685 research outputs found

    Low latency reconfiguration mechanism for fine-grained processor internal functional units

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    The strive for performance, low power consumption, and less chip area have been diminishing the reliability and the time to fault occurrences due to wear out of electronic devices. Recent research has shown that functional units within processors usually execute a different amount of operations when running programs. Therefore, these units present different individual wear out during their lifetime. Most existent schemes for re-configuration of processors due to fault detection and other processor parameters are done at the level of cores which is a costly way to achieve redundancy. This paper presents a low latency (approximately 1 clock cycle) software controlled mechanism to reconfigure units within processor cores according to predefined parameters. Such reconfiguration capability delivers features like wear out balance of processor functional units, configuration of units according to the criticality of tasks running on an operating system and configurations to gain in performance (e.g. parallel execution) when possible. The focus of this paper is to show the implemented low latency reconfiguration mechanism and highlight its possible main features

    Real-time dynamic hardware reconfiguration for processors with redundant functional units

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    The tiny logic elements in modern integrated circuits increase the rate of transient failures significantly. Therefore, redundancy on various levels is necessary to retain reliability. However, for mixed-criticality scenarios, the typical processor designs offer either too little fault-tolerance or too much redundancy for one part of the applications. Amongst others, we specifically address redundant processor internal functional units (FU) to cope with transient errors and support wear leveling. A real-time operating system (RTOS) was extended to control our prototypical hardware platform and, since it can be configured deterministically within few clock cycles, we are able to reconfigure the FUs dynamically, at process switching time, according to the specified critically of the running processes. Our mechanisms were integrated into the Plasma processor and the Plasma-RTOS. With few changes to the original software code, it was, for example, possible to quickly change from fault-detecting to fault-correcting modes of the processor on demand

    Integrated optics prototype beam combiner for long baseline interferometry in the L and M bands

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    In the last few years, integrated optics (IO) beam combiners have facilitated the emergence of 4-telescope interferometers such as PIONIER or GRAVITY, boosting the imaging capabilities of the VLTI. However, the spectral range beyond 2.2microns is not ideally covered by the conventional silica based IO. Here, we propose to consider new laser-written IO prototypes made of GLS glasses, a material that permits access to the mid-infrared spectral regime. Our goal is to conduct a full characterization of our mid-IR IO 2-telescope coupler in order to measure the performance levels directly relevant for long-baseline interferometry. We focus in particular on the exploitation of the L and M astronomical bands. We use a dedicated Michelson-interferometer setup to perform Fourier Transform spectroscopy on the coupler and measure its broadband interferometric performance. We also analyze the polarization properties of the coupler, the differential dispersion and phase degradation as well as the modal behavior and the total throughput. We measure broadband interferometric contrasts of 94.9% and 92.1% for unpolarized light in the L and M bands. Spectrally integrated splitting ratios are close to 50% but show chromatic dependence over the considered bandwidths. Additionally, the phase variation due to the combiner is measured and does not exceed 0.04rad and 0.07rad across the band L and M band, respectively. The total throughput of the coupler including Fresnel and injection losses from free-space is 25.4%. The laser-written IO GLS prototype combiners prove to be a reliable technological solution with promising performance for mid-infrared long-baseline interferometry. In the next steps, we will consider more advanced optical functions as well as a fiber-fed input and revise the optical design parameters in order the further enhance the total throughput and achromatic behavior

    Neverlast: Towards the Design and Implementation of the NVM-based Everlasting Operating System

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    Novel non-volatile memory (NVM) technologies allow for the efficient implementation of \u27\u27intermittently-powered\u27\u27 smart dust and edge computing systems in a previously unfamiliar way. Operating with rough environmental conditions where power-supply failures occur often requires adjustments to all parts of the system. This leads to an inevitable trade-off in the design of operating systems -- the overhead of persisting the achieved computation progress over power failures is detrimental to the possible amount of progress with the available energy budgets. It is, therefore, crucial to minimize the overhead of ensuring persistence. This paper presents the case that persistence should be provided as an operating-system service to achieve everlasting operating capabilities. Triggered by power-failure interrupts, an implicit persistence service for the processor status of a process preserves progress on the CPU-instruction level. This interrupt only triggers if necessary so that no power-state polling is needed. We outline architectures for everlasting systems and discuss their benefits and drawbacks compared to existing approaches. Thereby, the operating system provides persistence as a service at run-time to the application, with minimal overhead. Our approach enables the separation of the application from energy-supply state estimation, as well as state-preserving logic for software and hardware components

