrial applications. Resource management and QoS adaptation are required whenever we are surrounded with heterogeneous, mobile, and dynamic environment.

Formal methods are becoming mature enough to be used on nontrivial examples. They are particularly well fitted for real-time systems whose correctness is defined in terms of correct responses at correct times. Most common real-time systems are of reasonable size and can therefore be handled by an automatic verification tool such as Uppaal. Unfortunately the application of such techniques is not widely spread. This thesis presents advances in making formal techniques more accessable technology for system development and analysis. As the first contribution, we report on an industrial case study to show that model checkers can be used for debugging and error localization. We shall present a number of abstraction techniques applied in the case study to avoid the state explosion problem. As the second contribution, we have developed a hierarchical extension of timed automata to enable more structured, compact, and more complex descriptions of systems by the users. Such a hierarchical representation is better suited for abstraction and expected to give better searching algorithms. Finally we present a hybrid animation system serving as a plug-in module for model-checkers to improve features for modelling and simulation.

In this thesis, we study executable behaviours of timed models. The focus is on synthesis of executable code with predictable behaviours from high level abstract models. We assume that a timed system consists of two parts: the control software and the plant (i.e. the environment to be controlled). Both are modelled as timed automata extended with real time tasks. We consider the extended timed automata as design models. We present a compilation procedure to transform design models to executable code including a run-time scheduler (run time system) preserving the correctness and schedulability of the models. The compilation procedure has been implemented in a prototype C-code generator for the brickOS operating system included in the Times tool. We also present an animator, based on hybrid automata, to be used to describe a simulated environment (i.e. the plant) for timed systems. The tasks of the hybrid automata define differential equations and the animator uses a differential equations solver to calculate step-wise approximations of real valued variables. The animated objects, described as hybrid automata, are compiled by the Times tool into executable code using a similar procedure as for controller software. To demonstrate the applicability of timed automata with tasks as a design language we have developed the control software for a production cell. The production cell is built in LEGO and is controlled by a Hitachi H8 based LEGO-Mindstorms control brick. The control software has been analysed (using the Times tool) for schedulability and other safety properties. Using results from the analysis we were able to avoid generating code for parts of the design that could never be reached, and could also limit the amount of memory allocated for the task queue.

Software is characterized by inevitable changes and increasing complexity, which in turn may lead to huge costs unless rigorously taking into account change accommodations. This is in particular true for long-lived systems. For such systems, there is a need to address evolvability explicitly during the entire lifecycle, carry out software evolution efficiently and reliably, and prolong the productive lifetime of the software systems. In this thesis, we study evolution of software architecture and investigate ways to support this evolution.           The central theme of the thesis is how to analyze software evolvability, i.e. a system’s ability to easily accommodate changes. We focus on several particular aspects: (i) what software characteristics are necessary to constitute an evolvable software system; (ii) how to assess evolvability in a systematic manner; (iii) what impacts need to be considered given a certain change stimulus that results in potential requirements the software architecture needs to adapt to, e.g. ever-changing business requirements and advances of technology. To improve the capability in being able to on forehand understand and analyze systematically the impact of a change stimulus, we introduce a software evolvability model, in which subcharacteristics of software evolvability and corresponding measuring attributes are identified. In addition, a further study of one particular measuring attribute, i.e. modularity, is performed through a dependency analysis case study. We introduce a method for analyzing software evolvability at the architecture level. This is to ensure that the implications of the potential improvement strategies and evolution path of the software architecture are analyzed with respect to the evolvability subcharacteristics. This method is proposed and piloted in an industrial setting. The fact that change stimuli come from both technical and business perspectives spawns two aspects that we also look into in this research, i.e. to respectively investigate the impacts of technology-type and business-type of change stimuli.

Real-Time Systems are computer systems with constraints on the timing of actions. To ease the development and maintenance of application software, Real-time Systems often make use of a Real-Time Operating System (RTOS). Its main task is scheduling of application processes (tasks). Other functions can be interprocess communication, interrupt handling, memory management etc. Sometimes it is hard (or even impossible) to meet the time constraints specified for a real-time system, resulting in an incorrectly functioning application. A possible remedy is to redesign the system by upgrading the processor and/or remove functionality, etc. An alternative solution could be the use of a special purpose hardware accelerated RTOS. The aim of such an accelerator is to speedup RTOS functions that impose big overhead i.e. to reduce the kernel overhead by offloading the application processor. Accordingly, the processor gets more time for executing application software, and hopefully the time constraints can be met. The main drawback is the cost of extra hardware. This thesis presents results from implementing RTOS functions in hardware, especially interprocess communication (IPC) functions. The types of systems considered are uniprocessor and shared memory multiprocessor real-time systems. IPC is used in systems with co-operating processes. The operating systems on the market support a large variation of IPC mechanisms. We will here present and evaluate three different IPC implementations. The first is an extended message queue mechanism that is used in commercial robot control applications. The second is the signal mechanism in OSE, a commercial RTOS predominantly used in telecommunication control applications, and the third is the semaphore and message queue mechanisms supported by the leading commercial RTOS VxWorks. All the implementations are based on a pre-emptive priority-based hardware real-time kernel accelerator. We show that it is not optimal, practical or desirable to implement every kernel function into hardware, regarding systems in the scope of this thesis. However, an accelerator allows new functionality to be implemented. We illustrate this by implementing a message queue mechanism that supports priority inheritance for message arrival in hardware, which is too expensive to implement in software. Also, we show that substantial speedups are possible, and that a crucial mechanism in achieving speedup is the accelerator-processor interconnect. We further note that application speedups are possible, even in cases with an IPC-mechanism slow-down. The main reasons for this is that the accelerator can off-load the processor by handling the RTOS timing mechanism (clock-ticks), reducing the RTOS code to be executed on the processor, and handling interrupts.