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cNN-LSTM based incremental attention mechanism enabled phase-space reconstruction for chaotic time series prediction

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Journal of Electronic Science and Technology 2024年第2期22卷 77-90页

作者： Xiao-Qian Lu Jun Tian qiang Liao Zheng-Wu Xu Lu Gan Bidding and Purchasing center University of Electronic Science and Technology of ChinaChengdu611731China Yibin Research Institute University of Electronic Science and Technology of ChinaYibin644000China Sc.ool of Information and communication Engineering University of Electronic Science and Technology of ChinaChengdu611731China

To improve the prediction accuracy of chaotic time series and reconstruct a more reasonable phase space structure of the prediction network,we propose a convolutional neural network-long short-term memory(cNN-LSTM)prediction model based on the incremental attention ***,a traversal search is conducted through the traversal layer for finite parameters in the phase ***,an incremental attention layer is utilized for parameter judgment based on the dimension weight criteria(DWc).The phase space parameters that best meet DWc are selected and fed into the input ***,the constructed cNN-LSTM network extracts spatio-temporal features and provides the final prediction *** model is verified using Logistic,Lorenz,and sunspot chaotic time series,and the performance is compared from the two dimensions of prediction accuracy and network phase space ***,the cNN-LSTM network based on incremental attention is compared with long short-term memory(LSTM),convolutional neural network(cNN),recurrent neural network(RNN),and support vec.or regression(SVR)for prediction *** experiment results indicate that the proposed composite network model possesses enhanced capability in extracting temporal features and achieves higher prediction ***,the algorithm to estimate the phase space parameter is compared with the traditional c.o,false nearest neighbor,and c-c,three typical methods for determining the chaotic phase space *** experiments reveal that the phase space parameter estimation algorithm based on the incremental attention mechanism is superior in prediction accuracy compared with the traditional phase space reconstruction method in five networks,including cNN-LSTM,LSTM,cNN,RNN,and SVR.

关键词： chaotic time series Incremental attention mechanism Phase-space reconstruction

c.ordination environments build up and tune a superior synergistic “genome” toward novel trifunctional (TM-N_(x)o_(4−x))@g- c_(16)N_(3)-H_(3): High-throughput inspection of ultra-high activity for water splitting and oxygen reduction reactions

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Nano Research 2024年第4期17卷 2337-2351页

作者： chunyao Fang Xian Wang qiang Zhang Xihang Zhang chenglong Shi Jingcheng Xu Mengyu Yang Department of Physics University of Shanghai for Science and TechnologyShanghai 200093China Sc.ool of Materials and chemistry University of Shanghai for Science and TechnologyShanghai 200093China

Emerging as a prominent area of focus in energy conversion and storage technologies,the development of highly active metal-based single-atom catalysts(SAcs)holds great signiﬁcance in searching alternatives to replace prec.ous metals toward the efficient,stable,and low-cost hydrogen evolution reaction(HER),as well as the oxygen evolution reaction(oER)and the oxygen reduction reaction(oRR).combining the tremendous tunability of ligand and c.ordination environment with rich metal-based electrocatalysts can create breakthrough opportunities for achieving both high stability and ***,we propose a novel and stable holey graphene-like carbon nitride monolayer g-c_(16)N5(N_(4)@g-c_(16)N_(3))stoichiometries interestingly behaving as a natural substrate for constructing SAcs((TM-N_(4))@g-c_(16)N_(3)),whose evenly distributed holes map rich and uniform nitrogen c.ordination positions with electron-rich lone pairs for anc.oring transition metal(TM)***,we employed density functional theory(DFT)calculations to systematically investigate the electrocatalytic activity of(TM-N_(4))@g-c_(16)N_(3) toward HER/oER/oRR,meanwhile considering the synergistic modulation of H-loading and o-c.ordination((TM-N_(x)o_(4-x))@g-c_(16)N_(3)^(-)H_(3),x=0–4).Together a“four-step procedure”screening mechanism with the first-principles high-throughput calculations,we find that(Rh-N_(4))and(Ir-N_(2)o_(2)-II)distributed on g-c_(16)N_(3)^(-)H_(3) can modulate the adsorption strength of the adsorbates,thus achieving the best HER/oER/oRR performance among 216 candidates,and the lowest overpotential of 0.098/0.3/0.46 V and 0.06/0.48/0.45 V,***,the d-band center,crystal orbital Hamilton population(coHP),and molecular orbitals are used to reveal the oER/oRR activity ***,the Rh/Ir-d orbital is dramatically hybridized with the o-p orbital of the oxygenated adsorbates,so that the lone-electrons incipiently locate at the antibonding orbital pair up and popula

