We present the BIP component framework for component-based construction of real-time systems from heterogeneous components. BIP stands for Behavior, Interaction and Priority, the three main elements for building components. It considers that systems can be obtained by composition of 3-layered components, where the lowest layer represents behavior as a set of transitions with triggers and actions; the intermediate level is the set of the interactions between the transitions of the behavior level, and the upper level is a set of dynamic priority rules. BIP has a rigorous formal semantics, and supports a system construction methodology based on a parameterized composition operator on components. The use of a layered composition operator allows incremental construction. The system construction process can be viewed as a sequence of transformations in a three-dimensional space of Behavior X Interaction X Priority, and provides a basis for the study of property preserving transformations between subclasses of systems such as untimed/timed, asynchronous/synchronous. We also provide a distributed semantics for systems in BIP, using a partial state model, and show the use of an auxiliary predicate called Oracle to preserve observational equivalence with respect to the centralized semantics. We present an implementation of BIP as a tool chain that allows modeling, static analysis and execution of BIP descriptions on a dedicated engine. Three different implementations for the engine have been provided, a centralized enumerative engine, a centralized symbolic engine and a distributed engine. We illustrate the use of the tool chain for two major application domains, Software Componentization, and Modeling mixed hw/sw systems.

<p>For many years OSE has been a common used operating system, with real time extensions enhancements, in embed-ded systems. But in the last decades, Linux has grown and became a competitor to common operating systems and, in recent years, even as an operating system with real time extensions. With this in mind, ÅF was interested in replacing the quite expensive OSE with some distribution of the open source based Linux on a PowerPC MPC8360. Therefore, our purpose with thesis is to implement Linux on the named platform and make some tests to see if it is possible to replace OSE with Linux. Using Linux has several advantages, for example it is free of charge to use and over the years the popularity of Linux within the developer community has resulted in numerous tools and utilities available for free.</p><p>As a result, this study shows that Linux with real time extensions on the MPC8360 PowerPC platform is a viable alternative to OSE regarding cost efficiency, flexibility, adaptability and competence available on the market.</p><p>Further studies can be done towards benchmarking for I/O systems and implementing support for more hardware on the MPC8360 AF platform.</p>

<p>The goal of this project is to implement a system to analyse an audio signal containing speech, and produce a classifcation of lip shape categories (visemes) in order to synchronize the lips of a computer generated face with the speech. </p><p>The thesis describes the work to derive a method that maps speech to lip move- ments, on an animated face model, in real time. The method is implemented in C++ on the PC/Windows platform. The program reads speech from pre-recorded audio files and continuously performs spectral analysis of the speech. Neural networks are used to classify the speech into a sequence of phonemes, and the corresponding visemes are shown on the screen. </p><p>Some time delay between input speech and the visualization could not be avoided, but the overall visual impression is that sound and animation are synchronized.</p>

<p>The possibility to use real-time computer vision in video sequences gives many opportunities for a system to interact with the environment. Possible ways for interaction are e.g. augmented reality like in the MATRIS project where the purpose is to add new objects into the video sequence, or surveillance where the purpose is to find abnormal events.</p><p>The increase of the speed of computers the last years has simplified this process and it is now possible to use at least some of the more advanced computer vision algorithms that are available. The computational speed of computers is however still a problem, for an efficient real-time system efficient code and methods are necessary. This thesis deals with both problems, one part is about efficient implementations using single instruction multiple data (SIMD) instructions and one part is about robust tracking.</p><p>An efficient real-time system requires efficient implementations of the used computer vision methods. Efficient implementations requires knowledge about the CPU and the possibilities given. In this thesis, one method called SIMD is explained. SIMD is useful when the same operation is applied to multiple data which usually is the case in computer vision, the same operation is executed on each pixel.</p><p>Following the position of a feature or object in a video sequence is called tracking. Tracking can be used for a number of applications. The application in this thesis is to use tracking for pose estimation. One way to do tracking is to cut out a small region around the feature, creating a patch and find the position on this patch in the other frames. To find the position, a measure of the difference between the patch and the image in a given position is used. This thesis thoroughly investigates the sum of absolute difference (SAD) error measure. The investigation involves different ways to improve the robustness and to decrease the average error. One method to estimate the average error, the covariance of the position error is proposed. An estimate of the average error is needed when different measurements are combined.</p><p>Finally, a system for camera pose estimation is presented. The computer vision part of this system is based on the result in this thesis. This presentation contains also a discussion about the result of this system.</p> / Report code: LIU-TEK-LIC-2007:5. The report code in the thesis is incorrect.

