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On m-ovoids of finite classical polar spaces with an irreducible transitive automorphism group

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Science China mathematics 2024年第3期67卷 683-712页

作者： Tao Feng Weicong Li ran Tao School of mathematical Sciences Zhejiang UniversityHangzhou 310027China Department of mathematics and National Center for Applied mathematics Shenzhen Southern University of Science and TechnologyShenzhen 518055China Key Laboratory of Cryptologic Technology and Information Security Ministry of EducationShandong UniversityQingdao 266237China School of Cyber Science and Technology Shandong UniversityQingdao 266237China

In this paper, we classify the m-ovoids of finite classical polar spaces that admit a transitive automorphism group acting irreducibly on the ambient vector space. In particular, we obtain several new infinite familie... 详细信息

关键词： transitive m-ovoids irreducible action finite classical polar spaces primitive divisor

Evaluation of Nonbreaking Wave-Induced mixing Parameterization Schemes Based on a One-Dimensional Ocean model

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Journal of Ocean University of China 2024年第3期23卷 567-576页

作者： TAng ran HUAng Chuanjiang DAI Dejun WAng Gang The First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical modeling Laoshan LaboratoryQingdao 266237China Shandong Key Laboratory of marine Science and Numerical modeling Qingdao 266061China

Surface waves have a considerable effect on vertical mixing in the upper *** the past two decades,the vertical mixing induced through nonbreaking surface waves has been used in ocean and climate models to improve the simulation of the upper *** far,several nonbreaking wave-induced mixing parameterization schemes have been proposed;however,no quantitative comparison has been performed am.ng *** this paper,a one-dimensional ocean model was used to compare the performances of five schemes,including those of Qiao et al.(Q),Hu and Wang(HW),Huang and Qiao(HQ),Pleskachevsky et al.(P),and Ghantous and Babanin(GB).Similar to previous studies,all of these schemes can decrease the simulated sea surface temperature(SST),increase the subsurface temperature,and deepen the mixed layer,thereby alleviating the common thermal deviation problem of the ocean model for upper ocean *** these schemes,the HQ scheme exhibited the weakest wave-induced mixing effect,and the HW scheme exhibited the strongest effect;the other three schemes exhibited roughly the same *** particular,the Q and P schemes exhibited nearly the same *** the simulation based on observations from the Ocean Weather Station Papa,the HQ scheme exhibited the best performance,followed by the Q *** the experiment with the HQ scheme,the root-mean-square deviation of the simulated SST from the observations was 0.43℃,and the mixed layer depth(mLD)was 2.0 *** a contrast,the deviations of the SST and mLD reached 1.25℃ and 8.4 m,respectively,in the experiment without wave-induced mixing.

关键词： wave-induced mixing surface waves sea surface temperature mixed layer depth General Ocean Turbulence model

A Residual Frequency Offset Estimation method Based on range migration Fitting

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Journal of Beijing Institute of Technology 2024年第2期33卷 103-110页

作者： Liting Zhang Hao Huan ran Tao Xiaogang Tang School of Information and Electronics Beijing Institute of Technology School of Aerospace Information Space Engineering University

Recently, researchers have proposed an emitter localization method based on passive synthetic aperture. However, the unknown residual frequency offset(RFO) between the transmitter and the receiver causes the received Doppler signal to shift, which affects the localization accuracy. To solve this issue, this paper proposes a RFO estimation method based on range migration fitting. Due to the high frequency modulation slope of the linear frequency modulation(LFm)-modulation radar signal, it is not affected by RFO in range compression. Therefore, the azimuth time can be estimated by fitting the peak value position of the pulse compression in range ***, the matched filters are designed under different RFOs. When the zero-Doppler time obtained by the matched filters is consistent with the estimated azimuth time, the given RFO is the real RFO between the transceivers. The simulation results show that the estimation error of azimuth distance does not exceed 20 m when the received signal duration is not less than 3 s, the pulse repetition frequency(PRF) of the transmitter radar signal is not less than 1 k Hz, the range detection is not larger than 1 000 km, and the signal noise ratio(SNR) is not less than –5 d B.

