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Journal of Rare Earths 2023年第12期41卷 2018-2024,I0007页

作者： Nanxi Lin Fangliang sheng Xin Chen Xiaolin hu Naifeng Zhuang College of Chemistry Fuzhou UniversityFuzhou350108China Key Laboratory of Non-destructive Testing Technology Fujian Polytechnic Normal UniversityFuqing350300China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108China

The magneto-optical effects of rare earth ferrite can be greatly improved by doping Ce^(3+)***_(3)with high Ce^(3+)concentration has excellent magneto-optical properties in *** due to its perovskite structure it is more suitable to be deposited on the substrates of optical devices compared with the commercial garnet *** this paper,the pure phase Ce_(x)Fe_(2-x)O_(3)films were successfully obtained on the quartz glass and -oriented SrTiO3crystal substrates by radio frequency magnetron *** effects of substrate and Ce:Fe ratio on the epitaxial orientation,magnetism and magnetooptical performance of films were systematically *** the Ce1.0Fe1.0O3/STO film,its MCD ellipticity(ψF) intensity can reach up to 4750(°)/cm in the visible band and 14090(°)/cm in near ultraviolet *** it also shows a strong vertical magnetic anisotropy,which makes it maintain a good thermal stability when the device size is *** mean that the Ce_(1.0)Fe_(1.0)O_(3)/STO film has a promising application in integrated optical communication devices.

关键词： Magneto-optical effect Thin film Magnetic anisotropy Magnetic circular dichroism Cerium Rare earths

Optimized Protection Strategies for HVDC Grid with Fault-blocking Modular Multilevel Converters for Overhead Line Applications

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Journal of Modern Power Systems and Clean Energy 2020年第6期8卷 1168-1177页

作者： sheng Yan Zhiyuan He Jie Yang Ming Kong Minqiang hu Southeast University NanjingChina Global Energy Interconnection Research Institute BeijingChina

The high-voltage direct current(HVDC)grid has been recognized as an effective solution for renewable energy ***,two main development trends for HVDC grids are being studied:a DC breaker based HVDC grid and fault-blocking converter based HVDC *** the former has a perfect performance for fault clearance,its development is still highly constrained by the cost and maturity of DC *** latter can extinguish DC faults by the fault-blocking *** using DC breakers,there is no bottleneck in its technical ***,in fault scenarios,such types of HVDC grids will be blocked at length for air-deionization,which is its main *** aim of this paper is to minimize its power interruption time,by optimizing protection coordination *** cover the most complex cases,the overhead line applications,in which the reclosure actions are required to be implemented,are *** this paper,the protection requirements of HVDC grids are first discussed,then the benefits of fault-blocking modular multilevel converters(MMCs)and their fault features are *** on this,a control function is designed to reduce the air-deionization *** minimize the influence of the DC faults,a separation methodology for restarting the system is *** effectiveness of the proposed protection coordination schemes is validated by PSCAD/EMTDC simulations.

关键词： Modular multilevel converter(MMC) high-voltage direct current(HVDC) overhead line fault-blocking converter protection coordination

Electrochemical determination of sulphide at multi-walled carbon nanotubes-dihexadecyl hydrogen phosphate composite film modified electrodes based on in situ synthesis of methylene blue

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Chinese Chemical Letters 2008年第1期19卷 73-75页

作者： An Min Xiang Li Zhou Cheng Guo hu sheng Shui hu College of Chemistry ＆ Molecular Sciences Wuhan University Wuhan 430072 China State Key Laboratory of Transducer Technology Chinese Academy of Sciences Beijing 100080 China

A novel electrochemical method for the determination of sulphide at a multi-walled carbon nanotube-dihexadecyl hydrogen phosphate composite film coated glassy carbon electrode （MWNTs-DHP/GCE） based on in situ synthesis of methylene blue （MB） was established. 2007 sheng Shui hu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Sulphide determination Electrochemical method Carbon nanotubes Methylene blue

Temporal continuity of visual attention for future gaze prediction in immersive virtual reality

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Virtual Reality & Intelligent Hardware 2020年第2期2卷 142-152页

作者： Zhiming hu sheng LI Meng GAI department of Computer Science and Technology School of Electronic Engineering and Computer SciencePeking UniversityBeijing 100871China Beijing Engineering Technology Research Center of Virtual Simulation and Visualization Peking UniversityBeijing 100871China

