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Audio-Text Multimodal Speech Recognition via Dual-Tower Architecture for Mandarin Air Traffic Control Communications

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Computers, Materials & Continua 2024年第3期78卷 3215-3245页

作者： Shuting Ge Jin Ren Yihua Shi yujun zhang Shunzhi Yang Jinfeng Yang School of Computer Science and Software Engineering University of Science and Technology LiaoningAnshan114051China Institute of Applied Artificial Intelligence of the Guangdong-Hong Kong-Macao Greater Bay Area Shenzhen Polytechnic UniversityShenzhen518055China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen518055China Industrial Training Centre Shenzhen Polytechnic UniversityShenzhen518055China

In air traffic control communications (ATCC), misunderstandings between pilots and controllers could result in fatal aviation accidents. Fortunately, advanced automatic speech recognition technology has emerged as a promising means of preventing miscommunications and enhancing aviation safety. However, most existing speech recognition methods merely incorporate external language models on the decoder side, leading to insufficient semantic alignment between speech and text modalities during the encoding phase. Furthermore, it is challenging to model acoustic context dependencies over long distances due to the longer speech sequences than text, especially for the extended ATCC data. To address these issues, we propose a speech-text multimodal dual-tower architecture for speech recognition. It employs cross-modal interactions to achieve close semantic alignment during the encoding stage and strengthen its capabilities in modeling auditory long-distance context dependencies. In addition, a two-stage training strategy is elaborately devised to derive semantics-aware acoustic representations effectively. The first stage focuses on pre-training the speech-text multimodal encoding module to enhance inter-modal semantic alignment and aural long-distance context dependencies. The second stage fine-tunes the entire network to bridge the input modality variation gap between the training and inference phases and boost generalization performance. Extensive experiments demonstrate the effectiveness of the proposed speech-text multimodal speech recognition method on the ATCC and AISHELL-1 datasets. It reduces the character error rate to 6.54% and 8.73%, respectively, and exhibits substantial performance gains of 28.76% and 23.82% compared with the best baseline model. The case studies indicate that the obtained semantics-aware acoustic representations aid in accurately recognizing terms with similar pronunciations but distinctive semantics. The research provides a novel modeling paradigm for semantics-aware speech recognition in

关键词： Speech-text multimodal automatic speech recognition semantic alignment air traffic control communications dual-tower architecture

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Swin-PAFF: A SAR Ship Detection Network with Contextual Cross-Information Fusion

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Computers, Materials & Continua 2023年第11期77卷 2657-2675页

作者： yujun zhang Dezhi Han Peng Chen School of Information Engineering Shanghai Maritime UniversityShanghai201306China

Synthetic Aperture Radar(SAR)image target detection has widespread applications in both military and civil domains.However,SAR images pose challenges due to strong scattering,indistinct edge contours,multi-scale representation,sparsity,and severe background interference,which make the existing target detection methods in low accuracy.To address this issue,this paper proposes a multi-scale fusion framework(Swin-PAFF)for SAR target detection that utilizes the global context perception capability of the Transformer and the multi-layer feature fusion learning ability of the feature pyramid structure(FPN).Firstly,to tackle the issue of inadequate perceptual image context information in SAR target detection,we propose an end-to-end SAR target detection network with the Transformer structure as the backbone.Furthermore,we enhance the ability of the Swin Transformer to acquire contextual features and cross-information by incorporating a Swin-CC backbone network model that combines the Spatial Depthwise Pooling(SDP)module and the self-attentive mechanism.Finally,we design a cross-layer fusion neck module(PAFF)that better handles multi-scale variations and complex situations(such as sparsity,background interference,etc.).Our devised approach yields a noteworthy AP@0.5:0.95 performance of 91.3%when assessed on the HRSID dataset.The application of our proposed technique has resulted in a noteworthy advancement of 8%in the AP@0.5:0.95 scores on the HRSID dataset.

