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Sub-Nyquist sampling-based wideband spectrum sensing:a compressed power spectrum estimation approach

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Frontiers of Computer Science 2024年第2期18卷 139-145页

作者： jilin WANG Yinsen HUANG Bin WANG National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In this paper,we introduce a sub-Nyquist sampling-based receiver architecture and method for wideband spectrum *** of recovering the original wideband analog signal,the proposed method aims to directly reconstruct the power spectrum of the wideband analog signal from sub-Nyquist *** that power spectrum alone is sufficient for wideband spectrum *** only the covariance matrix of the wideband signal is needed,the proposed method,unlike compressed sensing-based methods,does not need to impose any sparsity requirement on the frequency *** proposed method is based on a multi-coset sampling *** exploiting the inherent sampling structure,a fast compressed power spectrum estimation method whose primary computational task consists of fast Fourier transform(FFT)is *** results are presented to show the effectiveness of the proposed method.

关键词： wideband spectrum sensing sub-Nyquist multicoset sampling FCPSE

Towards advanced zinc anodes by interfacial modification strategies for efficient aqueous zinc metal batteries

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Journal of Energy Chemistry 2024年第6期93卷 79-110,I0003页

作者： changchun Fan Weijia Meng Jiaye Ye Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology Ministry of EducationSchool of ChemistryBeihang UniversityBeijing 100191China Shaanxi Key Laboratory of New Transportation Energy and Automotive Energy Saving School of Energy and Electrical EngineeringChang’an UniversityXi’an 710061ShaanxiChina School of Chemistry and Physics Faculty of ScienceQueensland University of TechnologyBrisbaneQLD 4001Australia Centre for Materials Science Queensland University of TechnologyBrisbaneQLD 4001Australia

Developing sustainable and clean energy sources(e.g.,solar,wind,and tide energy)is essential to achieve the goal of carbon *** to the discontinuous and inco nsistent nature of common clean energy sources,high-performance energy storage technologies are a critical part of achieving this *** zinc metal batteries(AZMBs)with inherent safety,low cost,and competitive performance are regarded as one of the promising candidates for grid-scale energy ***,zinc metal anodes(ZMAs)with irreversible problems of dendrite growth,hydrogen evolution reaction,self-corrosio n,and other side reactions have seriously hindered the development and commercialization of *** increasing number of researchers are focusing on the stability of ZMAs,so assessing the effectiveness of existing research strategies is critical to the development of *** review aims to provide a comprehensive overview of the fundamentals and challenges of *** rch strategies for interfacial modification of ZMAs are systematically *** features of artificial interfacial coating and in-situ interfacial coating of ZMAs are compared and discussed in detail,as well as the effect of modified interfacial ZMA on the full-battery ***,perspectives are provided on the problems and challenges of *** review is expected to offer a constructive reference for the further development and commercialization of AZMBs.

关键词： Aqueous zinc metal batteries Zinc metal anode Interfacial modification Artificial interfacial coating In-situ interfacial coating

松辽盆地深层火山岩储层包裹体及天然气成藏期研究

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天然气地球科学 2003年第6期14卷 436-442页

作者：冯子辉任延广王成李景坤王雪关秋华大庆油田有限责任公司勘探开发研究院

火山岩气藏是松辽盆地深层天然气勘探的重要领域。应用显微热台和激光拉曼光谱技术,研究了徐家围子断陷火山岩气藏储层原生包裹体和次生包裹体的流体组成和均一化温度特征后发现:该储层原生和次生包裹体的流体性质有明显差异;次生包裹... 详细信息

火山岩气藏是松辽盆地深层天然气勘探的重要领域。应用显微热台和激光拉曼光谱技术,研究了徐家围子断陷火山岩气藏储层原生包裹体和次生包裹体的流体组成和均一化温度特征后发现:该储层原生和次生包裹体的流体性质有明显差异;次生包裹体组成与目前在储层中见到的天然气相似,其均一化温度可以反映天然气的成藏期。利用次生包裹体形成温度并结合储层的热演化史分析确定的单井成藏期表明:徐家围子断陷火石岭组天然气成藏期为114～68Ma,主要成藏期为90～70Ma,成藏时间一般大于10Ma,从断陷南部向北部,天然气的成藏期呈现逐渐变新的趋势;营城组天然气的成藏期为100～65Ma,主要成藏期为100～80Ma,成藏时间一般小于10Ma,从断陷北部向南部,天然气的成藏期呈现逐渐变新的趋势。徐家围子断陷天然气成藏期的变化主要与烃源岩展布的分割性和埋藏史的差异性有关;该气藏横向分布受源岩区控制。

关键词：火山岩储层包裹体天然气成藏期均一化温度

Quantifying quantum entanglement via machine learning models

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Communications in Theoretical Physics 2024年第7期76卷 52-56页

作者： changchun Feng Lin Chen LMIB(Beihang university) Ministry of EducationBeijing 100191China School of Mathematical Sciences Beihang UniversityBeijing 100191China International Research Institute for Multidisciplinary Science Beihang UniversityBeijing 00191China

Quantifying entanglement measures for quantum states with unknown density matrices is a challenging *** learning offers a new perspective to address this *** training machine learning models using experimentally measurable data,we can predict the target entanglement *** this study,we compare various machine learning models and find that the linear regression and stack models perform better than *** investigate the model's impact on quantum states across different dimensions and find that higher-dimensional quantum states yield better ***,we investigate which measurable data has better predictive power for target entanglement *** correlation analysis and principal component analysis,we demonstrate that quantum moments exhibit a stronger correlation with coherent information among these data features.

