Results 61 to 70 of about 3,066,783 (329)

The HVDC commutation failure mechanism impacted by harmonics and its suppression method

Frontiers in Energy Research
Harmonics are an important cause of voltage distortion, and voltage reduction and voltage distortion are the main causes of commutation failure. But most of the current research studies on commutation failure are based on the drop in fundamental voltage ...
Guojiang Zhang, Jingbo Zhao, Yongyong Jia, Qian Zhou, Ke Xu   +4 more
doaj   +1 more source

Charge-Spin Separation in 2D Fermi Systems: Singular Interactions as Modified Commutators, and Solution of 2D Hubbard Model in Bosonized Approximation [PDF]

, 1995
The general 2-dimensional fermion system with repulsive interactions (typified by the Hubbard Model) is bosonized, taking into account the finite on-shell forward scattering phase shift derived in earlier papers.
A. A. Abrikosov, A. El Azrak, A. Houghton, C. di Castro, D. G. Clarke, D. Khveshchenko, D. Khveshchenko, F. D. M. Haldane, F. D. M. Haldane, G. Engelbrecht, G. Engelbrecht, G. Engelbrecht, H. Fukuyama, H. Fukuyama, P. C. E. Stamp, P. W. Anderson, P. W. Anderson, P. W. Anderson   +17 more
core   +3 more sources

A pipeline crisis or a sustainability crisis? Local and national succession planning for headteachers in England

British Educational Research Journal, EarlyView.
Abstract Recruiting and retaining school leaders is a challenge in many systems worldwide. Previous research has identified three distinct ways in which succession planning can be conceptualised and approached: a ‘pipeline’ approach seeks to match supply and demand for the posts that need filling; a ‘pool’ strategy involves proactively identifying and ...
Toby Greany, Pat Thomson, Tom Perry, Mike Collins   +3 more
wiley   +1 more source

Commutation Failure Predictive Control Based on Fast AC Voltage Measurement in LCC-HVDC

IEEE Access, 2023
To inhibit commutation failure (CF), in this paper, the influence factors of CF were analyzed, and considering different fault types and different valves, the mathematical expression of extinction angle was deduced.
Guodong Huang, Xiao Tian, Haibo Yuan, Xiaofeng Dong, Li Zhou, Qing Wang   +5 more
doaj   +1 more source

HVDC System Commutation Failure Transient Judgement Method

DEStech Transactions on Engineering and Technology Research, 2019
In order to forecast the commutation failure of HVDC system, this paper analyzes the specific reasons for the rise of the direct current in the case of the receiving end failure of HVDC system and makes a quantitative analysis, It is found that the capacitance of direct transmission line discharging is the main factor of the increasing of the direct ...
Yong CUI, Mei-xia ZHANG, Ming-rui DONG, Jiang-yun YU, Wei-hong WANG, Liang CAO, Ming-jie JIN   +6 more
openaire   +2 more sources

Addressing racialised awarding gap in higher education: Insights from personal tutors

British Educational Research Journal, EarlyView.
Abstract Situated within a wider cross‐institutional research project, this article provides an in‐depth case study of one higher education (HE) institution, focusing on how personal tutors make sense of racialised degree awarding disparities for both undergraduate and postgraduate students, how they perceive their responsibilities, the challenges and ...
Benjamin Ajibade, Rick Hayman, Angela Hibbs, Josephine Gabi   +3 more
wiley   +1 more source

Symplectic Cuts and Projection Quantization [PDF]

, 1999
The recently proposed projection quantization, which is a method to quantize particular subspaces of systems with known quantum theory, is shown to yield a genuine quantization in several cases.
Echeverría-Enríquez A., Giulini D., MARTIN BOJOWALD, THOMAS STROBL, Woodhouse N. M. J.   +4 more
core   +4 more sources

From Two‐Electron to Four‐Electron System: Electrolyte Regulation for Advanced Aqueous Zn–I2 Batteries

Carbon Energy, EarlyView.
This review systematically summarizes recent progress in electrolyte‐regulated aqueous Zn–I2 batteries (AZIBs). It outlines the fundamentals of AZIBs along with their main challenges, and then analyzes electrolyte‐engineering strategies that improve both two‐ and four‐electron reactions.
Yucong Wang, Ruifeng Huang, Zhangchi Yang, Shaojian Zhang, Lijing Yan, Weijie Chen, Xiaolong Lin, Yongjun Li, Shuxing Wu, Zhan Lin, Jun Lu   +10 more
wiley   +1 more source

A review on evaluation and improvement methods for commutation failure resistance ability in multi-infeed direct current system

电力工程技术
The evaluation and improvement methods for commutation failure resistance ability in multi-infeed direct current (MIDC) system are of great significance for testing commutation failure characteristics, addressing assessment challenges, and applying ...
Yechun XIN, Taoyu HUANG, Tuo WANG, Yupeng HE, Xiaoluo GAN, Guoqing LI   +5 more
doaj   +1 more source

Poincare Algebra in Chiral QCD_2

, 1996
For the chiral QCD_2 on a cylinder, we give a construction of a quantum theory consistent with anomaly. We construct the algebra of the Poincare generators and show that it differs from the Poincare one.Comment: LATEX file, 10 ...
Carey, Faddeev, Faddeev, Fuad M. Saradzhev, Goddard, Grosse, Halliday, Jackiw, Jackiw, Langmann, Mickelsson, Nelson, Niemi, Paranjape, Rajaraman, Saradzhev, Saradzhev, Saradzhev   +17 more
core   +1 more source