2,045 research outputs found

    An Autonomic Cross-Platform Operating Environment for On-Demand Internet Computing

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    The Internet has evolved into a global and ubiquitous communication medium interconnecting powerful application servers, diverse desktop computers and mobile notebooks. Along with recent developments in computer technology, such as the convergence of computing and communication devices, the way how people use computers and the Internet has changed people´s working habits and has led to new application scenarios. On the one hand, pervasive computing, ubiquitous computing and nomadic computing become more and more important since different computing devices like PDAs and notebooks may be used concurrently and alternately, e.g. while the user is on the move. On the other hand, the ubiquitous availability and pervasive interconnection of computing systems have fostered various trends towards the dynamic utilization and spontaneous collaboration of available remote computing resources, which are addressed by approaches like utility computing, grid computing, cloud computing and public computing. From a general point of view, the common objective of this development is the use of Internet applications on demand, i.e. applications that are not installed in advance by a platform administrator but are dynamically deployed and run as they are requested by the application user. The heterogeneous and unmanaged nature of the Internet represents a major challenge for the on demand use of custom Internet applications across heterogeneous hardware platforms, operating systems and network environments. Promising remedies are autonomic computing systems that are supposed to maintain themselves without particular user or application intervention. In this thesis, an Autonomic Cross-Platform Operating Environment (ACOE) is presented that supports On Demand Internet Computing (ODIC), such as dynamic application composition and ad hoc execution migration. The approach is based on an integration middleware called crossware that does not replace existing middleware but operates as a self-managing mediator between diverse application requirements and heterogeneous platform configurations. A Java implementation of the Crossware Development Kit (XDK) is presented, followed by the description of the On Demand Internet Computing System (ODIX). The feasibility of the approach is shown by the implementation of an Internet Application Workbench, an Internet Application Factory and an Internet Peer Federation. They illustrate the use of ODIX to support local, remote and distributed ODIC, respectively. Finally, the suitability of the approach is discussed with respect to the support of ODIC

    Extending Cyber-Physical Systems to Support Stakeholder Decisions Under Resource and User Constraints: Applications to Intelligent Infrastructure and Social Urban Systems

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    In recent years, rapid urbanization has imposed greater load demands on physical infrastructure while placing stressors (e.g., pollution, congestion, social inequity) on social systems. Despite these challenges, opportunities are emerging from the unprecedented proliferation of information technologies enabling ubiquitous sensing, cloud computing, and full-scale automation. Together, these advancements enable “intelligent” systems that promise to enhance the operation of the built environment. Even with these advancements, the ability of professionals to “sense for decisions” —data-driven decision processes based on sensed data that have quantifiable returns on investment—remains unrealized for an entire class of problems. In response, this dissertation builds a rigorous foundation enabling stakeholders to use sensor data to inform decisions in two applications: infrastructure asset management and community-engaged decision making. This dissertation aligns sensing strategies with decisions governing infrastructure management by extending the role of reliability methods to quantify system performance. First, the reliability index is used as a scalar measure of the safety (i.e., failure probability) that is extracted from monitoring data to assess structural condition relative to a failure limit state. As an example, long-term data collected from a wireless sensing network (WSN) installed on the Harahan Bridge (Memphis, TN) is used in a reliability framework to track the fatigue life of critical eyebar assemblies. The proposed reliability-based SHM framework is then generalized to formally and more broadly link SHM data with condition ratings (CRs) because inspector-assigned CRs remain the primary starting point for asset management decisions made in practice today. While reliability methods historically quantify safety with respect to a single failure limit state, this work demonstrates that there exist measurable reliability index values associated with “lower” limit states below failure that more richly characterize structural performance and rationally map to CR scales. Consequently, monitoring data can be used to assign CRs based on quantitative information encompassing the measurable damage domain, as opposed to relying on visual inspection. This work reflects the first-ever SHM framework to explicitly map monitoring data to actionable decisions and is validated using a WSN on the Telegraph Road Bridge (TRB) (Monroe, MI). A primary challenge faced by solar-powered WSNs is their stringent energy constraints. For decision-making processes relying on statistical estimation of performance, the utility of data should be considered to optimize the data collection process given these constraints. This dissertation proposes a novel stochastic data collection and transmission policy for WSNs that minimizes the variance of a measured process’ estimated parameters subject to constraints imposed by energy and data buffer sizes, stochastic models of energy and event arrivals, the value of measured data, and temporal death. Numerical results based on one-year of data collected from the TRB illustrate the gains achieved by implementing the optimal policy to obtain response data used to estimate the reliability index. Finally, this dissertation extends the work performed in WSN and sense-for-decision frameworks by exploring their role in community-based decision making. This work poses societal engagement as a necessary entry point to urban sensing efforts because members of under-resourced communities are vulnerable to lack of access to data and information. A novel, low-power WSN architecture is presented that functions as a user-friendly sensing solution that communities can rapidly deploy. Applying this platform, transformative work to “democratize” data is proposed in which members of vulnerable communities collect data and generate insights that inform their decision-making strategies.PHDCivil EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/162898/1/kaflanig_1.pd