关键词： range migration fitting (RmF) passive localization residual frequency offset (RFO)

In-situ TEm study of the effect of hydrogen-helium ratio on defect characteristics in Fe9Cr1.5W0.4Si F/m steel during H_(2)^(+)&He^(+)simultaneous irradiation

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Journal of materials Science & Technology 2024年第6期173卷 192-201页

作者： Dewang Cui Ziqi Cao Kun He Yuanm.ng Li Xi Qiu Guang ran College of Energy Xiamen UniversityXiamen 361102China Fujian Provincial Nuclear Energy Engineering Technology Research Center Xiamen 361102China Science and Technology on Reactor Fuel and materials Laboratory Chengdu 610041China Nuclear Power Institute of China Chengdu 610041China Science and Technology on Reactor System Design Technology Laboratory Chengdu 610041China

The effect of hydrogen and helium interaction,especially H-He ratio,on the irradiation behavior of nuclear materials has not yet been ***,this is an important basis for evaluating the irradiation properties of nuclear materials and developing high irradiation resistant ***,30 keV H_(2)^(+)and He^(+)dual beams with four H-He ratios of 0:10,3:10,15:10,and 30:10 were used to irradiate the newly developed Fe9Cr1.5W0.4Si F/m steel in TEm to in-situ study the interaction and ratio effect of hydrogen and *** addition of H atoms significantly promoted the nucleation of dislocation loops and *** the early stage of irradiation,the average size and density of dislocation loops increased with the increase of H-He ***,the larger the H-He ratio,the easier it was to form a complex dislocation ***,the final saturation size of bubbles increased with the increase of H-He *** was first found that the swelling was affected by H concentrations,with high H concentrations slowing down the increase in *** a certain irradiation dose,a specific H-He ratio would lead to a swelling peak of Fe9Cr1.5W0.4Si F/m *** super-sized bubbles at grain boundaries(GBs)were found after H addition,resulting in a bigger swelling of GBs than the *** the swelling of the GBs and the matrix show a dependence on the H-He *** current work is of great significance for understanding the interaction between hydrogen and helium in nuclear materials.

关键词： Dose ratio effect Ferritic-martensitic steel Hydrogen&helium synergetic irradiation In-situ TEm

Superhydrophilic nickel hydroxide ultrathin nanosheets enable high-performance asymmetric supercapacitors

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Rare metals 2024年第1期43卷 138-147页

作者： Yi-ran Wang Fei Zhang Jian-min Gu Xiao-Yu Zhao ran Zhao Xing Wang Tian-Hui Wu Jing Wang Ji-Dong Wang De-Song Wang State Key Laboratory of metastable materials Science and Technology(mmST) Hebei Key Laboratory of Applied ChemistryYanshan UniversityQinhuangdao 066004China Department of Food and Pharmaceutical Engineering Suihua UniversitySuihua 152000China School of Chemical Science and Engineering Tongji UniversityShanghai 200092China School of Sciences Hebei University of Science and TechnologyShijiazhuang 050018China

Superhydrophilic surfaces have been applied for supercapacitor;however,during energy storage reaction,how the wettability affects the process of electrochemical reaction specifically is still ***,we demonstrate superhydrophilic surface for promotion of electrochemical reactions by liquid affinity and further explain the mechanism,where the transition of the wettability state caused by the change in surface free energy is the main reason for the obvious increase in specific *** citric acid assistance strategy,an intrinsically hydrophobic Ni(OH)_(2)thick nanosheets(HNHTNs,16 nm)can be transitioned into superhydrophilic Ni(OH)_(2)ultrathin nanosheets(SNHUNs,6.8 nm),where the water contact angle was 0°and the surface free energy increased from 8.6to 65.8 mN·m^(-1),implying *** with HNHTNs,the specific capacitance of SNHUNs is doubled:from 1230 F·g^(-1)(HNHTNs)to 2350 F·g^(-1)(2A·g^(-1))and,even at 20 A·g^(-1),from 833 F·g^(-1)(HNHTNs)to 1670 F·g^(-1).The asymmetric capacitors assembled by SNHUNs and activated carbon show 52.44 Wh·kg^(-1)at 160W·kg^(-1)and excellent stability with~90%retention after5000 cycles(~80%retention after 9500 cycles).The promotion of electrochemical performances is ascribed to the change of surface wettability caused by surface free energy,which greatly increase affinity of electrode to the surrounding liquid environment to reduce the interface resistance and optimize the electron transport path.