关键词： Transformer deep learning SAR object detection ship detection

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Enhanced secondary organic aerosol formation during dust episodes by photochemical reactions in the winter in Wuhan

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Journal of Environmental Sciences 2023年第11期133卷 70-82页

作者： Kai Xu Yafei Liu Chenlu Li Chen zhang Xingang Liu Qijie Li Min Xiong yujun zhang Shijie Yin Yu Ding State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Wuhan Municipality Environmental Monitoring Center Wuhan 430015China College of Environment and Ecology Chongqing UniversityChongqing 400030China

To investigate the effect of frequently occurring mineral dust on the formation of secondary organic aerosol(SOA),106 volatile organic compounds(VOCs),trace gas pollutants and chemical components of PM_(2.5) were measured continuously in January 2021 in Wuhan,Central China.The observation period was divided into two stages that included a haze period and a following dust period,based on the ratio of PM_(2.5) and PM_(10) concentrations.The average ratio of secondary organic carbon(SOC)to elemental carbon(EC)was 1.98 during the dust period,which was higher than that during the haze period(0.69).The contribution of SOA to PM_(2.5) also increased from 2.75% to 8.64%.The analysis of the relationships between the SOA and relative humidity(RH)and the odd oxygen(e.g.,O_(X)=O_(3)+NO_(2))levels suggested that photochemical reactions played a more important role in the enhancement of SOA production during the dust period than the aqueous-phase reactions.The heterogeneous photochemical production of OH radicals in the presence of metal oxides during the dust period was believed to be enhanced.Meanwhile,the ratios of trans-2-butene to cis-2-butene and m-/p-xylene to ethylbenzene(X/E)dropped significantly,confirming that stronger photochemical reactions occurred and SOA precursors formed efficiently.These results verified the laboratory findings that metal oxides in mineral dust could catalyse the oxidation of VOCs and induce higher SOA production.

关键词： VOCs Mineral dust Metal oxides SOA Photochemical reactions

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Embryonic expression and evolutionary analysis of the amphioxus Dickkopf and Kremen family genes

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Journal of Genetics and Genomics 2010年第9期37卷 637-645页

作者： yujun zhang Bingyu Mao State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The secreted Wnt signaling inhibitor Dickkopfl （Dkkl） plays key role in vertebrate head induction. Its receptor Kremen synergizes with Dkkl in Wnt inhibition. Here we have carried out expression and functional studies of the Dkk and Kremen genes in amphioxus （Branchiostoma belcheri）. During embryonic and larval development, BbDkkl/2/4 is expressed in the posterior mesoendoderm, anterior somatic mesoderm and the pharyngeal regions. Its expression becomes restricted to the pharyngeal region on the left side at larval stages. In 45 h larvae, BbDkkl/2/4 is expressed specifically in the cerebral vesicle. BbDkk3 was only detected at larval stages in the mid-intestine region. Seven Kremen related genes were identified in the genome of the Florida amphioxus （Branchiostoma floridae）, clustered in 4 scaffolds, and are designated Kremenl-4 and Kremen-like 1-3, respectively. In B. belcheri, Kremenl is strongly expressed in the mesoendoderm during early development and Kremen3 is expressed asymmetrically in spots in the larval pharyngeal region. In luciferase reporter assays, BbDkkl/2/4 can strongly inhibit Wnt signaling, while BbDkk3, BbKremenl and BbKremen3 can not. No co-operative effect was observed between amphioxus Dkkl/2/4 and Kremens, suggesting that the interaction between Dkk and Kremen likely originated later during evolution.

关键词： amphioxus Dickkopf Kremen evolution expression pattern

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FEM ANALYSIS FOR INFLUENCES OF A FAULT ON COUPLED T-H-M-M PROCESS IN DUAL-POROSITY ROCK MASS

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Acta Mechanica Solida Sinica 2012年第6期25卷 651-662页

作者： yujun zhang Chaoshuai Yang Gang Xu State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics The Chinese Academy of Sciences Technology Centre China Railway Tunnel Group Co. Ltd

For the case in which a large geological structure like fault existing within the surrounding rock mass in the near field of a repository for high-level radioactive nuclear waste, one kind of coupled thermo-hydro-mechanical-migratory model of dual-porosity medium for saturated- unsaturated ubiquitous-joint rock mass was established. In the present model, the seepage field and the concentration field are double, but the stress field and the temperature field are single, and the influences of sets, spaces, angles, continuity ratios, stiffness of fractures on the constitutive relationship of the medium can be considered. At the same time, a two-dimensional program of finite element method was developed. Taking a hypothetical nuclear waste repository located at a rock mass being unsaturated dual-porosity medium as a calculation example, the FEM analysis for thermo-hydro-mechanical-migratory coupling were carried out under the condition of radioac- tive nuclide leaking for the cases with and without a fault, and the temperatures, pore pressures, flow velocities, nuclide concentrations and principal stresses in the rock mass were investigated. The results show that the fracture water in the fault flows is basically along the fault direction, and its flow velocity is almost three orders of magnitude higher than that of fracture water in rock mass; the nuclide concentration in the fault is also much higher than that without fault, and the nuclides move along the fault faster; moreover, the fault has obvious influences on the pore pressures and the principal stresses in the rock mass.

