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Identification of rural courtyards’utilization status using deep learning and machine learning methods on unmanned aerial vehicle images in north China

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Building Simulation 2024年第5期17卷 799-818页

作者： Maojun Wang wenyu xu Guangzhong Cao Tao Liu College of Resource Environment and Tourism Capital Normal UniversityBeijing 100048China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

The issue of unoccupied or abandoned homesteads(courtyards)in China emerges given the increasing aging population,rapid urbanization and massive rural-urban *** the aspect of rural vitalization,land-use planning,and policy making,determining the number of unoccupied courtyards is *** and questionnaire-based surveys were currently the main approaches,but these traditional methods were often expensive and laborious.A new workflow is explored using deep learning and machine learning algorithms on unmanned aerial vehicle(UAV)***,features of the built environment were extracted using deep learning to evaluate the courtyard management,including extracting complete or collapsed farmhouses by Alexnet,detecting solar water heaters by YOLOv5s,calculating green looking ratio(GLR)by *** precisions exceeded 98%.Then,seven machine learning algorithms(Adaboost,binomial logistic regression,neural network,random forest,support vector machine,decision trees,and XGBoost algorithms)were applied to identify the rural courtyards’utilization *** Adaboost algorithm showed the best performance with the comprehensive consideration of most metrics(Accuracy:0.933,Precision:0.932,Recall:0.984,F1-score:0.957).Results showed that identifying the courtyards’utilization statuses based on the courtyard built environment is *** is transferable and cost-effective for large-scale village surveys,and may contribute to the intensive and sustainable approach to rural land use.

关键词： unoccupied homesteads courtyard built environment inner courtyard management GLR solar water heaters machine learning algorithms

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Effects of processing parameters on fabrication defects,microstructure and mechanical properties of additive manufactured Mg–Nd–Zn–Zr alloy by selective laser melting process

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Journal of Magnesium and Alloys 2024年第6期12卷 2249-2266页

作者： wenyu xu Penghuai Fu Nanqing Wang Lei Yang Liming Peng Juan Chen Wenjiang Ding National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite School of Materials Science and EngineeringShanghai Jiao Tong University800 Dongchuan RoadShanghai 200240China Shanghai Light Alloy Net Forming National Engineering Research Center Co. LtdShanghai 201615China

Mg–3Nd–0.2Zn–0.4Zr(NZ30K,wt.%)alloy is a new kind of high-performance metallic *** combination of the NZ30K Magnesium(Mg)alloy and selective laser melting(SLM)process seems to be an ideal solution to produce porous Mg degradable ***,the microstructure evolution and mechanical properties of the SLMed NZ30K Mg alloy were not yet studied ***,the fabrication defects,microstructure,and mechanical properties of the SLMed NZ30K alloy under different processing parameters were *** results show that there are two types of fabrication defects in the SLMed NZ30K alloy,gas pores and unfused *** the increase of the laser energy density,the porosity sharply decreases to the minimum first and then slightly *** minimum porosity is 0.49±0.18%.While the microstructure varies from the large grains with lamellar structure inside under low laser energy density,to the large grains with lamellar structure inside&the equiaxed grains&the columnar grains under middle laser energy density,and further to the fine equiaxed grains&the columnar grains under high laser energy *** lamellar structure in the large grain is a newly observed microstructure for the NZ30K Mg *** laser energy density leads to finer grains,which enhance all the yield strength(YS),ultimate tensile strength(UTS)and elongation,and the best comprehensive mechanical properties obtained are YS of 266±2.1 MPa,UTS of 296±5.2 MPa,with an elongation of 4.9±0.68%.The SLMed NZ30K Mg alloy with a bimodal-grained structure consisting of fine equiaxed grains and coarser columnar grains has better elongation and a yield drop phenomenon.

关键词： Selective laser melting Mg alloy Processing parameter Lamellar structure Bimodal-grained structure

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青岛市海洋文化资源挖掘与产业化分析

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中国海洋经济 2024年第1期 42-55,170,171页

作者：徐文玉山东社会科学院

青岛市海洋文化资源丰富,是“青岛风貌”和“青岛精神”的书写,也是青岛海洋文明的重要组成部分。随着对海洋文化资源的挖掘,青岛海洋文化资源的产业化发展取得一定成就,蓝色软实力不断提升,但海洋文化资源挖掘力度不足、海洋文化产业... 详细信息

青岛市海洋文化资源丰富,是“青岛风貌”和“青岛精神”的书写,也是青岛海洋文明的重要组成部分。随着对海洋文化资源的挖掘,青岛海洋文化资源的产业化发展取得一定成就,蓝色软实力不断提升,但海洋文化资源挖掘力度不足、海洋文化产业化发展规模偏小、产业化结构不合理、创新乏力等问题依然制约着青岛海洋文化的高质量发展。因此,需要把握青岛海洋文化资源要素条件,实施海洋文化挖掘工程,创新海洋文化发展模式,大力发展乡村渔村海洋文化,为打造现代产业先行城市和引领型现代海洋城市发挥应有作用。