关键词： Asymmetric supercapacitor Superhydrophilic interface Transition metal hydroxides Ultrathin nanosheets High specific capacitance

A game-theoretic approach for federated learning:A trade-off am.ng privacy,accuracy and energy

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Digital Communications and Networks 2024年第2期10卷 389-403页

作者： Lihua Yin Sixin Lin Zhe Sun ran Li Yuanyuan He Zhiqiang Hao Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou510006China School of Cyber Science and Engineering Huazhong University of Science and TechnologyWuhan430074China China Industrial Control Systems Cyber Emergency Response Team Beijing100040China

Benefiting from the development of Federated Learning(FL)and distributed communication systems,large-scale intelligent applications become *** devices not only provide adequate training data,but also cause privacy leakage and energy *** to optimize the energy consumption in distributed communication systems,while ensuring the privacy of users and model accuracy,has become an urgent *** this paper,we define the FL as a 3-layer architecture including users,agents and *** order to find a balance am.ng model training accuracy,privacy-preserving effect,and energy consumption,we design the training process of FL as game *** use an extensive game tree to analyze the key elements that influence the players’decisions in the single game,and then find the incentive mechanism that meet the social norms through the repeated *** experimental results show that the Nash equilibrium we obtained satisfies the laws of reality,and the proposed incentive mechanism can also promote users to submit high-quality data in *** the multiple rounds of play,the incentive mechanism can help all players find the optimal strategies for energy,privacy,and accuracy of FL in distributed communication systems.

关键词： Federated learning Privacy preservation Energy optimization Game theory Distributed communication systems

Tuning mechanical and electrical performances of B_(4)C-TiB_(2)ceramics in a two-step spark plasma sintering process

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Journal of Advanced Ceramics 2024年第4期13卷 518-528页

作者： Jun Zhao Xingshuo Zhang Zongning ma Dong Wang Xing Jin Songlin ran Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMaanshan 243002China Anhui Engineering Research Center for High Efficiency Intelligent Photovoltaic module Chaohu UniversityHefei 238024China

B_(4)C–TiB_(2)is an advanced electrically conductive ceramic with excellent mechanical and electrical discharge machinable *** is challenging and rewarding to achieve highly conductive and hard B_(4)C–TiB_(2)composites at a minimum content of conductive TiB2 that has inferior hardness but double specific gravity of the B_(4)C matrix.A novel strategy was used to construct conductive networks in B_(4)C‒15 vol%TiB2 composite ceramics with B_(4)C,TiC,and amorphous B as raw materials by a two-step spark plasma sintering *** influences of particle size matching between B_(4)C and TiC on the conducting of the strategy and the microstructure were discussed based on the selective matrix grain growth *** mechanical and electrical properties were also systematically *** B_(4)C–15 vol%TiB2 composite ceramic prepared from 10.29µm B_(4)C and 0.05µm TiC powders exhibited a perfect three-dimensional interconnected conductive network with a maximum electrical conductivity of 4.25×10^(4)S/m,together with excellent mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 691±58 mPa,30.30±0.61 GPa,and 5.75±0.32 mPa·m^(1/2),respectively,while the composite obtained from 3.12µm B_(4)C and 0.8µm TiC powders had the best mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 827±35 mPa,32.01±0.51 GPa,and 6.45±0.22 mPa·m^(1/2),together with a decent electrical conductivity of 0.65×10^(4)S/m.