    Remote maintenance assistance using real-time augmented reality authoring

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    Maintenance operations and lifecycle engineering have largely been considered one of the most expensive and time-consuming components for industrial equipment. Numerous organizations continually devote large quantities of resources towards maintaining equipment. As such, any optimizations that would reduce maintenance errors and expenses could lead to substantial time and cost savings. Unfortunately, there are often not enough specialists to meet the demand, forcing localized technicians to perform on-site maintenance on equipment outside their area of expertise. Augmented reality (AR) is one technology that has already been shown to improve the maintenance process. While powerful, AR has its own set of challenges, from content authoring to spatial perception. This work details a system that puts both the power of AR and the knowledge of a specialist directly into the hands of an on-site technician. An application was developed that enables a specialist to deliver AR instructions in real-time to assist a technician performing on-site maintenance. Using a novel and simplified authoring interface, specialists can create AR content in real-time, with little to no prior knowledge of augmented reality or the system itself. There has been ample research on different AR-supported processes, such as real-time authoring, video monitoring, and off-site assistance. However, much less work has been done to integrate them and leverage existing personnel knowledge to both author and deliver real-time AR instructions. This work details the development and implementation of such a system. A technical evaluation was also performed to ensure real-time connectivity in geographically distributed environments. Three network configurations were evaluated. A high-latency high-bandwidth network was used to represent a typical modern maintenance facility. A low-bandwidth network was evaluated to mimic older or more isolated maintenance environments. Lastly, a 4G LTE network was tested, showing the potential for the system to be used across global locations. Under all network configurations, the system effectively facilitated the complete disassembly of a hydraulic pump assembly

    Déploiement continue des applications pervasives en milieux dynamiques

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    Driven by the emergence of new computing environments, dynamically evolving software systems makes it impossible for developers to deploy software with human-centric processes. Instead, there is an increasing need for automation tools that continuously deploy software into execution, in order to push updates or adapt existing software regarding contextual and business changes. Existing solutions fall short on providing fault-tolerant, reproducible deployments that would scale on heterogeneous environments. This thesis focuses especially on enabling continuous deployment solutions for dynamic execution platforms, such as would be found in Pervasive Computing environments. It adopts an approach based on a transactional, idempotent process for coordinating deployment actions. The thesis proposes a set of deployment tools, including a deployment manager capable of conducting deployments and continuously adapting applications according to the changes in the current state of the target platform. The implementation of these tools, Rondo, also allows developers and administrators to code application deployments thanks to a deployment descriptor DSL. Using the implementation of Rondo, the propositions of this thesis are validated in several industrial and academic projects by provisioning frameworks as well as on installing application and continuous reconfigurations.L'émergence des nouveaux types d'environnements informatiques amplifie le besoin pour des systèmes logiciels d'être capables d'évoluer dynamiquement. Cependant, ces systèmes rendent très difficile le déploiement de logiciels en utilisant des processus humains. Il y a donc un besoin croissant d'outils d'automatisation qui permettent de déployer et reconfigurer des systèmes logiciels sans en interrompre l'exécution. Le processus de déploiement continu et automatisé permet de mettre à jour ou d'adapter un logiciel en exécution en fonction des changements contextuels et des exigences opérationnelles. Les solutions existantes ne permettent pas des déploiements reproductibles et tolérant aux pannes dans des environnements fluctuants, et donc requérant une adaptation continue. Cette thèse se concentre en particulier sur des solutions de déploiement continu pour les plates-formes d'exécution dynamiques, tels que celle utilisé dans les environnements ubiquitaires. Elle adopte une approche basée sur un processus transactionnel et idempotent pour coordonner les actions de déploiement. La thèse propose, également, un ensemble d'outils, y compris un gestionnaire de déploiement capable de mener des déploiements discret, mais également d'adapter les applications continuellement en fonction des changements contextuels. La mise en œuvre de ces outils, permet notamment aux développeurs et aux administrateurs de développer des déploiements d'applications grâce à un langage spécifique suivant les principes de l‘infrastructure-as-code. En utilisant l'implantation de Rondo, les propositions de cette thèse sont validées dans plusieurs projets industriels et académiques à la fois pour l'administration de plates-formes ubiquitaires ainsi que pour l'installation d'applications et leurs reconfigurations continues

