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Lithium cobaltate:a novel host material enables high-rate and stable lithium-sulfur batteries

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Rare Metals 2018年第11期37卷 929-935页

作者： Wen Ma Qing xu GRINM Bohan (Beijing) Publisher Co. Ltd.GRINM Group Co.Ltd. Subinstitute of Standardization Theory and Strategy China National Institute of Standardization

Element sulfur is highly attractive due to their potentially low cost and environmental ***, polysulfides dissolution hinders the lithiumsulfur(Li-S) batteries toward commercialization. To overcome these issues, in this work, lithium cobaltate as a commercial material, for the first time, was devoted to engineering the electrode structure and composition to improve the performance. When incorporated with 80% sulfur powder, the synergetic effects of cobalt atoms and interlayer spaces effectively enable the production of Li-S batteries with a relatively high discharge capacity of 1420 mAh·g-1at the low surface current density of 1 mA·cm-2and stable capacity retention of 650 mAh·g-1at high surface current density of 6 mA·cm-2. The introduction of lithium cobaltate is a viable approach for successfully developing practical Li-S batteries.

关键词： Lithium cobaltate Polysulfides dissolution Electrochemical properties Lithium-sulfur batteries

Intuitionistic fuzzy C-means clustering algorithms

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Journal of Systems Engineering and Electronics 2010年第4期21卷 580-590页

作者： Zeshui xu Junjie Wu School of Economics and Management Southeast UniversityNanjing 210096P.R.China Institute of Sciences PLA University of Sciences and TechnologyNanjing 210007P.R.China Department of Information Systems School of Economics and ManagementBeihang UniversityBeijing 100191P.R.China

Intuitionistic fuzzy sets(IFSs) are useful means to describe and deal with vague and uncertain *** intuitionistic fuzzy C-means algorithm to cluster IFSs is *** each stage of the intuitionistic fuzzy C-means method the seeds are modified,and for each IFS a membership degree to each of the clusters is *** the end of the algorithm,all the given IFSs are clustered according to the estimated membership ***,the algorithm is extended for clustering interval-valued intuitionistic fuzzy sets(IVIFSs).Finally,the developed algorithms are illustrated through conducting experiments on both the real-world and simulated data sets.

关键词： intuitionistic fuzzy set(IFS) intuitionistic fuzzy Cmeans algorithm clustering interval-valued intuitionistic fuzzy set(IVIFS).

Entanglement and Teleportation of Pair Cat States in Amplitude Decoherence Channel

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Communications in Theoretical Physics 2009年第7期52卷 45-49页

作者： xu Hang-Shi xu Jing-Bo Zhejiang Institute of Modern Physics and Physics Department Zhejiang University Hangzhou 310027 China

The dynamic behavior of the entanglement for the pair cat states in the amplitude decoherence channel isstudied by adopting the entanglement of formation determined by the ***,we consider the teleportationby using joint measurements of the photon-number sum and phase difference with the pair cat states as an entangleresource and discuss the influence of amplitude decoherence on the mean fidelity of the teleportation.

关键词： entanglement teleportation pair cat states

Acupuncture:a new method to treat tic disorders in children

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Traditional Medicine Research 2022年第2期7卷 53-58页

作者： Jun-Ze Geng Jing-Yu xu Xiao-Ge Wang Yan-Qi Liu Yang-Ning Cui xin-Min Li First Teaching Hospital of Tianjin University of Traditional Chinese Medicine Tianjin 300000China. National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300000China.

Tic disorder is a common pediatric neurological disorder that severely affects children’s quality of *** in fact,there is still a lack of a very effective treatment for tic *** as a flexible treatment time,treatment cycle control,easy to operate treatment method,widely used in the field of neurological disorder,widely praised by clinicians and *** the same time,tic disorder belongs to the category of chronic inflammatory convulsion in traditional Chinese medicine,and acupuncture has a good effect of relieving spasticity and fewer adverse reactions,which makes acupuncture have a good application ***,more and more studies about acupuncture treatment of tic disorder in children have been *** main methods of treating tic disorder are acupuncture,electroacupuncture,scalp acupuncture and ear *** efficacy of acupuncture alone or in combination with other drugs such as tiapride hydrochloride and haloperidol has been shown to be *** safety of acupuncture is also commendable,and clinical trials showing that the combination of acupuncture and medication can reduce the incidence and severity of adverse drug *** to the existing studies,acupuncture can promote the development and repair of the nervous system,regulate the secretion of neurotransmitters,and reduce the occurrence of local discomfort,which may be the main mechanism of acupuncture treatment of tic disorders.

关键词： tic disorder pediatrics mechanism research alternative therapy research progress

Experimental studies on active control of a dynamic system via a time-delayed absorber

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Acta Mechanica Sinica 2015年第2期31卷 229-247页

作者： Jian xu Yixia Sun School of Aerospace Engineering and Applied Mechanics Tongji University

The traditional passive absorber is fully effective within a narrow and certain frequency *** solve this problem,a time-delayed acceleration feedback is introduced to convert a passive absorber into an active *** the inherent and the intentional time delays are *** former mainly comes from signal acquiring and processing,computing,and applying the actuation force,and its value is *** latter is introduced in the controller,and its value is actively ***,the mechanical model is established and the frequency response equations are *** regions of stability are delineated in the plane of control ***,the design scheme of control parameters is performed to help select the values of the feedback gain and time ***,the experimental studies are *** of both negative and positive feedback control are *** results show that the proper choices of control parameters may broaden the effective frequency band of vibration ***,the time-delayed absorber greatly suppresses the resonant response of the primary system when the passive absorber totally *** experimental results are in good agreement with the theoretical predictions and numerical simulations.

