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A Scenario-classification Hybrid-based Banding Method for Power Transfer Limits of Critical Inter-corridors

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 547-560页

作者： Lidong yi Maosheng Ding Jili Wang Gao Qiu fei Xue Ji'ang Liu Yuxiong huang Gengfeng Li Junyong Liu State Grid Ningxia Electric Power Co. Ltd.YinchuanChinaand M.Ding is also with State Grid Ningxia Electric Power Research InstituteYinchuanChina Northwest Branch State Grid Corporation of ChinaXi’anChina School of Electrical Engineering Sichuan UniversityChengduChina State Grid Ningxia Electric Power Research Institute yinchuan YinchuanChina School of Electrical Engineering Xi’an Jiaotong UniversityXi’anChina IEEE

To secure power system operations,practical dispatches in industries place a steady power transfer limit on critical inter-corridors,rather than high-dimensional and strong nonlinear stability ***,computational complexities lead to over-conservative pre-settings of transfer limit,which further induce undesirable and non-technical congestion of power *** conquer this barrier,a scenario-classification hybrid-based banding method is proposed.A cluster technique is adopted to separate similarities from historical and generated operating condition *** a practical rule,transfer limits are approximated for each operating ***,toward an interpretable online transfer limit decision,costsensitive learning is applied to identify cluster affiliation to assign a transfer limit for a given *** this stage,critical variables that affect the transfer limit are also picked out via mean impact *** enables us to construct low-complexity and dispatcher-friendly rules for fast determination of transfer *** numerical case studies on the IEEE 39-bus system and a real-world regional power system in China illustrate the effectiveness and conservativeness of the proposed method.

关键词： Transfer limit transfer capability power transfer inter-corridor cluster cost-sensitive learning banding power system operation

Accuracy of segmented measurement of axial length in ultra-high myopia filled with silicone oil using immersion B-scan ultrasonography

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International Journal of Ophthalmology(English edition) 2022年第5期15卷 793-799页

作者： Qing-Hua Yang Hong-Tao Zhang Xiao-Qi Li Bing Chen Zhao-Hui Li yi-fei huang Xin Jin ying Zhang Li-Qiang Wang Senior Department of Ophthalmology the Third Medical Center of PLA General HospitalBeijingChina

AIM:To evaluate the accuracy of segmented measurement of axial length(AL)in high myopia filled with silicone oil by immersion B-scan ultrasonography(immersion B-scan).METHODS:From June 2016 to June 2020,a total of 67 ultra-high myopia inpatients(67 eyes)who underwent silicone oil removal combined with cataract extraction and intraocular lens(IOL)implantation were retrospectively *** preoperative axial length(AL)of 31 patients with severe cataract were segmented measured using immersion B-scan(B-scan group)and another 36 patients with mild or moderate cataract were measured using IOLMaster 500(IOLMaster group).The post-operative ALs in two groups were both measured using IOLMaster *** IOL power was calculated with Haigis *** differences in ALs between pre-and post-surgery,as well as the postoperative refractive spherical equivalent,absolute refractive error,the prediction deviation of postoperative refraction and best corrected visual acuity(BCVA)were ***:The pre-and post-operative ALs were 30.46±1.63 mm(range 28.09-33.51 mm)and 30.42±1.70 mm(range 28.03-33.90 mm)in B-scan group(t=0.644,P=0.542)and 30.51±1.21 mm(range 28.03-33.90 mm)and 30.43±1.27 mm(range 28.54-33.50 mm)in IOLMaster group(t=1.843,P=0.074),*** months after surgery,BCVA were 0.45±0.13(range 0.3-0.9)and 0.44±0.20(range 0.2-1.0)in B-scan and IOLMaster group respectively(t=0.086,P=0.932).There was no significant difference of the postoperative spherical equivalent(-3.11±0.65 D vs-3.21±0.51 D,t=0.671,P=0.505)and the absolute refractive error(0.589±0.340 vs 0.470±0.245 D,t=1.615,P=0.112)between two *** B-scan group,absolute refractive error within±0.50 D was found in 18 eyes(58.1%),within±1.00 D in 26 eyes(83.9%),and within±1.50 D in 31 eyes(100%).In IOLMaster group,absolute refractive error within±0.50 D was found in 23 eyes(63.9%),within±1.00 D in 34 eyes(94.4%),and within±1.50 D in 36 eyes(Z=0.757,P=0.449).CONCLUSION:The segmented measurement of ALs

关键词： high myopia axial length immersion B-ultrasound IOLMaster silicone oil cataract

Optimal Cooperative Secondary Control for Islanded DC Microgrids via a Fully Actuated Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 405-417页

作者： yi Yu Guo-Ping Liu yi huang Peng Shi IEEE Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and TechnologyShenzhen 518055China School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China School of Electrical and Mechanical Engineering the University of AdelaideSA 5005Australia Research and Innovation Centre Obuda University1034 BudapestHungary