关键词： single atom catalysts loading and c.ordination hydrogen evolution reaction oxygen evolution reaction oxygen reduction reaction

Irreducible Representations of GL_(n)(c.of Minimal Gelfand-Kirillov Dimension

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Acta Mathematica Sinica,English Series 2024年第3期40卷 639-657页

作者： Zhan qiang BAI Yang Yang cHEN Dong Wen LIU Bin Yong SUN Sc.ool of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China Sc.ool of Sciences JiangnanUniversityWui214122P.R.China Sc.ool of Mathematical Sciences Zhejiang UniversityHangzhou 310058P.R.China Institute for Advanced Study in Mathematics Zhejiang UniversityHangzhou 310058P.R.China

In this article,by studying the Bernstein degrees and Goldie rank polynomials,we es-tablish a comparison between the irreducible representations of G=GL_(n)(c)possessing the minimal Gelfand-Kirillov dimension and those induced from finite-dimensional representations of the maximal parabolic subgroup of G of type(n-1,1).We give the transition matrix between the two bases for the corresponding coherent families.

关键词： Bernstein degree coherent continuation Gelfand-Kirillov dimension

Pic.orial review of hepatic echinococ.osis:Ultrasound imaging and differential diagnosis

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World Journal of Gastroenterology 2024年第37期30卷 4115-4131页

作者： Yi Tao Yi-Fei Wang Jun Wang Shuang Long Barnabas c Seyler Xiao-Fei Zhong qiang Lu Department of Medical Ultrasound West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Radiology Gaoping District People’s HospitalNanchong 637100Sichuan ProvinceChina Shude International Chengdu Shude High SchoolChengdu 610066Sichuan ProvinceChina Department of Environment Sichuan UniversityChengdu 610065Sichuan ProvinceChina

Echinococ.osis is a zoonotic disease caused by parasites belonging to the genus Echinococcus that primarily affect the *** western plateau and pastoral areas of china are high-risk regions for hepatic cystic echinococ.osis and hepatic alveolar echinococ.osis(HAE).The high late mortality rate associated with HAE underscores the critical need for early diagnosis to improve cure rates and mitigate the disease burden in endemic ***,the World Health orga-nization recommends ultrasonography as the preferred initial screening method for hepatic ***,distinguishing between specific types of lesions,such as those of hepatic cystic echinococ.osis and HAE,and other focal liver lesions is *** address this issue,contrast-enhanced ultrasound is recommended as a tool to differentiate solid and cysto-solid hepatic echino-coc.osis from other focal liver lesions,significantly enhancing diagnostic *** this comprehensive review,we discuss the progression of hepatic echinococ.osis and detail the imaging features of various types of echinococ.osis using conventional,contrast-enhanced,and intraoperative ultrasound *** objective is to provide robust imaging evidence and guidance for early diagnosis,clinical decision making,and postoperative follow-up in regions with high disease prevalence.

关键词： Echinococ.osis Zoonotic disease Ultrasound contrast-enhanced ultrasound Diagnosis

Design and implementation of low-cost geomagnetic field monitoring equipment for high-density deployment

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Applied Geophysics 2024年第3期21卷 505-512,618页

作者： Sun Lu-qiang Bai Xian-fu Kang Jian Zeng Ning Zhu Hong Zhang Ming-Dong Tianjin Earthquake Agency Tianjin 300201China Yunnan Earthquake Agency Kunming 650224China

The observation of geomagnetic field variations is an important approach to studying earthquake *** 1987,the china Earthquake Administration has explored this seismomagnetic *** particular,they studied local magnetic field anomalies over the chinese mainland for earthquake *** to the years of research on the seismomagnetic relationship,earthquake prediction experts have concluded that the compressive magnetic effect,tec.onic magnetic effect,electric magnetic fluid effect,and other fac.ors contribute to preearthquake magnetic ***,this involves a small magnitude of magnetic field *** is difficult to relate them to the abnormal changes of the extremely large magnetic field in regions with extreme earthquakes owing to the high cost of professional geomagnetic equipment,thereby limiting large-scale ***,it is difficult to obtain strong magnetic field changes before an *** Tianjin Earthquake Agency has developed low-cost geomagnetic field observation equipment through the Beijing–Tianjin–Hebei geomagnetic equipment test *** new system was used to test the availability of equipment and determine the findings based on big data..