Background Eye tracking te chnology is receiving increased attention in the field of virtual ***,future gaze prediction is crucial in pre-computation for many applications such as gaze-contingent rendering,advertisement placement,and content-based *** explore future gaze prediction,it is necessary to analyze the temporal continuity of visual attention in immersive virtual *** In this paper,the concept of temporal continuity of visual attention is ***,an autocorrelation function method is proposed to evaluate the temporal ***,the temporal continuity is analyzed in both free-viewing and task-oriented *** Specifically,in free-viewing conditions,the analysis of a free-viewing gaze dataset indicates that the temporal continuity performs well only within a short time interval.A task-oriented game scene condition was created and conducted to collect users'gaze *** analysis of the collected gaze data finds the temporal continuity has a similar performance with that of the free-viewing *** continuity can be applied to future gaze prediction and if it is good,users'current gaze positions can be directly utilized to predict their gaze positions in the *** The current gaze's future prediction performances are further evaluated in both free-viewing and task-oriented conditions and discover that the current gaze can be efficiently applied to the task of short-term future gaze *** task of long-term gaze prediction still remains to be explored.

关键词： Temporal continuity Visual attention Autocorrelation analysis Gaze prediction Virtual reality

Magnitude-frequency relationship of debris flows in the Jiangjia Gully, China

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Journal of Mountain Science 2019年第6期16卷 1289-1299页

作者： GAO Yan-chao CHEN Ning-sheng hu Gui-sheng deNG Ming-feng Key Laboratory of Mountain Hazards and Land Surface Process Institute of Mountain Hazards and EnvironmentCASChengdu 610041China Chengdu Center China Geological SurveyChengdu 610081China University of Chinese Academy of Sciences Beijing 100049China

The magnitude-frequency(MF) relationship of debris flows is the basis for engineering designs and risk quantification. However, because of the lack of debris flow monitoring data, research progress in this area has been relatively slow. The MF relationship of debris flows in Jiangjia Gully, Yunnan Province was evaluated based on a regression analysis of 178 debris flow events that occurred from 1987-2004. The magnitude-cumulative frequency(MCF) relationship of the debris flows in the Jiangjia Gully is consistent with the linear logarithmic transformation function. Moreover, observed data for debris flows in hunshui Gully of Yunnan Province and huoshao Gully, Liuwan Gully, and Niwan Gully of Gansu Province were used to verify the function. The results showed that the MCF relationship of highfrequency debris flows is consistent with the power law equation, although the regression coefficients in the equation are considerably different. Further analysis showed a strong correlation between the differences in the constants and the drainage area and daily maximum precipitation.

关键词： debris flow Magnitude Cumulative frequency Drainage area Precipitation Jiangjia Gully

Effect of clay content to the strength of gravel soil in the source region of debris flow

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Journal of Mountain Science 2018年第10期15卷 2320-2334页

作者： CHEN Ning-sheng GAO Yan-chao Yang Cheng-lin hu Gui-sheng Key Laboratory of Mountain Hazards and Land Surface Process Institute of Mountain Hazards and EnvironmentCASChengdu 60041China Chengdu Center China Geological SurveyChengdu 610081China University of Chinese Academy of Sciences Beijing 100049China

The production of runoff in the source area of a debris flow is the consequence of a reduction in soil strength. Gravel soil is widely distributed in the source region, and the influence of its clay content on soil strength is one of the important questions regarding the formation mechanism of debris flows. In this paper, the clay content in gravel soil is divided into groups of low clay content(1%, 2, 5%), moderate clay content(3.75%, 5.00%, 6.25%, 7.5%) and high clay content(10.0%, 12.5%, 15%). Tests of the unconsolidated undrained shear strength and consolidated drained shear strength were performed. The unconsolidated undrained shearing(UU) experiment simulates the rapid shear failure of loose gravel soil under the conditions of brief heavy rainfall. The consolidated drained shearing(CD) experiment simulates creep failure of consolidated sediment during extended rainfall. The pore water pressure first increased and then decreased as the clay content increased, and the increase in pore pressure was relatively high in the gravel soil sample when the clay content is in the range of 3.25-7.50%, and stress in the gravel soil is relatively low for a moderate clay content. Gravelly soils with a moderate clay content are moreprone to debris-flow initiation. This paper presents a mathematical formula for the maximum shear stress and clay content of gravel soil under two conditions. The key processes whereby the soil fails and triggers a debris flow—volume contraction of soil, expansion of clay soil, and rise of pore pressure―cause reductions in the soil friction force and enhancement of the water content in the clay particles, and subsurface erosion of soil reduces the soil viscosity, which eventually reduces the soil strength so that the soil loses its stability, liquefies and generates a debris flow.