关键词： B_(4)C-TiB_(2) mechanical properties electrical conductivity conductive network

Solidification/Stabilization of Chromium in Red mud-based Geopolymer

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Journal of Wuhan University of Technology(materials Science) 2024年第4期39卷 819-830页

作者：田崇霏 LUO Zhongtao LIU Lei LIU Xiaohai 张美香陈萌 HAI ran School of materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Renbang Technology Co. Ltd.Luoyang 471700China School of Water Conservancy and Civil Engineering Zhengzhou UniversityZhengzhou 450001China School of Architectural and Civil Engineering Zhongyuan University of TechnologyZhengzhou 450007China

Up to 1.5wt%of Cr(Ⅲ)salts(CrCl_(3),and Cr_(2)O_(3))and Cr(Ⅵ)salts(Na_(2)CrO_(4),and CaCr_(2)O_(7))were incorporated into red mud-based geopolymers,*** solidification/stabilization,compressive strength,and durability of the Cr-containing geopolymers were *** experimental results indicate that the red mud-based geopolymer could effectively solidify/stabilize different types of Cr salts with solidification/stabilization rates of above 99.61%.Geopolymers are environmentally safe when the dosage of CaCr_(2)O_(7)is≤1.0wt%,or the dosage of CrCl_(3),Cr_(2)O_(3),and Na_(2)CrO_(4)is≤1.5wt%,*** effects of Cr salts on the compressive strength varies with the type and content of Cr *** freeze-thaw cycle is more destructive to geopolymer properties than sulfate attack or acid rain *** solidification/stabilization of Cr is mainly attributed to the following reasons:a)The chemical binding of Cr is related to the formation of Cr-containing hydrates(eg,magnesiochromite((mg,Fe)(Cr,Al)_(2)O_(4)))and doping into N-A-S-H gel and C-A-S-H gel framework;b)The physical effect is related to the encapsulation by the hydration products(e g,N-A-S-H gel and C-A-S-H gel).This study provides a reference for the treatment of hazardous Cr-containing wastes by solid waste-based geopolymers.

关键词： chromium solidification/stabilization geopolymer red mud durability

Nab-paclitaxel plus capecitabine as first-line treatment for advanced biliary tract cancers:An open-label,non-randomized,phase II clinical trial

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World Journal of Gastroenterology 2024年第30期30卷 3564-3573页

作者： Ling-Xiao Xu Jia-Jia Yuan ran Xue Jun Zhou Department of Gastrointestinal Oncology Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing)Peking University Cancer Hospital and InstituteBeijing 100142China

BACKGROUND Biliary tract cancers(BTCs)are a heterogeneous group of tumors with high malignancy,poor prognosis,and limited treatment *** To explore the efficacy and safety of nab-paclitaxel plus capecitabine as first-line treatment for advanced and metastatic *** This open-label,non-randomized,double-center,phase II clinical trial recruited systemic therapy-naive patients with unresectable or metastatic BTCs between April 2019 and June 2022 at Beijing Cancer Hospital and the First Hospital of China medical *** patients were administered nab-paclitaxel(150 mg/m^(2),day 1)and capecitabine(2000 mg/m^(2),twice daily,days 1-7)in 14-day cycles until experiencing intolerable toxicity or disease *** primary outcome was the objective response rate(ORR).The secondary outcomes included the disease control rate(DCR),overall survival(OS),progression-free survival(PFS),and *** A total of 44 patients successfully completed the trial,with a median age of 64.00 years(interquartile range,35.00-76.00),and 26(59.09%)were *** response assessment was impeded for one patient due to premature demise from tumor *** the remaining 43 patients undergoing at least one imaging assessment,the ORR was 23.26%[95%confidence interval(CI):11.80%-38.60%],and the DCR was 69.77%(95%CI:53.90%-82.80%).The median OS was 14.1 months(95%CI:8.3-19.9),and the median PFS was 4.4 months(95%CI:2.5-6.3).A total of 41 patients(93.18%)experienced at least one adverse event(AE),with 10 patients(22.73%)encountering grade≥3 AEs,and the most frequent AEs of any grade were alopecia(79.50%),leukopenia(54.55%),neutropenia(52.27%),and liver dysfunction(40.91%),and no treatment-related deaths were *** Nab-paclitaxel plus capecitabine may be an effective and safe first-line treatment strategy for patients with advanced or metastatic BTCs.

关键词： Nab-paclitaxel Capecitabine Biliary tract cancer Objective response rate Phase II clinical trial