关键词： fault dual-porosity medium thermo-hydro-mechanical-migratory coupling FEManalysis

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Influence of Gas Temperature on Microstructure and Properties of Cold Spray 304SS Coating

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Journal of Materials Science & Technology 2011年第9期27卷 809-815页

作者： Xianming Meng Junbao zhang Jie Zhao Yongli Liang yujun zhang School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China Baosteel Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

In the present study, 304 stainless steel coatings were deposited on interstitial-free steel substrates by cold gas dynamic spray technology. The effect of gas temperature on microstructure, micro-hardness, cohesive strength, and electrochemical property of the coatings were investigated and compared. The results showed that increasing gas temperature had a great contribution to enhancing the bonding strength between the deposited particles and making the microstructure more density. Therefore, the porosity of the coatings decreased from 0%4-0.5% to 2%4-0.3%, and the tensile strength of the coatings increased from 564-4 MPa up to 734-3 MPa. In addition, the corrosion resistance of the coatings was also deeply influenced by process gas temperature. The corrosion kinetics of the coatings were affected by both of the plastic deformation of deposited particles and the porosity in the coatings.

关键词： Cold spray Gas temperature 304 stainless steel coating Microstructure Property

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坚硬主控覆岩预裂弱化控制导水裂缝带高度机制研究

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岩石力学与工程学报 2024年第S1期43卷 3363-3373页

作者：张玉军肖杰李友伟宋业杰煤炭科学研究总院开采研究院北京100013 中煤科工开采研究院有限公司北京100013 天地科技股份有限公司开采设计事业部北京100013 煤炭智能开采与岩层控制全国重点实验北京100013

煤矿顶板水害防控与水资源保护的核心是控制导水裂缝带发育高度,降低煤层开采对上覆含水层扰动。基于覆岩破坏控制技术和顶板预裂弱化控制矿山压力显现方面研究现状,提出通过主动预裂弱化坚硬主控岩层,在不影响开采效率和资源回收率的... 详细信息

煤矿顶板水害防控与水资源保护的核心是控制导水裂缝带发育高度,降低煤层开采对上覆含水层扰动。基于覆岩破坏控制技术和顶板预裂弱化控制矿山压力显现方面研究现状,提出通过主动预裂弱化坚硬主控岩层,在不影响开采效率和资源回收率的情况下控制采动导水裂缝带发育高度的低损害开采技术构想。采用相似模拟,理论分析和数值模拟分析相结合的研究方法探究预裂弱化坚硬主控岩层控制导水裂缝带发育高度作用机制,并根据数值模拟结果提出含水层下坚硬覆岩预裂层位确定方法。研究结果表明:坚硬岩层相较于软弱岩层采动破断块度较大,采动破坏后整齐堆积于采空区,采动破坏膨胀量较小;不同层位坚硬岩层预裂弱化条件下采动响应存在显著差异,因此预裂层位选择将直接决定预裂弱化控制导水裂缝带高度效果;数值模拟结果显示中位岩层预裂和中、低位岩层同时预裂时导水裂缝带发育高度控制效果较好。研究成果为含水层下煤炭资源安全、高效和绿色开采提供了新的技术途径。

关键词：采矿工程导水裂缝带控制预裂弱化坚硬主控岩层水害防治水资源保护

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A Decoupling Control Model on Perturbation Method for Twin-Roll Casting Magnesium Alloy Sheet

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Journal of Materials Science & Technology 2015年第5期31卷 517-522页

作者： Wenyu zhang Dongying Ju Hongyang Zhao Xiaodong Hu Yao Yao yujun zhang School of Software University of Science and Technology Liaoning School of Materials and Metallurgy University of Science and Technology Liaoning School of Mechanical Engineering and Automation University of Science and Technology Liaoning

To better understand the twin-roll casting process,based on the analysis of the solidification phenomenon,the geometry shape of the molten metal pool,the continuity of metal and the balance of energy and momentum,five critical partial equations were established separately including the equations of pool level,solidification process,roll separating force,roll gap and casting speed.Meanwhile,to obtain a uniform sheet thickness and keep a constant roll separating force,a decoupling control model was built on the perturbation method to eliminate the interference of process parameters.The simulation results show that the control model is valuable to quickly and accurately determine the control parameters.Moreover,Mg alloy sheets with high quality were cast by applying this model.

