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一种基于FL-TransCNN神经网络的水声智能频谱感知算法

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电讯技术 2025年

作者：李玉芳王锴张力良徐凌伟 Gulliver ta 青岛科技大学信息科学技术学院数字化学习技术集成与应用教育部工程研究中心加拿大维多利亚大学电子与计算机工程学院

海洋通信装备间产生的海量数据导致水声频谱资源紧张，亟需提高水声频谱利用率以满足信息传递需求。因此，一种基于联邦学习（Federated Learning， FL）、Transformer和卷积神经网络（Convolutional Neural Networks， CNN）的水声智... 详细信息

海洋通信装备间产生的海量数据导致水声频谱资源紧张，亟需提高水声频谱利用率以满足信息传递需求。因此，一种基于联邦学习（Federated Learning， FL）、Transformer和卷积神经网络（Convolutional Neural Networks， CNN）的水声智能频谱感知算法被提出，以提高频谱利用率。首先，基于FL实现数据隔离状态下的信息共享，并应用Paillier加密技术进行权重加密保障。其次，本地感知数据经连续小波变换构建为时频谱图。最后，融合CNN与Transformer构建了TransCNN感知器，通过并行分支实现了高精度感知。TransCNN感知器包含预处理表征模块和并行分支表征模块；其中，预处理表征模块利用深度可分离卷积改进了Transformer以处理时频谱图，增强了自注意力机制对局部特征的建模能力；并行分支表征模块联合了Transformer、卷积层、池化层等执行两路差异表征，然后融合两路特征，可以聚焦更细微的关键特征，实现高精度水声智能频谱感知技术。在信噪比-18～0 dB范围内，与RepVGG、Swin-transformer、YOLOv7、MobileNet算法相比，基于FL-TransCNN神经网络的水声智能频谱感知算法的平均检测概率提升了4%～10%，平均虚警概率降低了2%～9%。

关键词：海洋物联网频谱感知联邦学习连续小波变换深度可分离卷积

Fluid dynamics analysis and pyrolysis of brewer’s spent grain in a spouted bed reactor

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Particuology 2019年第1期17卷 199-207页

作者： Marcos A.S. Barrozo Lidja D.M.S. Borel taísa S. Lira Carlos H. Ataíde School of Chemical Engineering Federal University of UberlandiaBrazil Department of Engineering and Technologies Federal University of Espirito SantoBrazil

Brewer’s spent grain (BSG) is a large-scale agroindustrial waste that could be more efficiently utilized. This waste is composed of lignocellulosic material and so may serve as a good source of biomass for thermochemical conversion. The present study investigated the fluid dynamics behavior of mixtures of sand and BSG in a spouted bed to assess the viability of the thermochemical conversion of this biomass via fast pyrolysis. Fluid dynamics analyses were performed while varying the mass fraction of BSG (6–80%) and the static bed height (6.6–13.4 cm). Empirical equations for predicting the minimum spouting conditions and the mixing index were obtained using a regression technique, and the selected fluid dynamics parameters were employed in the spouted bed pyrolysis. The bio-oil resulting from this process was rich in phenolic compounds, various nitrogenated compounds (representing precursors for pharmaceuticals) and long-chain hydrocarbons. The products obtained from the analytical and spouted bed pyrolysis processes were also compared.

关键词： Brewer’s spent grain Agroindustrial residue Spouted bed Fast pyrolysis Particle mixing

DETerMINATION OF RADON AND NATURAL RADIOACTIVITY CONCENTRATION IN SOME BUILDING MATerIALS USED IN IZMIR,TURKEY

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Journal of Green Building 2020年第1期15卷 107-118页

作者： Daniel hatungimana Caner taşköprü Mutlu İçhedef Müslim Murat saç Şemsi Yazıcı Ali Mardani-Aghabaglou Department of Civil Engineering Eng.FacultyEge UniversityBornova-IzmirTurkey Institute of Nuclear Sciences Ege UniversityBornova-IzmirTurkey Department of Civil Engineering Eng.FacultyBursa UludağUniversityNilüfer-BursaTurkey Civil Engineering Department University of Burundi2700 BujumburaBurundi