关键词： quantum information entanglement predict machine learning coherence

Finite-time composite learning control for nonlinear teleoperation systems under networked time-varying delays

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Science china(Information Sciences) 2024年第6期67卷 279-296页

作者： Yana YANG Huixin JIANG changchun HUA Junpeng LI Institute of Electrical Engineering Yanshan University

The robust finite-time synchronization control problem is investigated for master-slave networked nonlinear telerobotics systems(NNTSs) in this article. Although there have been some research achievements on finite-time control for the NNTSs, these studies are based on the strong assumptions of communication time delays or can only achieve finite-time bounded convergence even when the external forces are *** and in view of the importance of these issues, a novel robust composite learning adaptive control scheme rendering the finite-time master-slave synchronization is proposed in this paper. In particular, the influence of time delays on finite-time convergence of the system is analyzed by employing the multi-dimension finite-time small-gain framework. Meanwhile, in order to achieve accurate and fast estimation of uncertain parameters of the system, both the online historical and the instantaneous data of the estimation data are explored to derive the new parameter adaptive law under a more realizable interval-excitation(IE) ***, the convergence of the position/force synchronization errors and the adaptive parameter estimation errors is obtained in finite time, and enhanced robustness of the closed-loop system will also be ***, the superior performance of the proposed control algorithms is validated by numerical simulations and hardware experiments.

关键词： networked teleoperation systems finite-time control exact parameter estimation small-gain theorem unknown communication delays

Automatic Road Tunnel Crack Inspection Based on Crack Area Sensing and Multiscale Semantic Segmentation

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Computers, Materials & Continua 2024年第4期79卷 1679-1703页

作者： Dingping Chen Zhiheng Zhu Jinyang Fu jilin He College of Mechanical and Electrical Engineering Central South UniversityChangsha410083China Department of Geotechnical Guangdong Hualu Transportation Technology Company LimitedGuangzhou510000China National Engineering Research Center of High-Speed Railway Construction Technology Changsha410075China

The detection of crack defects on the walls of road tunnels is a crucial step in the process of ensuring travel safetyand performing routine tunnel maintenance. The automatic and accurate detection of cracks on the surface of roadtunnels is the key to improving the maintenance efficiency of road tunnels. Machine vision technology combinedwith a deep neural network model is an effective means to realize the localization and identification of crackdefects on the surface of road *** propose a complete set of automatic inspection methods for identifyingcracks on the walls of road tunnels as a solution to the problem of difficulty in identifying cracks during manualmaintenance. First, a set of equipment applied to the real-time acquisition of high-definition images of walls inroad tunnels is designed. Images of walls in road tunnels are acquired based on the designed equipment, whereimages containing crack defects are manually identified and selected. Subsequently, the training and validationsets used to construct the crack inspection model are obtained based on the acquired images, whereas the regionscontaining cracks and the pixels of the cracks are finely labeled. After that, a crack area sensing module is designedbased on the proposed you only look once version 7 model combined with coordinate attention mechanism (CAYOLOV7) network to locate the crack regions in the road tunnel surface images. Only subimages containingcracks are acquired and sent to the multiscale semantic segmentation module for extraction of the pixels to whichthe cracks belong based on the DeepLab V3+ network. The precision and recall of the crack region localizationon the surface of a road tunnel based on our proposed method are 82.4% and 93.8%, respectively. Moreover, themean intersection over union (MIoU) and pixel accuracy (PA) values for achieving pixel-level detection accuracyare 76.84% and 78.2.%, respectively. The experimental results on the dataset show that our proposed two-staged

关键词： Road tunnel crack inspection crack area sensing multiscale semantic segmentation CA-YOLO V7 DeepLab V3+

A Novel Sensing Imaging Equipment Under Extremely Dim Light for Blast Furnace Burden Surface:Starlight High-Temperature Industrial Endoscope

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 893-906页

作者： Zhipeng Chen Xinyi Wang Weihua Gui jilin Zhu Chunhua Yang Zhaohui Jiang The authors are with the School of Automation Central South UniversityChangsha 410083China

Blast furnace(BF)burden surface contains the most abundant,intuitive and credible smelting information and acquiring high-definition and high-brightness optical images of which is essential to realize precise material charging control,optimize gas flow distribution and improve ironmaking *** has been challengeable to obtain high-quality optical burden surface images under high-temperature,high-dust,and extremelydim(less than 0.001 Lux)*** on a novel endoscopic sensing detection idea,a reverse telephoto structure starlight imaging system with large field of view and large aperture is *** with a water-air dual cooling intelligent self-maintenance protection device and the imaging system,a starlight high-temperature industrial endoscope is developed to obtain clear optical burden surface images stably under the harsh *** on an endoscope imaging area model,a material flow trajectory model and a gas-dust coupling distribution model,an optimal installation position and posture configuration method for the endoscope is proposed,which maximizes the effective imaging area and ensures large-area,safe and stable imaging of the device in a confined *** experiments and applications indicate that the proposed method obtains clear and reliable large-area optical burden surface images and reveals new BF conditions,providing key data support for green iron smelting.