DC-DC converter-based multi-bus DC microgrids(MGs) in series have received much attention, where the conflict between voltage recovery and current balancing has been a hot topic. The lack of models that accurately portray the electrical characteristics of actual MGs while is controller design-friendly has kept the issue active. To this end, this paper establishes a large-signal model containing the comprehensive dynamical behavior of the DC MGs based on the theory of high-order fully actuated systems, and proposes distributed optimal control based on this. The proposed secondary control method can achieve the two goals of voltage recovery and current sharing for multi-bus DC MGs. Additionally, the simple structure of the proposed approach is similar to one based on droop control, which allows this control technique to be easily implemented in a variety of modern microgrids with different configurations. In contrast to existing studies, the process of controller design in this paper is closely tied to the actual dynamics of the MGs. It is a prominent feature that enables engineers to customize the performance metrics of the system. In addition, the analysis of the stability of the closed-loop DC microgrid system, as well as the optimality and consensus of current sharing are given. Finally, a scaled-down solar and battery-based microgrid prototype with maximum power point tracking controller is developed in the laboratory to experimentally test the efficacy of the proposed control method.

关键词： DC microgrids distributed control high-order fully actuated system approach linear quadratic regulator microgrid modeling secondary control

Nb_(2)O_(5) nanocrystals decorated graphene composites as anode materials for high-performance dual-ion batteries

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Nano Research 2024年第3期17卷 1535-1541页

作者： Lei Wang fei huang Guoyin Zhu Zhihui Dai Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of Biofunctional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Institute of Advanced Materials and Flexible Electronics(IAMFE) School of Chemistry and Materials ScienceNanjing University of Information Science&TechnologyNanjing 210044China School of Chemistry and Molecular Engineering Nanjing Tech UniversityNanjing 211816China

Niobium oxide(Nb_(2)O_(5))is a promising material in photocatalytic,solar cell,electronic like electron field emitters,and especially lithium-ion batteries(LIBs)because of its adjustable morphologies,controllable crystal type,stable structure,and environmental ***,its low electrical conductivity lowers the rate performance and limits the practical applications in ***,we present a one-step solid-state synthesis of orthogonal Nb_(2)O_(5) nanocrystals/graphene composites(Nb_(2)O_(5)/G)as high-performance anode materials in *** from the nanoscale crystalline structure Nb_(2)O_(5) and highly-conductive graphene substrate,the as-prepared Nb_(2)O_(5)/G exhibits excellent electrochemical ***,a reversible structural phase transition between orthogonal Nb_(2)O_(5) and tetragonal Li1-xNbO_(2)(0

关键词： niobium oxide graphene anode dual-ion batteries graphite intercalation

Effect of the yaw angle on turbulent flow structures around the submarine model

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Journal of Hydrodynamics 2024年第3期36卷 421-434页

作者： yi-jing Hu yi Qu Qin Wu Biao huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China Beijing Institute of Electronic System Engineering Beijing100854China

The objective of this paper is to investigate the turbulent flow structures around the submarine model and evaluate the effect of the yaw angle on the turbulent flow *** large eddy simulation based on the boundary data immersion method is used to *** computational domain consists of 1.2×10^(8)uniformly distributed Cartesian orthogonal grid nodes to capture the basic flow characteristics around the *** pressure coefficient,friction coefficient and wake velocity distribution are in good agreement with the experimental *** different types of vortex structures were mainly captured around the model,including horseshoe vortex,sail tip vortex and crossflow separation *** the increase of the yaw angle,the asymmetry of the horseshoe vortex and the tip vortex gradually increases,and the vortex strength of the vortex leg on the windward of the horseshoe vortex and the vortex strength of the tip vortex also increase *** the crossflow separation vortex,the flow separation zone gradually expands and migrates downstream with the increase of the yaw angle.

关键词： Vortex structure submarine model boundary data immersion method yaw angle

Exploring the mechanisms of calcium carbonate deposition on various substrates with implications for effective anti-scaling material selection

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Petroleum Science 2024年第4期21卷 2870-2880页

作者： Lu Gong fei-yi Wu Ming-fei Pan Jun huang Hao Zhang Jing-Li Luo Hong-Bo Zeng College of Science China University of Petroleum Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum Basic Research Center for Energy Interdisciplinary College of Science China University of Petroleum Department of Chemical and Materials Engineering University of Alberta Key Laboratory of High Efficiency and Clean Mechanical Manufacture (Ministry of Education) School of Mechanical Engineering Shandong University