    Towards a Cyber-Physical Manufacturing Cloud through Operable Digital Twins and Virtual Production Lines

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    In last decade, the paradigm of Cyber-Physical Systems (CPS) has integrated industrial manufacturing systems with Cloud Computing technologies for Cloud Manufacturing. Up to 2015, there were many CPS-based manufacturing systems that collected real-time machining data to perform remote monitoring, prognostics and health management, and predictive maintenance. However, these CPS-integrated and network ready machines were not directly connected to the elements of Cloud Manufacturing and required human-in-the-loop. Addressing this gap, we introduced a new paradigm of Cyber-Physical Manufacturing Cloud (CPMC) that bridges a gap between physical machines and virtual space in 2017. CPMC virtualizes machine tools in cloud through web services for direct monitoring and operations through Internet. Fundamentally, CPMC differs with contemporary modern manufacturing paradigms. For instance, CPMC virtualizes machining tools in cloud using remote services and establish direct Internet-based communication, which is overlooked in existing Cloud Manufacturing systems. Another contemporary, namely cyber-physical production systems enable networked access to machining tools. Nevertheless, CPMC virtualizes manufacturing resources in cloud and monitor and operate them over the Internet. This dissertation defines the fundamental concepts of CPMC and expands its horizon in different aspects of cloud-based virtual manufacturing such as Digital Twins and Virtual Production Lines. Digital Twin (DT) is another evolving concept since 2002 that creates as-is replicas of machining tools in cyber space. Up to 2018, many researchers proposed state-of-the-art DTs, which only focused on monitoring production lifecycle management through simulations and data driven analytics. But they overlooked executing manufacturing processes through DTs from virtual space. This dissertation identifies that DTs can be made more productive if they engage directly in direct execution of manufacturing operations besides monitoring. Towards this novel approach, this dissertation proposes a new operable DT model of CPMC that inherits the features of direct monitoring and operations from cloud. This research envisages and opens the door for future manufacturing systems where resources are developed as cloud-based DTs for remote and distributed manufacturing. Proposed concepts and visions of DTs have spawned the following fundamental researches. This dissertation proposes a novel concept of DT based Virtual Production Lines (VPL) in CPMC in 2019. It presents a design of a service-oriented architecture of DTs that virtualizes physical manufacturing resources in CPMC. Proposed DT architecture offers a more compact and integral service-oriented virtual representations of manufacturing resources. To re-configure a VPL, one requirement is to establish DT-to-DT collaborations in manufacturing clouds, which replicates to concurrent resource-to-resource collaborations in shop floors. Satisfying the above requirements, this research designs a novel framework to easily re-configure, monitor and operate VPLs using DTs of CPMC. CPMC publishes individual web services for machining tools, which is a traditional approach in the domain of service computing. But this approach overcrowds service registry databases. This dissertation introduces a novel fundamental service publication and discovery approach in 2020, OpenDT, which publishes DTs with collections of services. Experimental results show easier discovery and remote access of DTs while re-configuring VPLs. Proposed researches in this dissertation have received numerous citations both from industry and academia, clearly proving impacts of research contributions

    Wireless Sensor Needs Defined by SBIR Topics

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    This slide presentation reviews the needs for wireless sensor technology from various U.S. government agencies as exhibited by an analysis of Small Business Innovation Research (SBIR) solicitations. It would appear that a multi-agency group looking at overlapping wireless sensor needs and technology projects is desired. Included in this presentation is a review of the NASA SBIR process, and an examination of some of the SBIR projects from NASA, and other agencies that involve wireless sensor developmen

    Intention-oriented programming support for runtime adaptive autonomic cloud-based applications

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    The continuing high rate of advances in information and communication systems technology creates many new commercial opportunities but also engenders a range of new technical challenges around maximising systems' dependability, availability, adaptability, and auditability. These challenges are under active research, with notable progress made in the support for dependable software design and management. Runtime support, however, is still in its infancy and requires further research. This paper focuses on a requirements model for the runtime execution and control of an intention-oriented Cloud-Based Application. Thus, a novel requirements modelling process referred to as Provision, Assurance and Auditing, and an associated framework are defined and developed where a given system's non/functional requirements are modelled in terms of intentions and encoded in a standard open mark-up language. An autonomic intention-oriented programming model, using the Neptune language, then handles its deployment and execution. © 2013 Elsevier Ltd. All rights reserved
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