7,231 research outputs found

    Real-time and fault tolerance in distributed control software

    Get PDF
    Closed loop control systems typically contain multitude of spatially distributed sensors and actuators operated simultaneously. So those systems are parallel and distributed in their essence. But mapping this parallelism onto the given distributed hardware architecture, brings in some additional requirements: safe multithreading, optimal process allocation, real-time scheduling of bus and network resources. Nowadays, fault tolerance methods and fast even online reconfiguration are becoming increasingly important. All those often conflicting requirements, make design and implementation of real-time distributed control systems an extremely difficult task, that requires substantial knowledge in several areas of control and computer science. Although many design methods have been proposed so far, none of them had succeeded to cover all important aspects of the problem at hand. [1] Continuous increase of production in embedded market, makes a simple and natural design methodology for real-time systems needed more then ever

    SANTO: Social Aerial NavigaTion in Outdoors

    Get PDF
    In recent years, the advances in remote connectivity, miniaturization of electronic components and computing power has led to the integration of these technologies in daily devices like cars or aerial vehicles. From these, a consumer-grade option that has gained popularity are the drones or unmanned aerial vehicles, namely quadrotors. Although until recently they have not been used for commercial applications, their inherent potential for a number of tasks where small and intelligent devices are needed is huge. However, although the integrated hardware has advanced exponentially, the refinement of software used for these applications has not beet yet exploited enough. Recently, this shift is visible in the improvement of common tasks in the field of robotics, such as object tracking or autonomous navigation. Moreover, these challenges can become bigger when taking into account the dynamic nature of the real world, where the insight about the current environment is constantly changing. These settings are considered in the improvement of robot-human interaction, where the potential use of these devices is clear, and algorithms are being developed to improve this situation. By the use of the latest advances in artificial intelligence, the human brain behavior is simulated by the so-called neural networks, in such a way that computing system performs as similar as possible as the human behavior. To this end, the system does learn by error which, in an akin way to the human learning, requires a set of previous experiences quite considerable, in order for the algorithm to retain the manners. Applying these technologies to robot-human interaction do narrow the gap. Even so, from a bird's eye, a noticeable time slot used for the application of these technologies is required for the curation of a high-quality dataset, in order to ensure that the learning process is optimal and no wrong actions are retained. Therefore, it is essential to have a development platform in place to ensure these principles are enforced throughout the whole process of creation and optimization of the algorithm. In this work, multiple already-existing handicaps found in pipelines of this computational gauge are exposed, approaching each of them in a independent and simple manner, in such a way that the solutions proposed can be leveraged by the maximum number of workflows. On one side, this project concentrates on reducing the number of bugs introduced by flawed data, as to help the researchers to focus on developing more sophisticated models. On the other side, the shortage of integrated development systems for this kind of pipelines is envisaged, and with special care those using simulated or controlled environments, with the goal of easing the continuous iteration of these pipelines.Thanks to the increasing popularity of drones, the research and development of autonomous capibilities has become easier. However, due to the challenge of integrating multiple technologies, the available software stack to engage this task is restricted. In this thesis, we accent the divergencies among unmanned-aerial-vehicle simulators and propose a platform to allow faster and in-depth prototyping of machine learning algorithms for this drones

    What May Visualization Processes Optimize?

    Full text link
    In this paper, we present an abstract model of visualization and inference processes and describe an information-theoretic measure for optimizing such processes. In order to obtain such an abstraction, we first examined six classes of workflows in data analysis and visualization, and identified four levels of typical visualization components, namely disseminative, observational, analytical and model-developmental visualization. We noticed a common phenomenon at different levels of visualization, that is, the transformation of data spaces (referred to as alphabets) usually corresponds to the reduction of maximal entropy along a workflow. Based on this observation, we establish an information-theoretic measure of cost-benefit ratio that may be used as a cost function for optimizing a data visualization process. To demonstrate the validity of this measure, we examined a number of successful visualization processes in the literature, and showed that the information-theoretic measure can mathematically explain the advantages of such processes over possible alternatives.Comment: 10 page