The unexpected scaling phenomena have resulted in significant damages to the oil and gas industries,leading to issues such as heat exchanger failures and pipeline clogging. It is of practical and fundamental importance to understand the scaling mechanisms and develop efficient anti-scaling strategies. However,the underlying surface interaction mechanisms of scalants(e.g., calcite) with various substrates are still not fully understood. In this work, the colloidal probe atomic force microscopy(AFM) technique has been applied to directly quantify the surface forces between calcite particles and different metallic substrates,including carbon steel(CR1018), low alloy steel(4140), stainless steel(SS304) and tungsten carbide,under different water chemistries(i.e., salinity and p H). Measured force profiles revealed that the attractive van der Waals(VDW) interaction contributed to the attachment of the calcium carbonate particles on substrate surfaces, while the repulsive electric double layer(EDL) interactions could inhibit the attachment behaviors. High salinity and acidic p H conditions of aqueous solutions could weaken the EDL repulsion and promote the attachment behavior. The adhesion of calcite particles with CR1018 and4140 substrates was much stronger than that with SS304 and tungsten carbide substrates. The bulk scaling tests in aqueous solutions from an industrial oil production process showed that much more severe scaling behaviors of calcite was detected on CR1018 and 4140 than those on SS304 and tungsten carbide, which agreed with surface force measurement results. Besides, high salinity and acidic p H can significantly enhance the scaling phenomena. This work provides fundamental insights into the scaling mechanisms of calcite at the nanoscale with practical implications for the selection of suitable antiscaling materials in petroleum industries.

关键词： Scaling phenomenon Metallic substrates Surface forces Bulk scaling tests

Acoustic characterization of hydrate formation and decomposition in clay-bearing sediments

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Petroleum Science 2024年第4期21卷 2830-2838页

作者： yi-Jian Zhu Xiao-Mei Yang Xing huang Hao Li Xiao-Hui Wang yi-fei Sun Peng Xiao Chang-Yu Sun Guang-Jin Chen State Key Laboratory of Heavy Oil Processing College of Chemical Engineering and Environment China University of Petroleum

Understanding the acoustic characteristics of hydrates in various sediments is crucial for hydrate resource detection and safe and efficient exploitation, as hydrate occurrence patterns vary greatly in different sediments. In this work, sediments with different bentonite contents, water saturations, and types were prepared to investigate the characteristics of P-wave velocity(reflecting the magnitude of hydrate saturation in the sediment) and amplitude(reflecting the degree of hydrate-sediment cementation) during hydrate formation and depressurization. During hydrate formation, the P-wave velocity and amplitude have similar trends. As clay content increases, the P-wave velocity increase rates quickened. On the other hand, the increased rate of P-wave velocity slows down with the increase of water saturation in the clay-bearing sediments. Comparing various types of sediment shows that the water absorption and swelling of bentonite reduce the pore space, speeding up the cementation of the hydrate with the sediment and increasing P-wave velocity at a faster rate. Correspondence between P-wave velocity and hydrate saturation is strongly related to sediment type, clay content, and water *** rapidly decreasing amplitude in the early stage of hydrate depressurization indicates that hydrate in clay-bearing sediments is weakly cemented to the sediments, which is prone to stratigraphic *** findings of this study offer guidance for hydrate resource assessments in clay-bearing sediments as well as geologic risk estimations during hydrate mining.

关键词： gas hydrate bentonite illite P-wave velocity amplitude

Modulating the electrode–electrolyte interface enables switchable selectivity in electrocatalytic furfural reduction

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Science China Chemistry 2024年第10期67卷 3193-3194页

作者： Jingfang Zhang yi huang Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education School of Chemical Engineering & PharmacyWuhan Institute of Technology College of Chemistry Central China Normal University

Furfural(FF), an important bio-based platform molecule, can be valorized to high-value-added chemicals(e.g., furfuryl alcohol(FA) or 2-methylfuran(MF)) through catalytic hydrogenation [1]. The traditional thermocatalytic transformation of FF always requires high-temperature and highpressure conditions [2]. Accordingly, electrocatalytic hydrogenation is emerging as a promising approach for the selective reduction of FF to FA or MF under environmentally friendly and benign conditions.

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Electric and thermal transport properties of topological insulator candidate LiMgBi

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Chinese Physics B 2021年第12期30卷 544-549页

作者： Hao OuYang Qing-Xin Dong yi-fei huang Jun-Sen Xiang Li-Bo Zhang Chen-Sheng Li Pei-Jie Sun Zhi-An Ren Gen-Fu Chen Institute of Physics and Beijing National Laboratory for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

We report the transport properties of a topological insulator candidate,*** electric resistivity of the title compound exhibits a metal-to-semiconductor-like transition at around 160 K and tends to saturation below 50 *** low temperatures,the magnetoresistance is up to~260%at 9 T and a clear weak antilocalization effect is observed in the low magnetic-field *** Hall measurement reveals that LiMgBi is a multiband system,where hole-type carriers(nh~1018 cm^(-3))play a major role in the transport ***,LiMgBi possess a large Seebeck coefficient(~440μV/K)and a moderate thermal conductivity at room temperature,which indicate that LiMgBi is a promising candidate in thermoelectric applications.

关键词： thermoelectric topological insulator crystal growth