关键词： geomagnetic field earthquake prediction low cost high density big data

The homogenous growth of co-based c.ordination compound on graphene nanosheet for high-performance K-organic battery and its reaction mechanism

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Rare Metals 2024年第4期43卷 1622-1634页

作者： Qian-Qian Peng Yi-Ting Wang Shuo Qi Yao Xiao Yong Wang Shuang-qiang chen Sc.ool of Environmental and chemical Engineering Shanghai UniversityShanghai200444China Sc.ool of chemistry and Materials Engineering Wenzhou UniversityWenzhou325035China

Metal c.ordination compounds(Mccs)are gaining popularity for potassium-ion batteries(PIBs)owing to their tuneable structure,multiple reaction sites,low cost and unique ***,they are generally subjected to intrinsic features of the sluggish ionic diffusion coefficient,low electronic conductivity and slow ***,a new Mcc material of cobalt-1,3,5-trioxy-2,4,6-triamino-benzo(co-TB)c.ordination compound was synthesized and homogenously grown on the surface of graphene nanosheets(GNS),forming a co-TB@GNS composite with enhanced electronic conductivity and flexible *** from the overall enhanced conductivity,high surface area and abundant activated K-storage sites,co-TB@GNS electrodes have exhibited superior cycling performance with high reversible capacities(312 mAh·g^(-1)after 100 cycles at 100 mA·g^(-1),224 mAh·g^(-1)after 500 cycles at 1 A·g^(-1))and better rate performances compared with the pure co-TB compound when served as PIB's ***,multiple in-situ measurement techniques have jointly confirmed that the organic functional groups(c.o,c=N and c=c.of benzene rings)and co^(2+)in co-TB are the main reversible K-storage sites,including in-situ Fourier transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD),and partial capacity contribution is originated from GNS by the apparent K-storage behavior in the in-situ XRD pattern,proving the possibility of K-storage for metal-organic materials.

关键词： Metal c.ordination compounds Potassiumion battery cobalt c.ordination compound K-storage mechanism

Facile fabrication of graphene/g-c_(3)N_(4) for electromagnetic wave absorption

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Nano Research 2024年第3期17卷 1687-1698页

作者： qiang Su Yunfei He Dongdong Liu Daguang Li Long Xia Xiaoxiao Huang Bo Zhong Sc.ool of Materials Science and Engineering Harbin Institute of Technology WeihaiWeihai 264209China Weihai Yunshan Technology co. Ltd.Weihai 264200China State Key Laboratory on Integrated optoelectronics College of Electronic Science&EngineeringJilin UniversityChangchun 130012China Sc.ool of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

With the development of the miniaturization of electronic equipment and lightweight weapon equipment,there are new requirements for electromagnetic wave absorption material(EMWAM).EMWAM has outstanding electromagnetic wave absorption properties and lightweight characteristics become an important direction of *** this study,graphene/g-c_(3)N_(4)(GGcN)EMWAM was first synthesized in situ by simple heat treatment,in which the g-c_(3)N_(4) had a porous structure and dispersed on the surface of *** impedance matching of the GGcN was well adjusted by decreasing the dielectric constant and attenuation constant due to the g-c_(3)N_(4) semiconduc.or property and the graphite-like *** EMW loss mechanism of GGcN was also analyzed by simulating GGcN’s electric field mode distribution and resistance loss power *** analysis result shows that the distribution of g-c_(3)N_(4) among GGcN sheets can produce more polarization effects and relaxation effects by increasing the lamellar ***,the polarization loss of GGcN could be increased successfully by porous g-c_(3)N_(4).Ultimately,the EMW absorption property of GGcN is optimized significantly,and GGcN exhibits excellent EMW absorption *** the thickness is 2 mm,the effective absorption bandwidth(EAB)can reach 4.6 GHz,and when the thickness is 4.5 mm,the minimum reflection loss(RLmin)at 4.56 GHz can reach-34.69 ***,the practical application of EMWAM was studied by radar c.oss-section(RcS)simulation,showing that GGcN has a good application prospect.