The aim of this study is to determine the radon and natural radioactivity concentra-tions of some building materials and to assess the radiation hazard associated with those mortar materials when they are used in the construction of *** measurements were realized by using LR-115 Type 2 solid state nuclear track *** activity concentrations of these materials were found to vary between 130.00±11.40 and 1604.06±40.5 Bq m^(-3).The natural radioactivity in selected mortar materials was analyzed by using scintillation gamma *** activity concentrations for 226Ra,232Th and 40K for the studied mortar materials ranged from ND to 48.5±7.0 Bq kg^(-1),ND to 41.0±6.4 Bq kg^(-1)and ND to 720.4±26.8 Bq kg^(-1),*** equivalent activities,external and internal hazard indexes,gamma and alpha indexes and absorbed gamma dose rates were calculated to assess the radiation hazard of the natural radioactivity in studied *** calculated Raeq values of all samples were found to be lower than the limit of 370 Bq kg-1 set for building *** estimated hazard index values were found to be under the unity and the absorbed dose rate values were also below the worldwide average of 84 nGy h^(-1).

关键词： Radium activity solid state nuclear track detector hazard index absorbed dose rate

Oxidation behavior of multi-component ta-W-Al-Ti alloy at 1173 K

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Rare Metals 2021年第7期40卷 1940-1948页

作者： Jia-Xin Li Yu-Hong Chen Zhang-Jun Bai Bao-Jun Zhao Liang Jiang Lan-er Wu School of Materials Science and Engineering North Minzu UniversityYinchuan 750021China CNMC Ningxia Orient Group Co.Ltd Shizuishan 753000China School of Chemical Engineering The University of QueenslandBrisbaneQLD 4072Australia

ta-W alloys have unique properties but their applications at high temperatures are restricted due to their poor oxidation *** addition of Al and Ti decreases the oxidation rate of the alloy,as Al-contained protective oxide layer could be *** this study,ternary and quaternary ta-W alloys containing Al and Ti were prepared by hot press *** microstructures and oxidation behaviors of the alloys were studied at1173 *** results show that the oxidation kinetics of all alloys follows a parabolic law at short oxidation *** cyclic oxidation,the kinetics of quaternary alloys still obeys the parabolic law but that of ternary alloy has been changed into linear law kinetics after 8-h *** ternary alloy,an outer layer with dense and continuous alumina was formed during the initial stage,and phase transformation caused the oxides to peel *** comparison,the quaternary alloys depicted continuously solid solution of the oxides ***,Al and Ti played key roles in oxidation degree and affected the oxidation kinetics of ternary and quaternary alloys.

关键词： Oxidation behavior ta-W-based alloy Aluminum Titanium

Impact of chosen force fields and applied load on thin film lubrication

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Friction 2021年第5期9卷 1259-1274页

作者： Thi D.ta Hien D.ta Kiet A.TIEU Bach H.TRAN School of Mechanical MaterialsMechatronicsand Biomedical EngineeringUniversity of WollongongNSW 2522Australia Ho Chi Minh City University of Technology and Education Ho Chi Minh City 800010Vietnam

The rapid development of molecular dynamics(MD)simulations,as well as classical and reactive atomic potentials,has enabled tribologists to gain new insights into lubrication performance at the fundamental ***,the impact of adopted potentials on the rheological properties and tribological performance of hydrocarbons has not been researched *** extensive study analyzed the effects of surface structure,applied load,and force field(FF)on the thin film lubrication of *** lubricant film became more solid‐like as the applied load *** particular,with increasing applied load,there was an increase in the velocity slip,shear viscosity,and *** degree of ordering structure also changed with the applied load but rather *** was also significantly dependent on the surface *** chosen FFs significantly influenced the lubrication performance,rheological properties,and molecular *** adaptive intermolecular reactive empirical bond order(AIREBO)potential resulted in more significant liquid‐like behaviors,and the smallest velocity slip,degree of ordering structure,and shear stress were compared using the optimized potential for liquid simulations of united atoms(OPLS‐UAs),condensed‐phase optimized molecular potential for atomic simulation studies(COMPASS),and ***,classical potentials,such as OPLS‐UA and COMPASS,exhibit more solid‐like behavior than reactive potentials ***,owing to the solid‐like behavior,the lubricant temperatures obtained from OPLS‐UA and COMPASS were much lower than those obtained from AIREBO and *** increase in shear stress,as well as the decrease in velocity slip with an increase in the surface potential parameterζ,remained conserved for all chosen FFs,thus indicating that the proposed surface potential parameterζfor the COMPASS FF can be verified for a wide range of atomic models.

