25,255 research outputs found
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No full textIn this paper, we provide a formula for the vector space dimension of the ring over when all lie between successive powers of . For general , we provide a simple algorithm to calculate the vector space dimension of by combining our formula with certain results of Chungsim Han (1992).We edited the paper to reflect the fact that Theorem 1.2 of this paper follows from Theorem 3.8 in Han\u27s paper: The Hilbert-Kunz function of a diagonal hypersurface. We are grateful to Cheng Meng for bringing this to our attentio
Liver glucose transporter: a basolateral protein in hepatocytes and intestine and kidney cells
No full text Pages C279–C294: B. Thorens, Z.-Q. Cheng, D. Brown, and H. F. Lodish. “Liver glucose transporter: a basolateral protein in hepatocytes and intestine and kidney cells.” B. Thorens, H. F. Lodish, and D. Brown. “Differential localization of two glucose transporter isoforms in rat kidney.” Because of the disappointing reproduction of the halftones, these articles are reprinted at the end of the December issue. </jats:p
Liver glucose transporter: a basolateral protein in hepatocytes and intestine and kidney cells
No full text Pages C279–C294: B. Thorens, Z.-Q. Cheng, D. Brown, and H. F. Lodish. “Liver glucose transporter: a basolateral protein in hepatocytes and intestine and kidney cells.” B. Thorens, H. F. Lodish, and D. Brown. “Differential localization of two glucose transporter isoforms in rat kidney.” Because of the disappointing reproduction of the halftones, these articles are reprinted at the end of the December issue. </jats:p
Investigation on the wind preview quality for lidar-assisted wind turbine control under wake conditions
No full textThe wind preview provided by a nacelle-based lidar system allows the wind turbine controller to react to the wind disturbance prior to its impact on the turbine. This technology, commonly referred to as lidar-assisted wind turbine control, has been shown to be beneficial in reducing wind turbine structural loads. The wind preview quality defines how the lidar estimated disturbance is correlated with the actual one. In practice, the preview quality can vary following the change in atmospheric conditions and lidar operating states.When assessing the benefits of lidar-assisted control, previous studies mainly focused on the freestream turbulence where the turbine wake has not been included. In reality, wind turbines sometimes operate within the wake caused by upstream situated turbines, which happens more often in a narrowly spaced wind farm. Based on existing literature, the wake turbulence has three main phenomena compared with the freestream turbulence, i.e. (1) the reduced wind speed region (wake deficit), (2) the meandering (wake deficit moves in the lateral and vertical directions), and (3) the smaller-scale added turbulence caused by the interaction between rotor and the flow. The extent to which these phenomena affect the quality of lidar wind preview still needs to be investigated.In this paper, we use the dynamic wake meandering model, which covers the three wake characteristics mentioned above, and analyze its impact on lidar wind preview qualities. The most representative turbine layout where two turbines lie in a row will be considered. Frequency-domain analysis will be carried out to assess the measurement coherence of the lidar and the results will be compared to the freestream case
A Parameter-Exempted, High-Performance Power Decoupling Control of Single-Phase Electric Springs
No full textElectric Spring (ES) is an emerging technology intended to stabilize the voltage across the critical load (CL) of an end-user in the presence of fluctuations of the grid power. The most advanced way of controlling the so-called second generation of ES relies on the handling of both active and reactive power. However, the strategies used to implement such a control suffer from either the need of an a-priori knowledge of circuit parameters or a slow response to the grid power fluctuations. In this paper, a control strategy is proposed that overcomes these inconveniences. It relies on two problem-solving solutions, namely the closed-loop control of the dq components of the current drawn by the end-user and a feedback of the ES output current into the ES command. The setup of the proposed power decoupling control has just the features of being no affected by the circuit parameters and exhibiting an enhanced dynamic behavior. The features are validated by both simulation and experimental results
Reply to Dr. Jérôme Verine's Letter to the Editor re: Rodolfo Montironi, Marina Scarpelli, Liang Cheng, et al. Immunoglobulin G4-related Disease in Genitourinary Organs: An Emerging Fibroinflammatory Entity Often Misdiagnosed Preoperatively as Cancer.
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A type of piecewise and modular energy storage topology achieved by dual carrier cross phase shift SPWM control
No full textThis paper proposes a novel type of piecewise and modular energy storage topology. Compared to the modular multilevel converter (MMC), the proposed topology is not only different in structure but also in concept. Firstly, the capacitors within the submodules of MMC are all replaced by lithium batteries, which can avoid the voltage imbalance among capacitors and provide a deep connection between MMC and energy storage. What's more, the micro-unit concept is adopted to break the whole batteries within MMC into parts for each submodule by increasing the number of submodules to an extremely high level, which turns it into a novel microelement-based energy storage device. Due to the characteristics of the proposed topology, dual carrier cross-phase shift sinusoidal pulse width modulation (DCCPS-SPWM) is also proposed. With the help of DCCPS-SPWM, the proposed topology has the advantages of simple structure, easy to control, fewer total modules with the same output level, high fault tolerance, easy to detect and locate faults. The operating modes with four energy storage units per bridge arm are well analysed and extended to the case of N units. The double-Fourier analysis is performed on the output voltage waveform, so that the harmonics of the output voltage with DCCPS-SPWM can be clearly understood. Finally, the feasibility of the proposed topology and its control are verified by both simulation and experimental results
Suppressing influence of measurement noise on vibration-based damage detection involving higher-order derivatives
No full textAuthor name used in this publication: Cheng, Li.2012-2013 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishedPublisher permissio
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