59 research outputs found

    AUV NILM Update

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    Work on the AUV NILM project has proceeded along two main fronts: (1) NILM System Development; (2) Diagnostics for Li-Ion Batterie

    Conserving Energy with No Watt Left Behind

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    Facilities managers for industrial and commercial sites want to develop detailed electrical consumption profiles of their electrical and electromechanical loads, including expensive physical plant for heating, ventilation, and air conditioning (HVAC) and equipment for manufacturing and production. This information is essential in order to understand and optimize energy consumption, to detect and solve equipment failures and problems, and to facilitate predictive maintenance of electromechanical loads. As energy costs rise, residential customers are also developing a growing interest in understanding the magnitude and impact of their electrical consumption quickly, easily, and informatively

    Scalability of Non-intrusive Load Monitoring for Shipboard Applications

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    The non-intrusive load monitor has been demonstrated as an effective tool for evaluating and monitoring shipboard electro-mechanical systems through analysis of electrical power data. A key advantage of the non-intrusive approach is the ability to reduce sensor count by monitoring collections of loads. This paper reviews trade-offs that affect the likely performance of the NILM in a real world environment.Massachusetts Institute of Technology. Sea Grant College Program; Grainger Foundation; National Science Foundation (U.S.); United States. National Aeronautics and Space Administration; United States. Coast Guard; United States. Office of Naval Research. Electric Ship Research and Development Consortium; NAVSEA; University of North Carolin

    A Hands-On Approach to Advanced Undergraduate Instruction in Control and Circuitry in Power Electronics

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    We have developed a hands-on kit to teach control and circuits in power electronics. The kit consists of only discrete components to improve on what is missing from the contemporary IC design experience: the insight and intuition that arises from the building and testing of circuits where there is physical access to every node. The kit is modular and configurable, allowing students to explore the design space with different topologies and component values, while trading-off bandwidth, power, and accuracy, among other things.MIT Center for Materials Science and Engineering, a Materials Research Science and Engineering Center funded by the National Science Foundation under award number DMR 02-13282.Grainger FoundationPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137655/1/PEEW-03 2007.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137655/2/PEEW-03 2007.pdfDescription of PEEW-03 2007.pdf : Main ArticleDescription of PEEW-03 2007.pdf : Main Article PDF/

    How Much DC Power Is Necessary?

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    Many proposals for future power systems for warships are extant. Anticipated improvements in capability, operating economy, and signature reduction may not be uniquely associated with these power systems. Alternatives are available for constructing variable speed drives and prime movers for ships with electric drives. These alternatives may open new design possibilities

    Field Demonstration of a Real-time Non-intrusive Monitoring System for Condition-based Maintenance

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    The performance of important electrical loads on mission critical systems like warships or off-shore platforms is often tracked by dedicated monitoring equipment. Individual monitoring of each load is expensive and risky. Expense occurs because of the need for individual sensors and sensor wiring for every load of interest. Reliability is compromised because detected failures or fault conditions might legitimately be due to load failure, but might also be due to errors or failure in the sensor network or recording instruments. The power distribution network on a warship could be pressed into “dual-use” service, providing not only power distribution but also a diagnostic monitoring capability based on observations of the way in which loads draw power from the distribution service. This paper describes field tests of a prototype system that monitors multiple loads using existing electrical wiring. Initial results are presented from a device that monitors a small collection of motors and two other devices that monitor an entire engine room.Grainger Foundation; National Science Foundation (U.S.); United States. National Aeronautics and Space Administration; United States. Coast Guard; United States. Office of Naval Research. Electric Ship Research and Development Consortium; NAVSEA; University of North Carolin

    Custom Integrated Circuits

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    Contains reports on ten research projects.Analog Devices, Inc.IBM CorporationNational Science Foundation/Defense Advanced Research Projects Agency Grant MIP 88-14612Analog Devices Career Development Assistant ProfessorshipU.S. Navy - Office of Naval Research Contract N0014-87-K-0825AT&TDigital Equipment CorporationNational Science Foundation Grant MIP 88-5876

    Retrotransposon-Induced Heterochromatin Spreading in the Mouse Revealed by Insertional Polymorphisms

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    The “arms race” relationship between transposable elements (TEs) and their host has promoted a series of epigenetic silencing mechanisms directed against TEs. Retrotransposons, a class of TEs, are often located in repressed regions and are thought to induce heterochromatin formation and spreading. However, direct evidence for TE–induced local heterochromatin in mammals is surprisingly scarce. To examine this phenomenon, we chose two mouse embryonic stem (ES) cell lines that possess insertionally polymorphic retrotransposons (IAP, ETn/MusD, and LINE elements) at specific loci in one cell line but not the other. Employing ChIP-seq data for these cell lines, we show that IAP elements robustly induce H3K9me3 and H4K20me3 marks in flanking genomic DNA. In contrast, such heterochromatin is not induced by LINE copies and only by a minority of polymorphic ETn/MusD copies. DNA methylation is independent of the presence of IAP copies, since it is present in flanking regions of both full and empty sites. Finally, such spreading into genes appears to be rare, since the transcriptional start sites of very few genes are less than one Kb from an IAP. However, the B3galtl gene is subject to transcriptional silencing via IAP-induced heterochromatin. Hence, although rare, IAP-induced local heterochromatin spreading into nearby genes may influence expression and, in turn, host fitness

    The neutron and its role in cosmology and particle physics

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    Experiments with cold and ultracold neutrons have reached a level of precision such that problems far beyond the scale of the present Standard Model of particle physics become accessible to experimental investigation. Due to the close links between particle physics and cosmology, these studies also permit a deep look into the very first instances of our universe. First addressed in this article, both in theory and experiment, is the problem of baryogenesis ... The question how baryogenesis could have happened is open to experimental tests, and it turns out that this problem can be curbed by the very stringent limits on an electric dipole moment of the neutron, a quantity that also has deep implications for particle physics. Then we discuss the recent spectacular observation of neutron quantization in the earth's gravitational field and of resonance transitions between such gravitational energy states. These measurements, together with new evaluations of neutron scattering data, set new constraints on deviations from Newton's gravitational law at the picometer scale. Such deviations are predicted in modern theories with extra-dimensions that propose unification of the Planck scale with the scale of the Standard Model ... Another main topic is the weak-interaction parameters in various fields of physics and astrophysics that must all be derived from measured neutron decay data. Up to now, about 10 different neutron decay observables have been measured, much more than needed in the electroweak Standard Model. This allows various precise tests for new physics beyond the Standard Model, competing with or surpassing similar tests at high-energy. The review ends with a discussion of neutron and nuclear data required in the synthesis of the elements during the "first three minutes" and later on in stellar nucleosynthesis.Comment: 91 pages, 30 figures, accepted by Reviews of Modern Physic
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