关键词：海洋文化海洋文化产业现代海洋城市海洋文明青岛

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碳强度下现有营运船舶减排对策分析

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上海船舶运输科学研究所学报 2024年第4期47卷 39-43,49页

作者：徐文宇王楠南通中远海运川崎船舶工程有限公司江苏南通226005

在航运业降碳背景下,针对营运船舶碳排放法规的要求,建立营运船舶碳排放评估数学模型,并基于某集装箱船的运营数据对现有减排措施的碳强度和经济性进行分析。结果表明:短期内通过航速管理并辅以有效的减排技术,能满足未来约10 a的碳强... 详细信息

在航运业降碳背景下,针对营运船舶碳排放法规的要求,建立营运船舶碳排放评估数学模型,并基于某集装箱船的运营数据对现有减排措施的碳强度和经济性进行分析。结果表明:短期内通过航速管理并辅以有效的减排技术,能满足未来约10 a的碳强度评级要求,而更大幅度地降低航速会影响船舶运营成本;中长期内可通过采用混合生物燃油和加强船队管理等方式降低船舶营运碳排放,使现有船舶在营运周期内能满足碳强度评级最低要求。

关键词：碳强度营运船减排措施营运周期经济性

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Plasma levels of luteinizing hormone and prolactin in relation to double brooding in Great Tit(Parus major)

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Avian Research 2022年第1期13卷 102-107页

作者： xudong Li wenyu xu Jiangping Yu Wutong Zhang Haitao Wang Jilin Engineering Laboratory for Avian Ecology and Conservation Genetics School of Life SciencesNortheast Normal UniversityChangchun130024China Jilin Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal UniversityChangchun130024China

The reproductive behaviors of birds are mainly controlled by the hypothalamus-pituitary-gonad *** studies have shown that reproductive hormones are tightly linked to the breeding ***,only a few studies have examined the temporal trend of hormone levels among different reproductive stages in multiple brooded *** investigated the changes in plasma luteinizing hormone(LH)and prolactin(PRL)concentrations during different reproductive stages of the facultative double-brooded Great Tit(Parus major).We found that the concentrations of LH and PRL in females were significantly higher than those in *** had significantly higher LH and lower PRL concentrations in the pre-breeding period than in the first/second brooding periods,and there were no significant changes between the first and second brooding *** concentrations of LH and PRL in males had no significant difference between the pre-breeding period and the first brooding periods,while LH and PRL concentrations in the second brooding period were significantly higher than those in the first brooding *** conclude that there are sex-based differences between LH and PRL at different stages of *** changes in LH and PRL in both males and females should be related to their physiological *** for males,individuals with higher levels of LH and PRL are more likely to maintain second clutches.

关键词： Birds Great Tit Luteinizing hormone Prolactin Seasonal breeding

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Tailoring interlayer spacing in MXene cathodes to boost the desalination performance of hybrid capacitive deionization systems

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Nano Research 2023年第5期16卷 6039-6047页

作者： Bei Li Kang Sun wenyu xu Xiaojing Liu Ao Wang Steven Boles Bin xu Haibo Hu Dongrui Yao Jiangsu Engineering Research Center of Aquatic Plant Resources and Water Environment Remediation Institute of BotanyJiangsu Province and Chinese Academy of SciencesNanjing 210014China Institute of Chemical Industry of Forest Products Chinese Academy of ForestryNanjing 210042China School of Materials Science and Engineering Anhui UniversityHefei 230601China Department of Energy and Process Engineering Norwegian University of Science and TechnologyTrondheimNorway Nanjing Institute of Environmental Sciences Ministry of Ecology and Environment of the People's Republic of ChinaNanjing 210042China

Capacitive deionization(CDI)is a promising technology to satisfy the global need for fresh water,since it can be both economical and *** two-dimensional transition metal carbides/nitrides(MXenes)exhibit great characteristics for use as CDI electrode materials,their tightly spaced layered structure renders intercalation *** this study,the interlayer distance of MXenes is precisely modulated by inserting different quantity of one-dimensional bacterial fibers(BC),forming freestanding MXene/BC composite *** the studied samples,MXene/BC-33%electrode with the interlayer spacing of 15.2Åcan achieve an optimized tradeoff among various desalination performance metrics and *** salt adsorption capacity(SAC),the average salt adsorption rate(ASAR),the energy normalized adsorbed salt(ENAS),and the thermodynamic energy efficiency(TEE)of the MXene/BC-33%electrode are improved by 24%,46%,13%,and 66%respectively compared with those of pure MXene *** the insertion of BC improves the ion diffusion pathways and facilitates the intercalation kinetics,the desalination performance decreases when the insertion amount of BC exceeds 40%.This is attributed to the overlarge resistance of the composite and the resulting increased energy *** study reveals the desalination performance tradeoffs of MXene-based electrodes with different interlayer distances and also sheds light on the fundamental ion storage mechanisms of intercalation materials in a CDI desalination system.