关键词： Blast furnace(BF) burden surface extremely dim light industrial endoscope sensing imaging starlight

Preparation of α-High Strength Gypsum from Flue Gas Desulfurization Gypsum Pretreated by Hydrothermal-aging Method

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Journal of Wuhan university of Technology(Materials Science) 2024年第1期39卷 75-81页

作者：苏一鑫 GAO Lili 陈学青 LI Zhishui 李雲 CAO jilin Engineering Research Center of Seawater Utilization Technology of Ministry of Education School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Heze Center for Disease Control and Prevention Heze 274010China Tianjin Bohua Yongli Chemical Industry Co. Ltd.Tianjin 300452China

The synthesis of α-calcium sulfate hemihydrate (α-CSH) from flue gas desulfurization (FGD)gypsum is a good way to realize the comprehensive utilization of FGD gypsum. To obtainα-CSH with the satisfactory performances, a facile hydrothermal-aging pretreatment process for FGD gypsum raw materials was proposed, where FGD gypsum was firstly hydrothermally converted to α-CSH whiskers, and α-CSH whiskers were further hydrated to synthesize CaSO4·2.2. (CSD) by aging under the regulation of N,N'-methylenebisacrylamide (MBA). The effects of aging time, MBA addition, aging temperature, and pH on the morphology of the synthesized CSD were investigated. The synthesized CSD crystals exhibit highly uniform prismatic morphology with the length of ca 100μm and the whiteness of 91.56%. The regulation mechanism of MBA was also illustrated. The synthesized CSD crystals with prismatic morphology were further used as raw materials to synthesize the short columnar α-CSH. The absolute dry compressive strength of paste prepared from the short columnar α-CSH is 40.85 MPa, which reaches α40 strength grade.

关键词： flue gas desulphurization gypsum α-calcium sulfate hemihydrate hydrothermal-aging method N,N'-methylenebisacrylamide prismatic CSD

Roles of Salicylic Acid-responsive Cis-acting Elements and W-boxes in Salicylic Acid Induction of VCH3 Promoter in Transgenic Tobaccos

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Acta Biochimica et Biophysica Sinica 2006年第1期38卷 46-52页

作者： Hai-Yan LI~(1,2.,Wei WEI~(2.),and Yu LI~(1*) ~1 Institute of Mycology,jilin Agricultural university,{2. 130118,china ~2.College of Biotechnology,jilin Agricultural university,{2. 130118,china Institute of Mycology Jilin Agricultural University Changchun 130118 China College of Biotechnology Jilin Agricultural University Changchun 130118 China

A salicylic acid (SA)-inducible VCH3 promoter was recently identified from grapevine (Vitisarnurensis) that contains two inverse SA-responsive cis-acting elements and four *** furtherdemonstrate the roles of these elements,four fragments with lengths from-1187,-892.-589,-2.6 to+7 bp were fused with the β-glucuronidase (GUS) reporter géne and transferred to Nicotiana tobacum,together with another four VCH3 promoter fragments with mutation in the two inverse *** functions,of each promoter fragment were-examined by analysis of GUS activity in thetransgenic tobacco root treated with *** GUS activity was shown in the roots of transgenictobaccos with the VCH3 (-1187)-GUS construct containing two SA-responsive cis-acting elements andfour ***,GUS activity directed by the VCH3 (-892.-GUS construct,containing one SA cis-acting element and four W-boxes,was reduced by up to 35% compared with that in tobaccos transformedwith the VCH3 (-1187)-GUS construct,indicating that the SA cis-acting element plays an important role inSA induction of the VCH3 *** the m2.CH3 (-1187)-GUS nor the mVCH3 (-892.-GUSconstruct,with mutation on the SA-responsive elements,abolished the expression of GUS activity,demon-strating that the W-boxes in the VCH3 promoter are also involved in SA *** arialysis ofGUS activity directed by each of the eight VCH3 promoter fragments showed that GUS was expressedspecifically in vascular *** was concluded that both the SA-responsive cis-acting elements and the W-boxes are important for the SA induction of the VCH3 *** promoter might have a potential usein plant genetic engineering.

关键词： VCH3 promoter salicylic acid(SA)-responsive cis-acting element W-box site-directed mutagenesis SA induction transgenic tobacco