关键词： graphene/g-c_(3)N_(4) impedance matching simulation analysis dielectric loss excellent electromagnetic wave absorption

Evolution of mic.ostructure and texture of AZ80 magnesium alloy under hot torsion with constant decreasing temperature rate

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Journal of Magnesium and Alloys 2024年第4期12卷 1619-1637页

作者： Yongbiao Yang Jinxuan Guo cuiying Wang Wenxuan Jiang Zhimin Zhang qiang Wang Xing Zhang college of Materials Science and Engineering North University of ChinaLane 3Xueyuan RoadTaiyuanShanxi 030051China North Hongyang mechanical and electronic limited company of Henan Province China

Hot torsion tests for AZ80 magnesium alloy were carried out in the temperature range of 380℃-260℃,with a constant decreasing temperature rate of 10℃/s in order to weaken the basal texture and refine the *** results indicated that the average grain sizes were refined forming gradient structure with increasing specimen radial position from center(12.2-5.4μm),and that the initial basal texture intensity of the extruded magnesium alloy was weakened from 46.2 to ***,the extension twins(ETs)could be disintegrated from the twins forming separated twins with smaller ***,ETs with the same twin variant intersecting with each other could be coalesced forming grains with similar orientation,while ETs with different twin variants were separated by twins boundaries contributing to grain ***,in addition to the conventional continuous dynamic recrystallized(cDRX)grains with 30˚orientation rotated around c-axis of the parent grains,cDRXed grains with 30˚rotation around a-axis and random rotation axis were also ***,the cDRX evolution induced twins were also elaborated,exhibiting the complex competition between cDRX and *** torsion deformation with constant decreasing temperatures rate is an effective way of grain refinement and texture modification.

关键词： Texture Mic.ostructure Hot torsion Decreasing temperature AZ80

Superatom-assembled boranes,carboranes,and low-dimensional boron nanomaterials based on aromatic icosahedral B_(12)and c_(2)B_(10)

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Nano Research 2024年第7期17卷 6734-6740页

作者： Qiao-Qiao Yan Yan-Fang Wei qiang chen Yue-Wen Mu Si-Dian Li Institute of Molecular Science Shanxi UniversityTaiyuan 030006China

Using the experimentally known aromatic icosahedral superatoms I_(h)B_(12)H_(12)2−and D_(5d)1,12-c_(2)B_(10)H_(12)as building blocks and based on extensive density functional theory calculations,we predict herein a series of core–shell superpolyhedral boranes and carboranes in a bottom-up approach,including the high-symmetry Th B_(12)@B_(152)H_(72)2−(2),c2h c_(2)B_(10)@B_(152)H_(72)(3),D_(3d)B_(12)@B_(144)H_(66)(4),I_(h)B_(12)@c_(24)B_(12)0H_(72)2−(6),and D_(5d)c_(2)B_(10)@c_(24)B_(12)0H_(72)(7).More interestingly,the superatom-assembled linear D2h B_(36)H_(32)^(2−)(8),c.ose-packed planar D_(3d)B_(84)H_(60)^(2−)(10),and nearly c.ose-packed core−shell D_(3d)B_(12)@B144H_(6)6(4)can be extended periodically to form the one-dimensional(1D)α-rhombohedral borane nanowire B_(12)H_(10)(Pmmm)(9),two-dimensional(2D)α-rhombohedral monolayer borophane B_(12)H_(6)(P m1)(11),and the experimentally known three-dimensional(3D)α-rhombohedral boron(R m)(12)which can be viewed as an assembly of the monolayer B_(12)H_(6)(11)staggered in vertical direction,setting up a bottom-up strategy to form low-dimensional boron-based nanomaterials from their borane“seeds”via partial or complete *** bonding analyses indicate that the high stability of these nanostructures originates from the spherical aromaticity of their icosahedral B_(12)or c_(2)B_(10)structural units which possess the universal skeleton electronic configuration of 1S21P61D101F8 following the Wade’s n+1 *** infrared(IR)and Raman spectra of the most-concerned neutral B_(12)@B144H_(6)6(4)and c_(2)B_(10)@c_(24)B_(12)0H_(72)(7)are computationally simulated to facilitate their experimental characterizations.

关键词： superatom-assembling bottom-up approach density functional theory superpolyhedral boranes superpolyhedral carboranes borophanes