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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Adaptive CPU-budget allocation for soft-real-time applications

Ahmed, Safayet N. 27 August 2014 (has links)
The focus of this dissertation is adaptive CPU-budget allocation for periodic soft-real-time applications. The presented algorithms are developed in the context of a power-management framework. First, the prediction-based bandwidth scheduler (PBS) is developed. This algorithm is designed to adapt CPU-budget allocations at a faster rate than previous adaptive algorithms. Simulation results are presented to demonstrate that this approach allows for a faster response to under allocations than previous algorithms. A second algorithm is presented called Two-Stage Prediction (TSP) that improves on the PBS algorithm. Specifically, a more sophisticated algorithm is used to predict execution times and a stronger guarantee is provided on the timeliness of jobs. Implementation details and experimental results are presented for both the PBS and TSP algorithms. An abstraction is presented called virtual instruction count (VIC) to allow for more efficient budget allocation in power-managed systems. Power management decisions affect job-execution times. VIC is an abstract measure of computation that allows budget allocations to be made independent of power-management decisions. Implementation details and experimental results are presented for a VIC-based budget mechanism. Finally, a power-management framework is presented called the linear adaptive models based system (LAMbS). LAMbS is designed to minimize power consumption while honoring budget allocations specified in terms of VIC.
32

Execution time analysis for dynamic real-time systems

Zhou, Yongjun. January 2002 (has links)
Thesis (M.S.)--Ohio University, November, 2002. / Title from PDF t.p. Includes bibliographical references (leaves 101-103).
33

Optimal kernel development for real-time communications

Beltran, Monica G. 14 April 1994 (has links)
The purpose of this research is to develop an optimal kernel which would be used in a real-time engineering and communications system. Since the application is a real-time system, relevant real-time issues are studied in conjunction with kernel related issues. The emphasis of the research is the development of a kernel which would not only adhere to the criteria of a real-time environment, namely determinism and performance, but also provide the flexibility and portability associated with non-real-time environments. The essence of the research is to study how the features found in non-real-time systems could be applied to the real-time system in order to generate an optimal kernel which would provide flexibility and architecture independence while maintaining the performance needed by most of the engineering applications. Traditionally, development of real-time kernels has been done using assembly language. By utilizing the powerful constructs of the C language, a real-time kernel was developed which addressed the goals of flexibility and portability while still meeting the real-time criteria. The implementation of the kernel is carried out using the powerful 68010/20/30/40 microprocessor based systems.
34

Utility Accrual Real-time Channel Establishment in Multi-hop Networks

Channakeshava, Karthik 26 March 2004 (has links)
Real-time channels are established between a source and a destination to guarantee in-time delivery of real-time messages in multi-hop networks. In this thesis, we propose two schemes to establish real-time channels for soft real-time applications whose timeliness properties are characterized using Jensen's Time Utility Functions (TUFs) that are non-increasing. The two algorithms are (1) Localized Decision for Utility accrual Channel Establishment (LocDUCE) and (2) Global Decision for Utility accrual Channel Establishment (GloDUCE). Since finding a feasible path optimizing multiple constraints is an NP-Complete problem, these schemes heuristically attempt to maximize the system-wide accrued utility. The channel establishment algorithms assume the existence of a utility-aware packet scheduling algorithm at the interfaces. The route selection is based on delay estimation performed at the source, destination, and all routers in the path, from source to destination. We simulate the algorithms, measure and compare their performance with open shortest path first (OSPF). Our simulation experiments show that for most of the cases considered LocDUCE and GloDUCE perform better than OSPF. We also implement the schemes in a proof-of-concept style routing module and measure the performance of the schemes and compare them to OSPF. Our experiments on the implementation follow the same trend as the simulation study and show that LocDUCE and GloDUCE have a distinct advantage over OSPF and accrue higher system-wide utility. These schemes also react better to variation in the loading of the links. Among the two proposed approaches, we observe that GloDUCE performs better than LocDUCE under conditions of increased downstream link loads. / Master of Science
35

REAL-TIME TELEMETRY ON A PC

Smith, Dan, Steele, Doug 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Near real-time telemetry acquisition, processing and analysis on a desktop PC have always been difficult. Many factors complicate working with real-time data, including operating system latencies, design inefficiencies and hardware limitations. These problems are further compounded when data from multiple sources had to be integrated, increasing design complexity. Current design solutions for analyzing data in near real-time now utilize the latest hardware implementations and software designs, taking advantage of new hardware and language features. This paper will discuss several issues found with PC-based telemetry systems and how new designs are addressing these issues.
36

Highly variable real-time networks: an Ethernet/IP solution and application to railway trains

