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Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean engineering 2024年第2期38卷 313-325页

作者： DONG Wen-bo ZHOU Li DING Shi-feng WANG Ai-ming CAI Jin-yan school of Naval architecture and Ocean engineering Jiangsu University of Science and TechnologyZhenjiang 212003China school of Naval architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of *** the Arctic,merchant ships with low ice class often navigate in channels opened up by *** in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large *** ship may get stuck if steered into ice fields off the *** this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable *** this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point *** first stage employs the image segmentation method to extract channel *** the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression *** training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel *** evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

The Role of the Spatial Network in Urban Disaster Risk Variations:Reimagining the Notion of Spatial Vulnerability at the Urban Scale

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International Journal of Disaster Risk Science 2024年第3期15卷 303-316页

作者： Monia Del Pinto Ksenia Chmutina Falli Palaiologou Lee Bosher school of architecture Building and Civil Engineering Loughborough University school of Business University of Leicester

The notion of “spatial vulnerability” is present in most disaster studies with a strong geographical connotation and accordingly is adopted at all scales, including the urban. While enabling mapping and visualizing risk patterns at macroscales, this geocentric foundation fails to capture disaster risk dynamics associated with the urban spatial network—an element that plays a significant role in the everyday and emergency functioning of cities, enabling users' movement and interaction. Yet,urban vulnerability assessment overlooks this aspect and thus leaves urban disaster risk mechanisms partially *** study investigated the role of the network of urban public open spaces(UPOS) in the creation and progression of urban disaster risk in earthquake-prone settlements. Through a multimethod approach that integrates quantitative and qualitative methods and explores spatial configuration, planning policies, and practices of use of UPOS in everyday and emergency scenarios, our study demonstrated that UPOS configuration plays an active role in urban disaster risk. Urban public open spaces impact risk by influencing the exposure of pedestrians and their capacity for self-protection. The study further reconceptualized spatial vulnerability at the urban scale, as the fraction of vulnerability associated to the spatial network, highlighting the interplay of planning policies and spatial practices in its production and progression. Our findings make the notion of spatial vulnerability less ambiguous at the urban scale, by viewing the variable as an imbalance in capacities and exposure that generates spatially unsafe conditions. This refined conceptualization of spatial vulnerability becomes a lens for a more granular approach to urban disaster risk reduction and city planning by identifying and integrating sociospatial considerations.

关键词： Central Italy Earthquakes Pedestrian evacuation Space syntax Spatial vulnerability Urban disaster risk

Re-delocalization of localized d-electrons in VO2（R）-VS4 hetero-structure enables high performance of rechargeable Mg-ion batteries

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Journal of Magnesium and Alloys 2024年第5期12卷 1830-1840页

作者： Lijiao Zhou Chao Shen Xueyang Hou Zhao Fang Ting Jin Keyu Xie school of Materials Science and engineering Northwestern Polytechnical University school of Metallurgical engineering Xi'an University of Architecture and Technology

Rechargeable Mg-ion batteries（MIBs） have attracted much more attentions by virtue of the high capacity from the two electrons ***, the reversible Mg2+diffusion in cathode materials is restricted by the strong interactions between the high-polarized bivalent Mg2+ions and anionic lattice. Herein, we design and propose a hetero-structural VO2（R）-VS4cathode, in which the re-delocalized d-electrons can effectively shield the polarity of Mg2+ions. Theoretically, the electrons should spontaneously transfer from VS4to VO2（R） through the interfaces of hetero-structure due to the lower work function value of VS4. Furthermore, the internal electrons transfer lead to the electronic injection into VO2（R） from VS4and the partially broken V-V dimers, indicating the presence of lone pair electrons and charge re-delocalization. Benefiting from the shield effect of re-delocalized electrons, and the weakened attraction between cations and O/S anions enables more S2--S22-redox groups to participate the electrochemical reactions and compensate the double charge of Mg2+ions. Accordingly,VO2（R）-VS4hetero-structure exhibits a high specific capacity of 554 mA h g-1at 50 mA g-1. It is believed that the charge re-delocalization of cathode extremely boost the Mg2+ions migration for the high-capacity of MIBs.