<p>Many efforts have been carried out to provide transmission reliability in the history of communication systems. As the demand for real-time applications increased, providing a reliable communication in a timely manner for such applications is strongly desired. Considering timing constraints makes the issue of achieving reliability more difficult. This thesis concentrates on providing reliability for real-time communication in embedded networks by achieving a timing analysis and using the ARQ concept. What is carried out in this thesis is providing retransmission in a real-time manner for embedded networks according to application request. The thesis work focuses on one packet retransmission over a point to point link, but the concept is rich and can be extended to cover application request in real-time embedded networks. Two methods have been fulfilled, and a simulation has been done on the timing analysis focusing on the performance in accepting real-time traffic in the form of separate channels for each application request. The protocol combines ARQ and a scheduling algorithm as a base to support retransmission for hard real-time applications in embedded networks.</p>

<p>Ethernet technology is being accepted by industrial community due to its open standardization </p><p>and low cost. To meet the requirements of industrial applications, a switched Ethernet </p><p>network with hard real time guarantees using relative deadlines is presented as a first step to </p><p>verify the functionality. The goal of the project was primarily to implement a real-time </p><p>switched Ethernet with EDF (Earliest Deadline First) scheduling algorithm. </p><p>In this project, the function simulations of real-time switched Ethernet with distributed control </p><p>software have been implemented, by using a standard switch with priority-queues and the </p><p>distributed software, as well as EDF-scheduled TDMA (Time Division Medium Access). The </p><p>network topology is the star type. There is no extra hardware added into the switch and the </p><p>nodes. All functions are implemented by software and the setting in the switch. </p><p>The project focuses on hard real-time service guarantees but soft real-time traffic and non </p><p>real-time traffic, as well as real time administration are also taken into the consideration. </p><p>Our simulations show that 100 percent of the network usage could be scheduled and the result </p><p>of deterministic real-time properties of the system are achieved as expected.</p>

<p>Future parallel computer systems for embedded real-time applications,where each node in itself can be a parallel computer, are predicted to havevery high bandwidth demands on the interconnection network. Otherimportant properties are time-deterministic latency and guarantees to meetdeadlines. In this thesis, a fiber-optic passive optical star network with amedium access protocol for packet switched communication in distributedreal-time systems is proposed. By using WDM (Wavelength DivisionMultiplexing), multiple channels, each with a capacity of several Gb/s, areobtained.</p><p>A number of protocols for WDM star networks have recently been proposed.However, the area of real-time protocols for these networks is quiteunexplored. The protocol proposed in this thesis is based on TDMA (TimeDivision Multiple Access) and uses a new distributed slot-allocationalgorithm with real-time properties. Services for both guarantee-seekingmessages and best-effort messages are supported for single destination,multicast, and broadcast transmission. Slot reserving can be used toincrease the time-deterministic bandwidth, while still having an efficientbandwidth utilization due to a simple slot release method.</p><p>By connecting several clusters of the proposed WDM star network by abackbone star, thus forming a star-of-stars network, we get a modular andscalable high-bandwidth network. The deterministic properties of thenetwork are theoretically analyzed for both intra-cluster and inter-clustercommunication, and computer simulations of intra-cluster communicationare reported. Also, an overview of high-performance fiber-opticcommunication systems is presented.</p>

<p>High-performance embedded systems communicating heterogeneous traffic with high bandwidth and strict timing requirements are in need of more efficient communication solutions. This thesis proposes two multi-wavelength passive optical networks able to meet these demands. The networks are based upon a single-hop star topology with an Arrayed Waveguide Grating (AWG) placed in the centre. The intended application areas for the two networks are short range embedded communication systems like System Area Networks (SANs) and router architectures with electronic queuing. The AWG’s attractive property of spatial wavelength reuse, as well as the combination of fixed-tuned and tuneable transceivers in the end nodes, enables simultaneous control and data traffic transmission. This, in turn, makes it possible to support heterogeneous traffic with both hard and soft real-time constraints.</p><p>Additionally, two Medium Access Control (MAC) protocols, one for each network solution, are developed. Traffic scheduling is centrally controlled by a node, the protocol processor, residing together with the AWG in a hub. All nodes use Earliest Deadline First (EDF) scheduling and communicate with the protocol processor through physical control channels. A case study, including simulations, in the field of Radar Signal Processing (RSP) and simulations using periodic real-time traffic are conducted for the two application areas respectively, showing very good results. Further, a deterministic real-time analysis is conducted to provide throughput and delay guarantees for hard real-time traffic and an increase in guaranteed traffic is achieved through an analysis of existing traffic dependencies in a multichannel network. Simulation results incorporating the traffic dependency analysis indicate a considerable increase in the possible guaranteed throughput of hard real-time traffic.</p>

<p>Real-time networks are traditionally built on proprietary standards, resulting in a interoperability issues between different real-time netork implementations and traditional data networks mainly used in back office operations.</p><p>Continuity and supplier independence are a cause of concern with current</p><p>proprietary real-time networks.</p><p>This project evaluates the capability of providing real-time traffic over</p><p>switched Ethernet with EDF scheduling algorithm implemented at both the</p><p>switch and the node. By using OMNET simulation tool at packet level, it</p><p>is shown that the EDF implementation in switched Ethernet can guarantee</p><p>real-time traffic over the network and at the same time supporting non real-time traffic.</p>

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