8,844 research outputs found

    Hydrodynamic scales of integrable many-particle systems

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    1. Introduction, 2. Dynamics of the classical Toda lattice, 3. Static properties, 4. Dyson Brownian motion. , 5. Hydrodynamics for hard rods, 6. Equations of generalized hydrodynamics, 7. Linearized hydrodynamics and GGE dynamical correlations, 8. Domain wall initial states, 9. Toda fluid, 10. Hydrodynamics of soliton gases, 11. Calogero models, 12. Discretized nonlinear Schr\"odinger equation , 13. Hydrodynamics for the Lieb-Liniger Ī“\delta-Bose gas, 14. Quantum Toda lattice, 15. Beyond the Euler time scaleComment: 178 pages, 12 Figures. This a much enlarged and substantially improved version of arXiv:2101.0652

    Design and development of a traction motor emulator using a three-phase bidirectional buck-boost AC-DC converter

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    An industrial drive testing, with a ???real-machine??? can pave way, for some serious issues to test-bench, motor, and the operator. A slight disturbance in control logic amid testing, can damage the physical machine or drive. Such dangerous testing conditions can be avoided by supplanting real motor with a power electronic converter based ???Motor Emulator??? (ME) test-bench system. The conventional ME comprises of two-stage three-phase AC-DC-AC conversion with first-stage AC-DC as emulator and second-stage DC-AC as regenerating unit. This two-stage power conversion, require independent control algorithm, burdening control complexity as well as the number of power electronic switches are quite significant. Therefore, to economize and downsize conventional multistage ME system, this research work experimentally validates a common-DC-bus-configured ME system with only the AC-DC regenerative emulator stage. A bidirectional three-phase AC-DC converter is proposed as the regenerative emulator converter in a common-DC-Bus-configured ME system. The Proposed converter???s operating principle along with mathematical design and control strategy are also presented. To validate the operation of the proposed converter as a common DC-bus-configured emulator, two permanent magnet synchronous motors (PMSM) of 7.5 kW and 2.0 kW are emulated and their simulation and experimental results are presented here. The proposed bi-directional converter inspired from classical buck-boost operation, requires just ten unidirectional IGBT switches preventing any circulating current in the system. The proposed converter also eliminates the regenerative converter stage in classical ME system. Also, the proposed common-DC-bus-configured ME system requires a single stage control unlike independent control in existing ME system. The proposed converter provides four-quadrant operation and emulation of motor under study. The dynamic model of PMSM motor is simulated on the MATLAB simulation platform and the Simulation results are compared with experimental results. From the simulation and experimental results, it is concluded that, with the presented control scheme, the proposed ME converter can be made to draw the same current as a real machine would have drawn, had it been driven by the same DUT. Since, the output current of proposed converter is fed back to DC bus, the input power source requirement is reduced, making the overall ME system more energy efficient

    Deciphering Regulation in Escherichia coli: From Genes to Genomes

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    Advances in DNA sequencing have revolutionized our ability to read genomes. However, even in the most well-studied of organisms, the bacterium Escherichia coli, for ā‰ˆ 65% of promoters we remain ignorant of their regulation. Until we crack this regulatory Rosetta Stone, efforts to read and write genomes will remain haphazard. We introduce a new method, Reg-Seq, that links massively-parallel reporter assays with mass spectrometry to produce a base pair resolution dissection of more than 100 E. coli promoters in 12 growth conditions. We demonstrate that the method recapitulates known regulatory information. Then, we examine regulatory architectures for more than 80 promoters which previously had no known regulatory information. In many cases, we also identify which transcription factors mediate their regulation. This method clears a path for highly multiplexed investigations of the regulatory genome of model organisms, with the potential of moving to an array of microbes of ecological and medical relevance.</p

    A Late Iron Age farmstead in the Outer Hebrides

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    The settlement at Bornais consists of a complex of mounds which protrude from the relatively flat machair plain in the township of Bornais on the island of South Uist. This sandy plain has proved an attractive settlement from the Beaker period onwards; it appears to have been intensively occupied from the Late Bronze Age to the end of the Norse period. Mound 1 was the original location for settlement in this part of the machair plain; pre-Viking activity of some complexity is present and it is likely that the settlement activity started in the Middle Iron Age, if not earlier. The examination of the mound 1 deposits provides an important contribution to our understanding of the Iron Age sequence in the Atlantic province. The principal contribution comprises the large quantities of mammal, fish and bird bones, carbonised plant remains and pottery, which can be accurately dated to a fairly precise and narrow period in the 1st millennium AD. These are augmented by a substantial collection of small finds which included distinctive bone artefacts. The contextual significance of the site is based on the survival of floor deposits and a burnt-down roof; the floor deposits can be compared with abandonment and adjacent midden deposits providing contrasting contextual environments that help to clarify depositional processes. The burning down of the house and the excellent preservation of the deposits within it provide an unparalleled opportunity to examine the timber superstructure of the building and the layout of the material used by the inhabitants