    Mikropalveluiden testauskÀytÀnnöt julkisen sektorin projekteissa

    Get PDF
    Online services are constantly evolving, which makes service maintainability challenging. This has led to micro service architecture, where big applications are split into smaller services in order to improve applications' maintainability, scalability, and flexibility. However, splitting a single process application into multiple services causes the testing process to be more challenging. This Master's thesis is exploring these testing problems in a micro service context and finding practical guidance for the test implementation. Moreover, this Master's thesis focuses on public sector software projects. Public sector software projects are clearly predefined and the provider has open information about the project's needs. Thus, the project has a clear goal and known boundaries right from the beginning. The research approach for this study is an exploratory multiple case study consisting of three case projects. The data of the case projects were collected through semi-structural interviews and version history commit analysis. The results of this study present a set of successful practices and recommendations for taking testing into account during a micro service oriented agile development process. Successful testing requires monitoring of the project's maturity level to focus testing resources at the right time. Additionally, the case projects brought up practical testing guidance, such as understanding of the common testing responsibility, the importance of peer review, and the value of assigning a specific tester after the project has reached its end-to-end testing phase.Web-palvelut kehittyvÀt jatkuvasti, mikÀ vaikeuttaa palveluiden yllÀpitoa. YhtenÀ ratkaisuna on palvelun pilkkominen osiin mikropalveluiksi. Palvelun pilkkominen edistÀÀ palvelun yllÀpitoa, skaalattavuutta ja joustavuutta. Toisaalta palvelun pilkkominen mikropalveluiksi vaikeuttaa testausprosessia. TÀmÀ diplomityö tutkii mikropalveluiden testausprosessiin liittyviÀ ongelmia ja etsii kÀytÀnnönlÀheistÀ ohjeistuista testien toteuttamiseen mikropalveluympÀristössÀ. Diplomityö keskittyy julkisen sektorin mikropalveluprojekteihin, koska kaikki tÀssÀ diplomityössÀ kÀytetyt tutkimusprojektit ovat julkisen sektorin hallinnoimia. Julkisen sektorin ohjelmistoprojektit ovat selkeÀsti esimÀÀriteltyjÀ ja projektien aineisto on avoimesti saatavilla. TÀmÀn takia projekteilla on selkeÀ pÀÀmÀÀrÀ ja tunnetut rajat heti projektin alussa. TutkimusmenetelmÀnÀ kÀytettiin tutkivaa case study -menetelmÀÀ. Tutkimus sisÀlsi kolme tutkimuskohdetta. Tutkimusdata kerÀttiin osittain jÀsennetyillÀ kontekstuaalisilla haastatteluilla ja ohjelmistokoodin versiohallinnan historian analyysillÀ. Tuloksena syntyi kokoelma hyvÀksi todettuja kÀytÀntöjÀ ja suosituksia, jotka auttavat ottamaan testauksen huomioon mikropalvelun iteratiivisessa ohjelmistokehitysprosessissa. Suositeltaviksi testauskÀytÀnnöiksi havaittiin projektin maturiteetin tarkkaileminen, ettÀ testauksen resursointi voidaan tehdÀ oikeaan aikaan. LisÀksi, projekteista nousi esiin muita suosituksia, kuten kehitystiimin yhteisen testaamisvastuun ymmÀrtÀminen, koodikatselmoinnin merkitys ja erillisen testaajan tÀrkeys, kun projektin maturiteetti on kasvanut riittÀvÀsti

    The Semantic Grid: A future e-Science infrastructure

    No full text
    e-Science offers a promising vision of how computer and communication technology can support and enhance the scientific process. It does this by enabling scientists to generate, analyse, share and discuss their insights, experiments and results in an effective manner. The underlying computer infrastructure that provides these facilities is commonly referred to as the Grid. At this time, there are a number of grid applications being developed and there is a whole raft of computer technologies that provide fragments of the necessary functionality. However there is currently a major gap between these endeavours and the vision of e-Science in which there is a high degree of easy-to-use and seamless automation and in which there are flexible collaborations and computations on a global scale. To bridge this practice–aspiration divide, this paper presents a research agenda whose aim is to move from the current state of the art in e-Science infrastructure, to the future infrastructure that is needed to support the full richness of the e-Science vision. Here the future e-Science research infrastructure is termed the Semantic Grid (Semantic Grid to Grid is meant to connote a similar relationship to the one that exists between the Semantic Web and the Web). In particular, we present a conceptual architecture for the Semantic Grid. This architecture adopts a service-oriented perspective in which distinct stakeholders in the scientific process, represented as software agents, provide services to one another, under various service level agreements, in various forms of marketplace. We then focus predominantly on the issues concerned with the way that knowledge is acquired and used in such environments since we believe this is the key differentiator between current grid endeavours and those envisioned for the Semantic Grid