关键词： Vibration absorber Time-delayed feedback Vibration control Stability

Hydrologic Response to Future Climate Change in the Dulong-Irra-waddy River Basin Based on Coupled Model Intercomparison Project 6

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Chinese Geographical Science 2024年第2期34卷 294-310页

作者： xu Ziyue MA Kai YUAN xu HE Daming Institute of International Rivers and Eco-security Yunnan UniversityKunming 650500China Yunnan Key Laboratory of International Rivers and Transboundary Eco-security Kunming 650500China

Within the context of the Belt and Road Initiative(BRI)and the China-Myanmar Economic Corridor(CMEC),the Dulong-Ir-rawaddy(Ayeyarwady)River,an international river among China,India and Myanmar,plays a significant role as both a valuable hydro-power resource and an essential ecological ***,the water resources and security exhibit a high degree of vulnerabil-ity to climate change *** research evaluates climate impacts on the hydrology of the Dulong-Irrawaddy River Basin(DIRB)by using a physical-based hydrologic *** crafted future climate scenarios using the three latest global climate models(GCMs)from Coupled Model Intercomparison Project 6(CMIP6)under two shared socioeconomic pathways(SSP2-4.5 and SSP5-8.5)for the near(2025-2049),mid(2050-2074),and far future(2075-2099).The regional model using MIKE SHE based on historical hydrologic processes was developed to further project future streamflow,demonstrating reliable performance in streamflow simulations with a val-idation Nash-Sutcliffe Efficiency(NSE)of *** showed that climate change projections showed increases in the annual precip-itation and potential evapotranspiration(PET),with precipitation increasing by 11.3%and 26.1%,and PET increasing by 3.2%and 4.9%,respectively,by the end of the century under SSP2-4.5 and *** changes are projected to result in increased annual streamflow at all stations,notably at the basin’s outlet(Pyay station)compared to the baseline period(with an increase of 16.1%and 37.0%at the end of the 21st century under SSP2-4.5 and SSP5-8.5,respectively).Seasonal analysis for Pyay station forecasts an in-crease in dry-season streamflow by 31.3%-48.9%and 22.5%-76.3%under SSP2-4.5 and SSP5-8.5,respectively,and an increase in wet-season streamflow by 5.8%-12.6%and 2.8%-33.3%,***,the magnitude and frequency of flood events are pre-dicted to escalate,potentially impacting hydropower production and food security *** res

关键词： climate change hydrologic response Coupled Model Intercomparison Project 6(CMIP6) MIKE SHE(Système Hydrologique Europeén) Dulong-Irrawaddy River Basin

Angle estimation in bistatic MIMO radar using improved reduced dimension Capon algorithm

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Journal of Systems Engineering and Electronics 2013年第1期24卷 84-89页

作者： Xiaofei Zhang Dazhuan xu Electronic Engineering Department Nanjing University of Aeronautics and Astronautics

This paper discusses the problem of direction of departure （DOD） and direction of arrival （DOA） estimation for a bistatic multiple input multiple output （MIMO） radar, and proposes an improved reduced-dimension Capon algorithm therein. Compared with the reduced-dimension Capon algorithm which requires pair matching between the two-dimensional angle estimation, the pro- posed algorithm can obtain automatically paired DOD and DOA estimation without debasing the performance of angle estimation in bistatic MIMO radar. Furthermore, the proposed algorithm has a lower complexity than the reduced-dimension Capon algorithm, and it is suitable for non-uniform linear arrays. The complexity of the proposed algorithm is analyzed and the Cramer-Rao bound （CRB） is also derived. Simulation results verify the usefulness of the proposed algorithm.

关键词： multiple input multiple output (MIMO) radar angle estimation Capon algorithm non-uniform array.

A non-uniform grid for triangular differential quadrature

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Science China(Physics,Mechanics & Astronomy) 2016年第12期59卷 52-59页

作者： HongZhi Zhong Jia xu Department of Civil Engineering Tsinghua University

The triangular differential quadrature method based on a non-uniform grid is proposed in the paper. Explicit expressions of the non-uniform grid point coordinates are given and the weighting coefficients of the triangular differential quadrature method are determined with the aid of area coordinates. Two typical examples are presented to testify the effectiveness of the non-uniform grid. It is shown that rapid convergence is achieved under the non-uniform grid in comparison with those from the uniform grid with the same order of approximation.

关键词： differential quadrature triangular differential quadrature non-uniform grid weighting coefficient affine transformation

Ultrawide-band radar imagery from multiple incoherent frequency subband measurements

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Journal of Systems Engineering and Electronics 2011年第3期22卷 398-404页

作者： Xiaojian xu Jia Li School of Electronic and Information Engineering Beihang UniversityBeijing 100191P.R.China Department of Electrical Computer and Systems EngineeringRensselaer Polytechnic InstituteTroy NY12180USA

The problem of combined radar imagery from multiple sparse frequency subbands initially incoherent to each other is of practical importance for radar target discrimination.A new coherent processing technique based on probability density analysis of the subband data is proposed,which is applicable for radar imaging from measurements of two or more initially incoherent radar *** coherence parameters for both amplitude and phase are obtained by combining modern spectral analysis with probability density *** major advantage of the proposed technique lies in that it enables much more robust cohering for the sparse subband data of real-world complex targets.

关键词： radar imagery coherent processing subband spectral analysis.