    Thermal-Hydraulics in Nuclear Fusion Technology: R&D and Applications

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    In nuclear fusion technology, thermal-hydraulics is a key discipline employed in the design phase of the systems and components to demonstrate performance, and to ensure the reliability and their efficient and economical operation. ITER is in charge of investigating the transients of the engineering systems; this included safety analysis. The thermal-hydraulics is required for the design and analysis of the cooling and ancillary systems such as the blanket, the divertor, the cryogenic, and the balance of plant systems, as well as the tritium carrier, extraction and recovery systems. This Special Issue collects and documents the recent scientific advancements which include, but are not limited to: thermal-hydraulic analyses of systems and components, including magneto-hydrodynamics; safety investigations of systems and components; numerical models and code development and application; codes coupling methodology; code assessment and validation, including benchmarks; experimental infrastructures design and operation; experimental campaigns and investigations; scaling issue in experiments

    Advanced Modeling and Research in Hybrid Microgrid Control and Optimization

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    This book presents the latest solutions in fuel cell (FC) and renewable energy implementation in mobile and stationary applications. The implementation of advanced energy management and optimization strategies are detailed for fuel cell and renewable microgrids, and for the multi-FC stack architecture of FC/electric vehicles to enhance the reliability of these systems and to reduce the costs related to energy production and maintenance. Cyber-security methods based on blockchain technology to increase the resilience of FC renewable hybrid microgrids are also presented. Therefore, this book is for all readers interested in these challenging directions of research

    Resource Recovery from Water

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    Throughout history, the first and foremost role of urban water management has been the protection of human health and the local aquatic environment. To this end, the practice of (waste-)water treatment has maintained a central focus on the removal of pollutants through dissipative pathways. Approaches like ā€“ in the case of wastewater treatment ā€“ the activated sludge process, which makes ā€˜hazardous thingsā€™ disappear, have benefitted our society tremendously by safeguarding human and environmental health. While conventional (waste-)water treatment is regarded as one of the greatest engineering achievements of the 20th century, these dissipative approaches will not suffice in the 21st century as we enter the era of the circular economy. A key challenge for the future of urban water management is the need to re-envision the role of water infrastructure, still holding paramount the safeguard of human and environmental health while also becoming a more proactive force for sustainable development through the recovery of resources embedded in urban water. This book aims (i) to explain the basic principles governing resource recovery from water (how much is there, really); (ii) to provide a comprehensive overview and critical assessment of the established and emerging technologies for resource recovery from water; and (iii) to put resource recovery from water in a legal, economic (including the economy of scale of recovered products), social (consumer's point of view), and environmental sustainability framework. This book serves as a powerful teaching tool at the graduate entry master level with an aim to help develop the next generation of engineers and experts and is also highly relevant for seasoned water professionals and practicing engineers

    Power Electronics Applications in Renewable Energy Systems

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    The renewable generation system is currently experiencing rapid growth in various power grids. The stability and dynamic response issues of power grids are receiving attention due to the increase in power electronics-based renewable energy. The main focus of this Special Issue is to provide solutions for power system planning and operation. Power electronics-based devices can offer new ancillary services to several industrial sectors. In order to fully include the capability of power conversion systems in the network integration of renewable generators, several studies should be carried out, including detailed studies of switching circuits, and comprehensive operating strategies for numerous devices, consisting of large-scale renewable generation clusters

    Convergence of Intelligent Data Acquisition and Advanced Computing Systems

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    This book is a collection of published articles from the Sensors Special Issue on "Convergence of Intelligent Data Acquisition and Advanced Computing Systems". It includes extended versions of the conference contributions from the 10th IEEE International Conference on Intelligent Data Acquisition and Advanced Computing Systems: Technology and Applications (IDAACSā€™2019), Metz, France, as well as external contributions

    Child Obesity and Nutrition Promotion Intervention

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    Childhood obesity continues to be a global problem, with several regions showing increasing rates and others having one in every three children overweight despite an apparent halt or downward trend. Children are exposed to nutritional, social, and obesogenic environmental risks from different settings, and this affects their lifelong health. There is a consensus that high-quality multifaceted smart and cost-effective interventions enable children to grow with a healthy set of habits that have lifelong benefits to their wellbeing. The literature has shown that dietary approaches play key roles in improving childrenā€™s health, not only on a nutritional level but also in diet quality and patterns. An association between the nutritional strategy and other lifestyle components promotes a more comprehensive approach and should be envisioned in intervention studies. This Special Issue entitled ā€œChild Obesity and Nutrition Promotion Interventionā€ combines original research manuscripts or reviews of the scientific literature concerning classic or innovative approaches to tackle this public health issue. It presents several nutritional interventions alongside lifestyle health factors, and outcome indicators of effectiveness and sustainability from traditional to ground-breaking methods to exploit both qualitative and quantitative approaches in tackling child obesity
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