    Configurable nD-visualization for complex Building Information Models

    Get PDF
    With the ongoing development of building information modelling (BIM) towards a comprehensive coverage of all construction project information in a semantically explicit way, visual representations became decoupled from the building information models. While traditional construction drawings implicitly contained the visual representation besides the information, nowadays they are generated on the fly, hard-coded in software applications dedicated to other tasks such as analysis, simulation, structural design or communication. Due to the abstract nature of information models and the increasing amount of digital information captured during construction projects, visual representations are essential for humans in order to access the information, to understand it, and to engage with it. At the same time digital media open up the new field of interactive visualizations. The full potential of BIM can only be unlocked with customized task-specific visualizations, with engineers and architects actively involved in the design and development process of these visualizations. The visualizations must be reusable and reliably reproducible during communication processes. Further, to support creative problem solving, it must be possible to modify and refine them. This thesis aims at reconnecting building information models and their visual representations: on a theoretic level, on the level of methods and in terms of tool support. First, the research seeks to improve the knowledge about visualization generation in conjunction with current BIM developments such as the multimodel. The approach is based on the reference model of the visualization pipeline and addresses structural as well as quantitative aspects of the visualization generation. Second, based on the theoretic foundation, a method is derived to construct visual representations from given visualization specifications. To this end, the idea of a domain-specific language (DSL) is employed. Finally, a software prototype proofs the concept. Using the visualization framework, visual representations can be generated from a specific building information model and a specific visualization description.Mit der fortschreitenden Entwicklung des Building Information Modelling (BIM) hin zu einer umfassenden Erfassung aller Bauprojektinformationen in einer semantisch expliziten Weise werden Visualisierungen von den GebĂ€udeinformationen entkoppelt. WĂ€hrend traditionelle Architektur- und Bauzeichnungen die visuellen ReprĂ€Ìˆsentationen implizit als TrĂ€ger der Informationen enthalten, werden sie heute on-the-fly generiert. Die Details ihrer Generierung sind festgeschrieben in Softwareanwendungen, welche eigentlich fĂŒr andere Aufgaben wie Analyse, Simulation, Entwurf oder Kommunikation ausgelegt sind. Angesichts der abstrakten Natur von Informationsmodellen und der steigenden Menge digitaler Informationen, die im Verlauf von Bauprojekten erfasst werden, sind visuelle ReprĂ€sentationen essentiell, um sich die Information erschließen, sie verstehen, durchdringen und mit ihnen arbeiten zu können. Gleichzeitig entwickelt sich durch die digitalen Medien eine neues Feld der interaktiven Visualisierungen. Das volle Potential von BIM kann nur mit angepassten aufgabenspezifischen Visualisierungen erschlossen werden, bei denen Ingenieur*innen und Architekt*innen aktiv in den Entwurf und die Entwicklung dieser Visualisierungen einbezogen werden. Die Visualisierungen mĂŒssen wiederverwendbar sein und in Kommunikationsprozessen zuverlĂ€ssig reproduziert werden können. Außerdem muss es möglich sein, Visualisierungen zu modifizieren und neu zu definieren, um das kreative Problemlösen zu unterstĂŒtzen. Die vorliegende Arbeit zielt darauf ab, GebĂ€udemodelle und ihre visuellen ReprĂ€sentationen wieder zu verbinden: auf der theoretischen Ebene, auf der Ebene der Methoden und hinsichtlich der unterstĂŒtzenden Werkzeuge. Auf der theoretischen Ebene trĂ€gt die Arbeit zunĂ€chst dazu bei, das Wissen um die Erstellung von Visualisierungen im Kontext von Bauprojekten zu erweitern. Der verfolgte Ansatz basiert auf dem Referenzmodell der Visualisierungspipeline und geht dabei sowohl auf strukturelle als auch auf quantitative Aspekte des Visualisierungsprozesses ein. Zweitens wird eine Methode entwickelt, die visuelle ReprĂ€sentationen auf Basis gegebener Visualisierungsspezifikationen generieren kann. Schließlich belegt ein Softwareprototyp die Realisierbarkeit des Konzepts. Mit dem entwickelten Framework können visuelle ReprĂ€sentationen aus jeweils einem spezifischen GebĂ€udemodell und einer spezifischen Visualisierungsbeschreibung generiert werden
    • 

    corecore