Results 71 to 80 of about 142,195 (311)

Study on fault ride-through control of islanded wind farm connected to VSC-HVDC grid based on the VSC converter AC-side bus forced short circuit

The Journal of Engineering, 2019
Wind farms integrated to an AC power system through a voltage source converter-based high-voltage direct current system (VSC-HVDC) are viewed as islanded wind farms. The wind farm side converter of VSC-HVDC maintains a constant frequency of the wind farm
Yan Li, Chao Liu, Xinshou Tian, Zhibing Wang   +3 more
doaj   +1 more source

Relationship Between Knowledge and Compliance With Safety Measures: Evidence From COVID‐19

Applied Economic Perspectives and Policy, EarlyView.
ABSTRACT Compliance with health safety protocols is important for protecting public health, particularly in agricultural sectors where disease outbreaks can disrupt production and market access. Despite its economic significance, we know little about what drives protocol compliance.
Nilufer Cetik, Carola Grebitus, Lauren Chenarides   +2 more
wiley   +1 more source

A DC fault ride-through and energy dissipation scheme for hybrid MMC-MTDC integrating wind farms with overhead lines

The Journal of Engineering, 2019
To integrate bulk wind power, using modular multilevel converter (MMC) based DC grids is an effective solution to improve the flexibility and reliability of the power grid.
Shuai Cao, Wang Xiang, Xiaojun Lu, Weixing Ling, Jinyu Wen   +4 more
doaj   +1 more source

Modified half-bridge modular multilevel converter for HVDC systems with DC fault ride-through capability [PDF]

, 2014
One of the main challenges of voltage source converter based HVDC systems is DC faults. In this paper, two different modified half-bridge modular multilevel converter topologies are proposed.
Aboushady, A.A., Ahmed, K.H.
core   +2 more sources

Upsampling DINOv2 Features for Unsupervised Vision Tasks and Weakly Supervised Materials Segmentation

Advanced Intelligent Systems, EarlyView.
Feature from recent image foundation models (DINOv2) are useful for vision tasks (segmentation, object localization) with little or no human input. Once upsampled, they can be used for weakly supervised micrograph segmentation, achieving strong results when compared to classical features (blurs, edge detection) across a range of material systems.
Ronan Docherty, Antonis Vamvakeros, Samuel J. Cooper   +2 more
wiley   +1 more source

Pre-charging and DC fault ride-through of hybrid MMC based HVDC systems [PDF]

, 2015
Compared to half-bridge based MMCs, full-bridge based systems have the advantage of blocking dc fault, but at the expense of increased power semiconductors and power losses.
Morrow, D John, Xu, Lie, Yao, Liangzhong, Zeng, Rong   +3 more
core   +1 more source

Structural problems without structural solutions? Youth leaders' perceptions of their community

American Journal of Community Psychology, EarlyView.
Abstract As young people explore and reflect on the conditions of their neighborhoods and communities, they can forge a critical consciousness—merging their perspectives and analysis to direct both individual and collective actions. Photovoice is a methodological tool that allows participants to document their perspectives and analysis and discuss with
Linnea L. Hjelm, Aishia A. Brown, Benjamin W. Fisher, Alice Story, Nubia Bennett   +4 more
wiley   +1 more source

A lightweight MMC topology with recombined half‐bridge submodules for DC fault ride‐through

IET Generation, Transmission & Distribution
The lightweight of modular multilevel converter (MMC) and the DC faults ride‐through ability are main challenges for MMC‐high voltage direct current (HVDC) transmission systems.
Yutao Xu, Zhukui Tan, Jikai Li, Qihui Feng, Zhuang Wu   +4 more
doaj   +1 more source

A hybrid modular multilevel converter with novel three-level cells for DC fault blocking capability [PDF]

, 2015
A novel hybrid, modular multilevel converter is presented that utilizes a combination of half-bridge and novel three-level cells where the three-level cells utilize a clamp circuit which, under dc side faults, is capable of blocking fault current thereby
Fletcher, John E., Holliday, Derrick, Li, Rui, Williams, Barry W., Xu, Lie   +4 more
core   +1 more source

Neighborhood social environments and mental health among youth and adults in public housing

American Journal of Community Psychology, EarlyView.
Abstract Neighborhoods influence health in part through social processes. However, little is known about how multiple neighborhood social processes co‐occur, or about within (vs. between) neighborhood variation in social processes and health. This study asked how residents of a large public housing development describe their neighborhood and used ...
Jane Leer, Lindsay Lanteri, Rebekah Levine Coley, Samantha Teixeira   +3 more
wiley   +1 more source