    Configurable Fault Tolerant Circuits and System Level Integration for Self-Awareness

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    Scaling minimum features of ICs down to the 10nm- area and below has allowed high integration rates in electronics. Scaling at supply voltages of 1V and below also implies a rising level of stress which drives aging effects that reduce switching speed and the expected life time. Additionally, vulnerability from particle radiation is increased. Hence, fault detection and on-line correction become a must for many applications. However, not only fault tolerance but self-awareness becomes also an advantage. Provided that by being aware of its own healthy state allow optimized configurations regarding system operation modes and configurable hardware mechanism. This paper shows a preliminary work in a configurable circuit and explores its configuration possibilities when integrated into a complete system

    Identification of single-point mutations in mycobacterial 16S rRNA sequences by confocal single-molecule fluorescence spectroscopy

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    We demonstrate the specific identification of single nucleotide polymorphism (SNP) responsible for rifampicin resistance of Mycobacterium tuberculosis applying fluorescently labeled DNA-hairpin structures (smart probes) in combination with single-molecule fluorescence spectroscopy. Smart probes are singly labeled hairpin-shaped oligonucleotides bearing a fluorescent dye at the 5′ end that is quenched by guanosine residues in the complementary stem. Upon hybridization to target sequences, a conformational change occurs, reflected in a strong increase in fluorescence intensity. An excess of unlabeled (‘cold’) oligonucleotides was used to prevent the formation of secondary structures in the target sequence and thus facilitates hybridization of smart probes. Applying standard ensemble fluorescence spectroscopy we demonstrate the identification of SNPs in PCR amplicons of mycobacterial rpoB gene fragments with a detection sensitivity of 10(−8) M. To increase the detection sensitivity, confocal fluorescence microscopy was used to observe fluorescence bursts of individual smart probes freely diffusing through the detection volume. By measuring burst size, burst duration and fluorescence lifetime for each fluorescence burst the discrimination accuracy between closed and open (hybridized) smart probes could be substantially increased. The developed technique enables the identification of SNPs in 10(−11) M solutions of PCR amplicons from M.tuberculosis in only 100 s

    Severe Wound Infection with Photobacterium damselae

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    Marine microorganisms are uncommon etiologies of skin and skin structure infections, that is, wound infections. We report a case of severe wound infection, caused by the marine Photobacterium damselae (Vibrionaceae), in a 64-year-old male patient, returning from Australia. The isolate tested positive for pPHDD1, a plasmid conferring high-level virulence. Furthermore, the wound was coinfected with Vibrio harveyi, a halophile bacterium, which has never been reported from human infections before. Identification was achieved by use of Matrix-Assisted Laser Desorption-Ionization Time of Flight Mass Spectrometry (MALDI-TOF) and confirmed by 16S rDNA sequencing. Data retrieval from bibliography was complicated since P. damselae has been renamed often with a number of synonyms present in the literature: Photobacterium damsela, Vibrio damselae, Vibrio damsela, Pasteurella damselae, and Listonella damsela. With all synonyms used as query terms, a literature search provided less than 20 cases published worldwide. A majority of those cases presenting as severe wound infection are even fatal following progression into necrotizing fasciitis. Management with daily wound dressing and antibiotic therapy (ofloxacin empirically, followed by doxycycline after availability of microbiology) led in the reported case to a favorable outcome, which seems to be, however, the exception based on a review of the available literature

    Регламентация бизнес-процессов организации с использованием Business Studio

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    В работе рассмотрены особенности применения графических методов моделирования в компании газовой отрасли для регламентации бизнес-процессов верхнего уровня. Разработана графическая модель отраслевого бизнес-процесса в системе Business Studio с использованием нотации IDEF0 и описан потенциал ее использования.The paper considers the features of using graphical modeling methods in the gas industry company for regulating top-level business processes. A graphical model of the industry-specific business process in the Business Studio system using IDEF0 notation is developed and the potential of its use is described
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