关键词： molecular dynamics simulation force fields applied load tribofilm hydrocarbon

Unit-cell design for two-dimensional phase-field simulation of microstructure evolution in single-crystal Ni-based superalloys during solidification

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Progress in Natural Science:Materials International 2017年第6期27卷 678-686页

作者： Dongjia Cao Na ta Lijun Zhang State Key Lab of Powder Metallurgy Central South University Interdisciplinary Centre for Advanced Materials Simulation (ICAMS) Ruhr-University Bochum

Phase-field simulation serves as an effective tool for quantitative characterization of microstructure evolution in single-crystal Ni-based superalloys during solidification nowadays. The classic unit cell is either limited to γdendrites along crystal orientation or too ideal to cover complex morphologies for γ dendrites. An attempt to design the unit cell for two-dimensional(2-D) phase-field simulations of microstructure evolution in single-crystal Ni-based superalloys during solidification was thus performed by using the MICRESS(MICRostructure Evolution Simulation Software) in the framework of the multi-phase-field(MPF) model,and demonstrated in a commercial TMS-113 superalloy. The coupling to CALPhaD(CALculation of Phase Diagram) thermodynamic database was realized via the TQ interface and the experimental diffusion coefficients were utilized in the simulation. Firstly, the classic unit cell with a single γ dendrite along crystal orientation was employed for the phase-field simulation in order to reproduce the microstructure ***, such simple unit cell was extended into the cases with two other different crystal orientations, i.e., and . Thirdly, for crystal orientations, the effect of γ dendritic orientations and unit cell sizes on microstructure and microsegregation was comprehensively studied, from which a new unit cell with multiple γdendrites was proposed. The phase-field simulation with the newly proposed unit cell was further performed in the TMS-113 superalloy, and the microstructure features including the competitive growth of γ dendrites,microsegregation of different solutes and distribution of γ′ grains, can be nicely reproduced.

关键词： Ni-based superalloys Solidification Microstructure Phase-field simulation Unit cell

Effects of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 on the peroxidase-catalyzed oxidation of 2-naphthol

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Journal of Environmental Sciences 2013年第7期25卷 1431-1440页

作者： Ivanec-Goranina Rūta Kulys Juozas Department of Chemistry and Bioengineering Faculty of Fundamental Sciences Vilnius Gediminas Technical University Institute of Biochemistry Vilnius University

The kinetics of the recombinant Coprinus cinereus peroxidase-catalyzed2-naphthol oxidationwas investigated in the presence of rhamnolipid biosurfactant JBR425 and synthetic surfactant Surfynol465 at pH 5.5 and25°C,with concentrations of （bio）surfactants both less than critical micelle concentrations （CMC） and larger than CMC. Itwas shown that monomers of JBR425 aswell as monomers of Surfynol465 had an enhancing effect on the conversion of2-naphthol indose response manner anddid not influence the initial rate of 2-naphthol oxidation. The resultswere accounted by a scheme,which contains a stadium of enzyme inhibition by oligomeric2- naphthol oxidation products. The action of the biosurfactant＇s （or synthetic surfactant＇s） monomerswas explained by avoidance of the enzyme active center clothingwith oligomers. Similar results havedemonstrated the potential of rhamnolipid biosurfactant JBR425due to its biodegradability. When biosurfactants＇ concentrations are larger than CMC, （bio）surfactants have an opposite effect on the oxidation of2-naphthol by peroxidase.