关键词： debris flows Gravel soil Clay content Maximum shear stress Pore water pressure

Gel fire suppressants for controlling underground heating

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Journal of Coal Science & Engineering(China) 2011年第3期17卷 256-264页

作者： hu sheng-gen XUE sheng Energy Technology Commonwealth Scientific and Industrial Research Organisation Newcastle NSW 2300 Australia Exploration and Mining Commonwealth Scientific and Industrial Research Organisation Kenmore QLD 4069 Australia

One of the major safety issues in coal mining is heatings and the resultant spontaneous combustion in underground coal mines. CSIRO researchers have developed a number of polymer gels suitable for controlling beatings in coal mines. These gels were developed to meet strict selection criteria including easy preparation, no or low toxicity, controllable gelation time, adaptable to mine water chemistry, adjustable viscosity, relatively long gel life, thermally and chemically stable and low cost. The HPAM-Aluminum Citrate gel system was identified to be the most favourable gel system for fire suppression in under- ground coal mines. These gels can be applied to the areas undergoing coal heating or gas leakage at a controllable gelation time and impermeable gel barriers can be formed in the areas to block ingress of air.

关键词： underground heating gel barrier gel preparation gelation time

Neural Network State Learning Based Adaptive Terminal ILC for Tracking Iteration-varying Target Points

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International Journal of Automation and computing 2015年第3期12卷 266-272页

作者： Yu Liu Rong-hu Chi Zhong-sheng Hou School of Automation and Electronic Engineering Qingdao University of Science and Technology Advanced Control Systems Lab School of Electronics and Information Engineering Beijing Jiaotong University

Terminal iterative learning control(TILC) is developed to reduce the error between system output and a fixed desired point at the terminal end of operation interval over iterations under strictly identical initial conditions. In this work, the initial states are not required to be identical further but can be varying from iteration to iteration. In addition, the desired terminal point is not fixed any more but is allowed to change run-to-run. Consequently, a new adaptive TILC is proposed with a neural network initial state learning mechanism to achieve the learning objective over iterations. The neural network is used to approximate the effect of iteration-varying initial states on the terminal output and the neural network weights are identified iteratively along the iteration axis.A dead-zone scheme is developed such that both learning and adaptation are performed only if the terminal tracking error is outside a designated error bound. It is shown that the proposed approach is able to track run-varying terminal desired points fast with a specified tracking accuracy beyond the initial state variance.

关键词： Adaptive terminal iterative learning control neural network initial state learning iteration-varying terminal desired points ini

High‑Performance Fasciated Yarn Artificial Muscles Prepared by Hierarchical Structuring and Sheath-Core Coupling for Versatile Textile Actuators

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Advanced Fiber Materials 2023年第4期5卷 1534-1547页

作者： Nan sheng Yangyang Peng Fengxin Sun Jinlian hu MOE Key Laboratory of Eco‑Textiles Jiangnan UniversityWuxi 214122China department of Biomedical Engineering City University of Hong KongHong Kong S.A.R 999077China

High-performance yarn artificial muscles are highly desirable as miniature actuators,sensors,energy harvesters,and soft ***,achieving a yarn artificial muscle that covers all the properties of excellent actuation performance,mechanical robustness,structural stability,and high scalability by a low-cost strategy is still a great ***,a bio-inspired fasciated yarn structure is first reported for creating robust high-performance yarn artificial *** conventional strategies that leverage costly materials or complex processing,the developed yarn artificial muscles are constructed by hierarchically helical and sheath-core assembly design of cost-effective common fibers,such as viscose and *** hierarchically helical sheath structure pushes the theoretical limit of the inserted twist in yarns and endows the yarn muscles with large stroke(5815°cm^(-1))and high work capacity(23.5 J kg^(-1)).Due to the rapid water transfer and efficient energy conversion of inter-sheath-core coupling,the as-prepared yarn muscles possess fast response,high rotation accelerated speed,and low recovery ***,the inactive core yarn serves as support for internal tethering and load-bearing,enabling these yarn muscles to maintain a self-stable structure,robust life cycle and *** show that the yarn muscle fabricated in this method is readily available and highly scalable for achieving high-dimensional actuation deformations,which considerably broadens the application scenarios of artificial muscles.

关键词： Artificial muscles Hierarchical structuring Actuators Smart textiles

Instability from Steady and Axisymmetric to Steady and Asymmetric Floating Half Zone Convection in a Fat Liquid Bridge of Larger Prandtl Number

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Chinese Physics Letters 1999年第11期16卷 822-823页

作者： CHEN Qi-sheng hu Wen-rui Institute of Mechanics Chinese Academy of SciencesBeijing 100080 department of Mechanical Engineeing State University of New YorkStony BrookNY 11794USA

The linear instability analysis of the present paper shows that the thermocapillary convection in a half floating zone of larger Prandtl number has a steady instability mode ωi = 0 and m = 1 for a fat liquid bridge V = 1.2 with small geometrical aspect ratio A = 0.6. This conclusion is different from the usual idea of hydrothermal instability, and implies that the instability of the system may excite a steady and axial asymmetric state before the onset of oscillation in the case of large Prandtl number.

关键词： implies floating conclusion