Constantopoulos, Vassilios 03 July 2006 (has links)
In this thesis we study the key requirements and solutions for the feasibility and application of Ethernet-TCP/IP technology to the networks we termed Highly-Variable Real-Time Networks (HVRN). This particular class of networks poses exceptionally demanding requirements because their physical and logical topologies are both temporally and spatially variable. We devised and introduced specific mechanisms for applying Ethernet-TCP/IP to HVRNs with particular emphasis on effective and reliable modular connectivity. Using a railroad train as a reference, this work analyzes the unique requirements of HVRNs and focuses on the backbone architecture for such a system under Ethernet and TCP/IP.
37

Petri nets approach for the analysis of MASCOT interprocess communications

Jiffry, Mustafa Abdulrahman January 2000 (has links)
No description available.
38

Fuzzy and multi-resolution data processing for advanced traffic and travel information

Agafonov, Evgeny January 2003 (has links)
No description available.
39

Open Architecture Telemetry Processing Systems

McMillen, Mark D. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / With the move toward design and interface standards in data acquisition and processing hardware and software, the development of open architecture telemetry processing systems has moved from a goal to a reality. The potential for a system to support hardware and software from a variety of vendors, allow inclusion of user-written software and user-provided interfaces, and provide a scalable, growth oriented processing capability can now be realized. This paper discusses the open architecture concept throughout the hardware and software components of the typical telemetry processing system. Utilizing such a system ensures flexibility to support different configurations, better and faster analysis through greater user programmability, and overall reduced costs by providing a system that can grow as future hardware and software components are brought to market.
40

Etablierung und Evaluierung eines Nachweisverfahrens klinisch relevanter Zygomyzeten anhand der Polymerasekettenreaktion / Development and Application of three independent PCR-Assays to detect clinically relevant Zygomycetes

Schmitt, Friderike January 2014 (has links) (PDF)
Invasive Zygomykosen verzeichnen in den letzten Jahren eine steigende Inzidenz, insbesondere im Risikokollektiv immunsupprimierter Patienten. Aufgrund des häufig letalen Verlaufs dieser Infektionen ist eine rasche, korrekte Diagnosestellung essentiell, um rechtzeitig eine adäquate Therapie einzuleiten. Jedoch sieht sich die konventionelle, mikrobiologische Diagnostik mit vielen Problemen konfrontiert, so dass molekularbiologische Nachweisverfahren zunehmend in den Fokus der Aufmerksamkeit rücken. Eine zuverlässige, mit relativ geringem Zeit- und Kostenaufwand praktizierbare Methode stellt in diesem Zusammenhang die Real-time-PCR dar, deren Aussagekraft durch anschließende Speziesidentifizierung mittels Sequenzierung noch verstärkt werden kann. Aus diesem Grund wurden im Rahmen dieser Arbeit 3 PCR-Assays entwickelt und deren Sensitivität, Spezifität und klinische Anwendbarkeit evaluiert. Alle 3 Systeme nutzten Multi-copy-Gene des ribosomalen Operons der Zygomyzeten als Target und erwiesen sich als zuverlässige Werkzeuge zur Amplifikation fungaler DNA. Sie wurde sowohl an Pilzkulturen, als auch an klinischen Proben und einem Quasi-Tiermodell mit Erfolg ausgetestet und werden möglicherweise in Zukunft der klinischen Routinediagnostik zur Verfügung stehen. Bedingt durch die Seltenheit invasiver Zygomykosen besteht in diesem Bereich noch ein großer Forschungsbedarf, auch, um die noch nicht optimale Therapie dieser Erkrankungen zu verbessern. Es bleibt daher zu hoffen, dass sich in absehbarer Zeit mehr Forschungsgruppen mit diesen Erregern beschäftigen, damit den schwer kranken Patienten eine echte Heilungschance geboten werden kann. / During the last years invasive zygomycosis register a rising incidence, in particular in the risk collective of immunosuppressed patients. On account of the often lethal course of these infections a fast, correct diagnosis is essential to initiate an adequate therapy on time. However, the conventional, microbiological diagnostics is confronted with many problems, so that molecular-biological methods to detect invasive mucormycosis get moor important. A reliable method requiring relatively low time is the real-time-PCR. The following sequencing of the amplicon allows the identification to the genus level. That's why 3 PCR-Assays were developed and their sensitivity, specificity and clinical applicability were evaluated. All 3 systems targeted multi copy genes of the ribosomal operon of the zygomycetes and turned out to be reliable tools for the amplification of fungal DNA. They were successfully tested in fungal cultures, as well as in clinical tests and a quasi animal model. In future they will possibly be available to the clinical routine diagnostics. Because of the rarity of invasive zycomycosis a lot of research is needed in this area, also to improve the therapy, frequently being insufficient. However, there remains hope that in future more research groups deal with these causes, so that a real healing chance can be offered to the seriously ill patients.

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