关键词： oxidation peroxidase biosurfactant critical micelle concentration

Soil Respiration, Microbial Biomass and Nutrient Availability in Soil After Addition of Residues with Adjusted N and P Concentrations

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Pedosphere 2017年第1期27卷 76-85页

作者： Trung ta NGUYEN Petra MARSCHNer School of Agriculture Food and Wine The University of Adelaide Adelaide 5005 (Australia)

Microbial activity and nutrient release are known to be influenced by organic matter properties,but it is difficult to separate the effect of C/N ratio from that of C/P ratio because in most plant residues both ratios are either high or *** incubation experiment was conducted to investigate the effects of reducing the C/N and C/P ratios of slowly decomposable plant residues(young eucalyptus leaves,mature wheat straw,and sawdust) to those of rapidly decomposable residues(young kikuyu shoots) on soil respiration,microbial biomass,and N and P *** C/N and C/P ratios of the former were adjusted to 15 and 89,respectively,by adding N as(NH_4)_2SO_4,P as KH_2PO_4 or both and residues were added at 10 g C kg-1 to a silt *** respiration was measured over21 d;microbial biomass C(MBC) and available N and P were measured on days 0,7,and *** to the unamended soil,addition of kikuyu increased cumulative respiration 20-fold,MBC concentration 4 to 8-fold,and available P concentration up to4-fold,whereas the increase in available N concentration was small and *** respiration and MBC concentration were low in the sawdust-amended soil and were not influenced by reducing the C/N and C/P *** respiration with original wheat and eucalyptus was 30%-40%of that with *** the C/N ratio alone or both C/N and C/P ratios increased cumulative respiration and MBC concentration 2-fold compared to the original wheat and eucalyptus,whereas reducing the C/P ratio had little *** the experiment,the available N concentration after addition of residues with reduced C/N ratio increased in the following order of eucalyptus ering the C/N and C/P ratios,microbial activity was more limited by C and N than ***,lowering the C/N ratio of very slowly decomposable sawdust had no effect on soil respiration and MBC concentration,suggesting that other properties such as concentration of poor

关键词： C/N ratio C/P ratio microbial activity nutrient immobilisation nutrient mineralisation

Sorption of Water-Extractable Organic Carbon in Various Clay Subsoils: Effects of Soil Properties

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Pedosphere 2016年第1期26卷 55-61页

作者： Trung ta NGUYEN Petra MARSCHNer School of Agriculture Food and Wine The University of Adelaide

Clay-rich subsoils are added to sandy soils to improve crop yield and increase organic carbon （C） sequestration; however, little is known about the influence of clay subsoil properties on organic C sorption and desorption. Batch sorption experiments were conducted with nine clay subsoils with a range of properties. The clay subsoils were shaken for 16 h at 4 ℃with water-extractable organic C （WEOC, 1 224 g C L-1） from mature wheat residue at a soil to extract ratio of 1：10. After removal of the supernatant, the residual pellet was shaken with deionised water to determine organic C desorption. The WEOC sorption was positively correlated with smectite and illite contents, cation exchange capacity （CEC） and total organic C, but negatively correlated with kaolinite content. Desorption of WEOC expressed as a percentage of WEOC sorbed was negatively correlated with smectite and illite contents, CEC, total and exchangeable calcium （Ca） concentrations and clay content, but positively correlated with kaolinite content. The relative importance of these properties varied among soil types. The soils with a high WEOC sorption capacity had medium CEC and their dominant clay minerals were smectite and illite. In contrast, kaolinite was the dominant clay mineral in the soils with a low WEOC sorption capacity and low-to-medium CEC. However, most soils had properties which could increase WEOC sorption as well as those that could decrease WEOC sorption. The relative importance of properties increasing or decreasing WEOC sorption varied with soils. The soils with high desorption had a low total Ca concentration, low-to-medium CEC and low clay content, whereas the soils with low desorption were characterised by medium-to-high CEC and smectite and illite were the dominant clay minerals. We conclude that WEOC sorption and desorption depend not on a single property but rather a combination of several properties of the subsoils in this study.

关键词： cation exchange capacity, clay mineral illite, kaolinite smectite