关键词： Mg-ion batteries Cathode Charge delocalization Electronic structure Heterostructure

Study on the mechanism and reaction characteristics of metal-supported phosphogypsum as oxygen carrier in a chemical looping gasification application

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Journal of Environmental Sciences 2024年第4期138卷 428-438页

作者： Jing Yang Yujie Ren Shuoyu Chen Jinsuo Lu school of Environmental and Municipal engineering Xi’an University of Architecture and TechnologyXi’an 710055China

This study aimed to explore the chemical looping gasification(CLG)reaction characteristics of the metal-supported composite phosphogypsum(PG)oxygen carriers(OCs)and the thermodynamic *** FactSage 7.1 thermodynamic simulation was used to explore the oxygen release and H_(2)S removal *** experimental results showed that the syngas yield of CLG with PG-CuFe_(2)O_(4)was more than that with PG-Fe_(2)O_(3)20/CuO40 or PG-Fe_(2)O_(3)30/CuO30 OC at 1023 K when the water vapor content was ***,the maximum syngas yield of the CO selectivity was 70.3% and of the CO_(2)selectivity was 23.8%.The H_(2)/CO value was 0.78,and the highest carbon conversion efficiency was 91.9% in PG-CuFe_(2)O_(4)at the gasification temperature of 1073 *** metal-supported PG composite oxygen carrier was proved not only as an oxygen carrier to participate in the preparation of syngas but also as a catalyst to catalyze coal gasification ***,both the experimental results and FactSage 7.1 thermodynamic analysis revealed that the trapping mechanism of H_(2)S by composite OCs was as follows:CuO first lost lattice oxygen as an oxygen carrier to generate Cu_(2)O,which,in turn,reacted with H_(2)S to generate Cu_(2)*** study provided efficient guidance and reference for OC design in CLG.

关键词： Metal-supported composite phosphogypsum Reaction characteristics Thermodynamic mechanism Chemical looping gasification

Efficient Removal of Phosphate from Aqueous Solutions Using Corundum-hollow-spheres Supported Caclined Hydrotalcite Porous Thin Films

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 44-49页

作者：刘云才 ZHU Chen school of architecture and Materials engineering Hubei Second Normal UniversityWuhan 430205China

Phosphate was removed from aqueous environment by corundum-hollow-spheres supported caclined hydrotalcite (cHT) thin films. Mg-Al-CO3 hydrotalcite (HT) thin films were deposited on corundumhollow-sphere substrates by hydrothermal homogeneous precipitation at 120℃for 30-240 min and cHT thin films were obtained by annealing of the HT thin films at 500℃for 180 min. Their crystal phase, morphology and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).The results show that homogeneous, well-crystallized and hierarchical flower-like thin films were deposited firmly on the surface of the corundum. The mechanism of nucleation and growth of the HT thin films was fitted well with the anion coordination polyhedron growth unit model. To determine the absorption of phosphate by this adsorbent, different bed depth (10-30 cm) and flow rate (1.0-3.0 m L/min) were examined by column experiments. The highest removal efficiency of phosphate amounted to 98.5%under optimum condition (pH=7.2). The adsorption capacity increased as the bed depth increased and decreased as the flow rate increased.

关键词： adsorption phosphate hydrotalcite corundum-hollow-sphere hydrothermal homogeneous precipitation thermal anneal

A Comprehensive Study on the Consequences of Gap-Graded Sands Considering the Loss of Fine Particles

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Journal of Earth Science 2024年第2期35卷 597-612页

作者： Weiping Liu Yu Gan Yunwei Cui Faming Huang Lina Hu school of Civil engineering and architecture Nanchang UniversityNanchang330031China

Water and sand leakage disasters are likely to occur during construction in water-rich sand layer areas,resulting in ground *** stress-strain action characteristics of discontinuous graded sand under different internal erosion degrees,and the evolution mechanism of water and sand leakage disasters caused by the internal erosion need to be further ***,this paper takes the discontinuous graded sand in a water rich sand layer area in Nanchang City of China as the research *** the influence of different fine particle losses(0,10%,20%and 30%)under the internal erosion of sand,the salt solution method is used to realize the specified loss of fine particles in the internal *** stress-strain behavior after the loss of fine particles due to internal erosion is studied by triaxial shear ***,the physical model test and PFC-CFD method are both used to study the evolution rules of water and sand leakage disaster considered the influence of internal erosion *** show that:(1)under the same confining pressure,the peak failure strength of sand samples decreases along with the increase of fine particle loss.(2)In the water and sand leakage test of saturated sand,a natural filter channel is formed above the observed soil *** greater the loss of fine particles,the steeper and wider the collapse settlement area.(3)The relationship between the cumulative amount of water and sand leakage and time is *** total mass loss of sand increases along with the increase of internal erosion degree.(4)After the soil arch is formed around the damaged opening,the sand continues to converge above the soil arch under the action of water flow,resulting in the dense convergence of contact force chains.