关键词： Twin-roll casting Decoupling control model Perturb

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Enhanced Fracture Toughness of Pressureless-sintered SiC Ceramics by Addition of Graphene

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Journal of Materials Science & Technology 2016年第7期32卷 633-638页

作者： Qisong Li yujun zhang Hongyu Gong Haibin Sun Wenjie Li Li Ma Yanshuang zhang Key Laboratory for Liquid-Solid Structural Evolution & Processing of Materials of Ministry of Education Shandong University School of Materials and Chemical Engineering Zhongyuan University of Technology Key Laboratory of Special Functional Aggregated Materials Ministry of Education Shandong University Shandong Baona New Materials Co. Ltd.

To enhance the fracture toughness of pressureless-sintered SiC ceramic, graphene was introduced as an additive. The effects of graphene contents on the fracture toughness, bending strength, micro-hardness, phase compositions, and microstructure evolutions of the SiC ceramics were investigated in detail by scanning electron microscopy, energy dispersive X-ray spectroscopy, and metallographic microscopy. The fracture toughness, bending strength and micro-hardness increased initially, and then decreased with the graphene content increasing from 0 to 5.0 wt%. The highest fracture toughness of 5.65 MPa m1/2 was obtained for sample with 1.0 wt% graphene sintered at 2130 ℃ for 1 h in At, which was about 22.6% higher than that of SiC sample without graphene. In addition, the highest bending strength and microhardness of 434.14 MPa and 29.21 GPa corresponded to the SiC samples with graphene content of 0.5 wt% and 2.0 wt%, respectively.

关键词： SiCGrapheneFracture toughnessBending strengthMicro-hardness

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坚硬覆岩预裂弱化改性效应及导水裂缝带控制机理

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煤炭科学技术 2024年第4期52卷 105-118页

作者：张玉军李友伟肖杰张志巍李嘉伟中煤科工开采研究院有限公司北京100013 天地科技股份有限公司开采设计事业部北京100013 煤炭资源高效开采与洁净利用国家重点实验室北京100013 煤炭科学研究总院开采研究院北京100013

针对深部煤层开采坚硬覆岩条件下导水裂缝带控制问题,充分借鉴坚硬顶板预裂弱化技术,提出预裂弱化坚硬主控覆岩控制导水裂缝带高度的新方法。综合采用实验室试验、理论分析、数值模拟等方法,研究了坚硬主控覆岩预裂弱化改性效应,详细阐... 详细信息

针对深部煤层开采坚硬覆岩条件下导水裂缝带控制问题,充分借鉴坚硬顶板预裂弱化技术,提出预裂弱化坚硬主控覆岩控制导水裂缝带高度的新方法。综合采用实验室试验、理论分析、数值模拟等方法,研究了坚硬主控覆岩预裂弱化改性效应,详细阐述了不同弱化层位对导水裂缝带的控制机理,并进行了实测验证。研究结果表明:预制裂缝可以使坚硬岩石往强度低的方向进行转变,并将完整岩样的劈裂破坏特征转变为以预制裂缝为主控的张拉剪切破坏,坚硬岩石的破坏程度由剧烈趋于缓和;揭示了预制裂缝对坚硬岩体的弱化改性效应,计算得到应力与裂缝耦合的损伤变量,定性的分析了弱化程度与岩性转变的关系,改性后岩体能量存储能力降低,耗散能力增强;数值模拟了不同弱化层位对导水裂缝带的控制效果,综合对比覆岩破坏形态、裂隙数量及破坏高度动态演化规律,发现“马鞍形”破坏形态随着弱化层位的升高而逐渐减弱,覆岩裂隙数量演化基本呈现“缓增−突增”的演化趋势,未弱化以及中、高位弱化覆岩破坏高度动态演化近似呈现“S”形,而中位弱化呈“半抛形”,综合分析得出低位弱化对导水裂缝带的控制效果最好;在分析高、中、低位坚硬岩层破坏特征的基础上,揭示了不同预裂弱化层位控制导水裂缝带发育机理;钻孔实测孟村矿顶板压裂条件下的“两带”发育高度,对比发现预裂弱化条件下裂采比降低,初步验证了顶板预裂弱化对导水裂缝带发育的抑制性。研究成果将为深部矿区耦合灾害防控、水资源及生态保护等领域提供理论和科学依据。

关键词：坚硬覆岩预裂弱化岩层控制导水裂缝带高度改性效应

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