关键词： sandy soil internal erosion stress and strain water and sand leakage PFC3D engineering geology

Graph Convolutional Networks Embedding Textual Structure Information for Relation Extraction

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Computers, Materials & Continua 2024年第5期79卷 3299-3314页

作者： Chuyuan Wei Jinzhe Li Zhiyuan Wang Shanshan Wan Maozu Guo school of Electrical and Information engineering Beijing University of Civil Engineering and ArchitectureBeijing102616China

Deep neural network-based relational extraction research has made significant progress in recent years,andit provides data support for many natural language processing downstream tasks such as building knowledgegraph,sentiment analysis and question-answering ***,previous studies ignored much unusedstructural information in sentences that could enhance the performance of the relation extraction ***,most existing dependency-based models utilize self-attention to distinguish the importance of context,whichhardly deals withmultiple-structure *** efficiently leverage multiple structure information,this paperproposes a dynamic structure attention mechanism model based on textual structure information,which deeplyintegrates word embedding,named entity recognition labels,part of speech,dependency tree and dependency typeinto a graph convolutional ***,our model extracts text features of different structures from theinput *** Structure information Graph Convolutional Networks employs the dynamic structureattention mechanism to learn multi-structure attention,effectively distinguishing important contextual features invarious structural *** addition,multi-structure weights are carefully designed as amergingmechanismin the different structure attention to dynamically adjust the final *** paper combines these featuresand trains a graph convolutional network for relation *** experiment on supervised relation extractiondatasets including SemEval 2010 Task 8,TACRED,TACREV,and Re-TACED,the result significantly outperformsthe previous.

关键词： Relation extraction graph convolutional neural networks dependency tree dynamic structure attention

Pedestrian wind flow prediction using spatial-frequency generative adversarial network

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Building Simulation 2024年第2期17卷 319-334页

作者： Pengyue Wang Maozu Guo Yingeng Cao Shimeng Hao Xiaoping Zhou Lingling Zhao school of architecture and Urban Planning Beijing University of Civil Engineering and ArchitectureBeijing100044China Beijing Key Laboratory of Intelligent Processing for Building Big Data Beijing100044China school of Electrical and Information engineering Beijing University of Civil Engineering and ArchitectureBeijing100044China school of Computer Science and Technology Harbin Institute of TechnologyHarbin150001China

Pedestrian wind flow is a critical factor in designing livable residential environments under growing complex urban *** pedestrian wind flow during the early design stages is essential but currently suffers from inefficiencies in numerical *** learning,particularly generative adversarial networks(GAN),has been increasingly adopted as an alternative method to provide efficient prediction of pedestrian wind ***,existing GAN-based wind flow prediction schemes have limitations due to the lack of considering the spatial and frequency characteristics of wind flow *** study proposes a novel approach termed SFGAN,which embeds spatial and frequency characteristics to enhance pedestrian wind flow *** the spatial domain,Gaussian blur is employed to decompose wind flow into components containing wind speed and distinguished flow edges,which are used as the embedded spatial *** information of wind flow is obtained through discrete wavelet transformation and used as the embedded frequency *** spatial and frequency characteristics of wind flow are jointly utilized to enforce consistency between the predicted wind flow and ground truth during the training phase,thereby leading to enhanced *** results demonstrate that SFGAN clearly improves wind flow prediction,reducing Wind_MAE,Wind_RMSE and the Fréchet Inception Distance(FID)score by 5.35%,6.52%and 12.30%,compared to the previous best method,*** also analyze the effectiveness of incorporating the spatial and frequency characteristics of wind flow in predicting pedestrian wind *** reduces errors in predicting wind flow at large error intervals and performs well in wake regions and regions surrounding *** enhanced predictions provide a better understanding of performance variability,bringing insights at the early design stage to improve pedestrian wind *** proposed spatial-frequen

关键词： pedestrian wind flow prediction generative adversarial network Gaussian kernel wavelet transform objective function

2.5-dimension soil seismic response to oblique incident waves based on exact free-field solution

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Frontiers of Structural and Civil engineering 2024年第2期18卷 216-235页

作者： Yeongbin Yang Zeyang Zhou Xiaoli Wang Xiongfei Zhang Zhilu Wang school of Civil engineering Chongqing UniversityChongqing 400045China school of Civil engineering and architecture Chongqing University of Science and TechnologyChongqing 401331China

With the three dimensional(3D)oblique incident waves exactly determined for the free field,the soil seismic responses in both frequency and time domains are studied by the 2.5 dimension(2.5D)finite/infinite element ***,the free-field responses in frequency domain are solved exactly for 3D arbitrary incident P and SV waves,which requires no coordinate conversion or extra effort for SV waves with super-critical incident ***,the earthquake spectra are incorporated by the concept of equivalent seismic forces on the near-field boundary,based only on the displacements input derived for unit ground accelerations of each frequency using the 2.5D *** the asymmetric 2.5D finite/infinite element model adopted,the procedure for soil seismic analysis is *** solutions computed by the proposed method are verified against those of Wolf’s and de Barros and Luco’s and for inversely calculated ground *** interest is that abrupt variation in soil response occurs around the critical angle on the wave propagation plane for SV *** addition,the horizontal displacements attenuate with increasing horizontal incident angle,while the longitudinal ones increase inversely for 3D incident P and SV waves.

关键词： 3D oblique incident wave seismic response analysis 2.5D approach infinite element half-space