关键词： capacitive deionization MXene intercalation materials hybrid capacitive deionization cation intercalation

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郑州市水利遗产时空分布特征及影响因素研究

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绿色科技 2024年第11期26卷 186-191页

作者：徐文煜卢玫珺宋海静华北水利水电大学建筑学院河南郑州450045

郑州市是历史文化名城,其深厚的历史积淀孕育了丰富且独特的水文化,留下了丰富的遗产,开展郑州市水利遗产研究,有助于推动其开发利用和保护传承。选取郑州市水利遗产,借助空间信息技术,构建了郑州市水利遗产空间数据库,完善形成年代、... 详细信息

郑州市是历史文化名城,其深厚的历史积淀孕育了丰富且独特的水文化,留下了丰富的遗产,开展郑州市水利遗产研究,有助于推动其开发利用和保护传承。选取郑州市水利遗产,借助空间信息技术,构建了郑州市水利遗产空间数据库,完善形成年代、类型特征等数据,结合ArcGIS分析工具对其空间数据进行了处理分析。结果表明:郑州市水利遗产在时间上大致呈建造时间越久远,遗存数量越稀少的趋势。在空间上总体呈明显的集聚态,在类型上供排水工程类聚集在无主要河道流经的刘和镇、崔庙镇一带;水利遗址类聚集在新郑市南部地区;其余类型遗产主要集中在伊洛河、索须河周边范围,向外扩展,数量随距离增加而减少。其形成与经济、贸易、政治、文化等多种因素相关。

关键词：水利遗产水文化遗产时空分布特征遗产保护

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V_(2)CT_(X) MXene Sphere for Aqueous Ion Storage

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Energy Material Advances 2023年第1期4卷 512-521页

作者： Xinliang Li Mian Li wenyu xu Zhaodong Huang Guojin Liang Qi Yang Qing Huang Chunyi Zhi Key Laboratory of Material Physics Ministry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China Department of Materials Science and Engineering City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong 999077China Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Industrial TechnologyChinese Academy of SciencesNingboZhejiang 315201China Centre for Functional Photonics City University of Hong KongKowloonHong Kong 999077China

Despite the remarkable ion-hosting capability of MXenes,their electrochemical performance is restricted to the ion shuttle barrier stemming from the capacious surface and the sluggish chemical activity of intrinsic transition metal ***,we construct a vertically aligned array of V_(2)CT_(X) flakes utilizing a carbon sphere template(V_(2)CT_(X)@CS),with the interlayer galleries outward facing the external electrolyte,to shorten the diffusion length and mitigate the ion shuttle ***,we leverage the high sensitivity of V_(2)CT_(X) flakes to the water-oxygen environment,fully activating the masked active sites of transition metal layers in an aqueous environment via continuous electrochemical *** V_(2)CT_(X)@CS/Zn battery delivers a novel capacity enhancement over 42,000 cycles at 10 A g^(−1).After activation,the capacity reaches up to 409 mAh g^(−1) V_(2)CT_(X) at 0.5 A g^(−1) and remains at 122 mAh g^(−1) V_(2)CT_(X) at 18 A g^(−1).With a 0.95-V voltage plateau,the energy density of 330.4 Wh kg^(−1) V_(2)CT_(X) surpasses previous records of aqueous MXene electrodes.

关键词： utilizing battery template

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Experimental Study on Mixed-Mode(Ⅰ–Ⅱ)Fracture Toughness of Freshwater Ice

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Acta Mechanica Solida Sinica 2024年第2期37卷 252-264页

作者： Yaozhong xu Mao Zhou Xian Yi Wen Hua Jiuzhou Huang wenyu Zhang Shiming Dong Key Laboratory of Deep Underground Science and Engineering Ministry of EducationCollege of Architecture and EnvironmentSichuan UniversityChengdu610065China Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan Province Sichuan UniversityChengdu610065China China Aerodynamics Research and Development Center/Low Speed Aerodynamics Research Institute Mianyang621000China College of Mechanical and Electrical Engineering Xichang UniversityXichang615000China

In recent years,the issue of aircraft icing has gained widespread *** breaking and detachment of dynamic ice can pose a threat to flight ***,the shedding and fracture mechanisms of dynamic ice are unclear and cannot meet the engineering needs of ice-shedding hazard ***,studying the fracture toughness of ice bodies has extremely important practical *** address this issue,this article uses a centrally cracked Brazilian disk(CCBD)specimen to measure the pure modeⅠtoughness and pure modeⅡfracture toughness of freshwater ice at different loading *** mixed-mode(Ⅰ–Ⅱ)fracture characteristics of ice are discussed,and the experimental results are compared and analyzed with the theoretical values of the generalized maximum tangential stress(GMTS)criterion considering the influence of *** results indicated that as the loading rate increases,the pure modeⅠtoughness and pure modeⅡfracture toughness of freshwater ice decrease,and the fracture toughness of freshwater ice is more sensitive to the loading rate.Ⅰn terms of fracture criteria,the theoretical value of the ratio of pure modeⅡfracture toughness to pure modeⅠfracture toughness based on the GMTS criterion is in good agreement with the experimental value,while the theoretical value based on the maximum tangential stress(MTS)criterion deviates significantly from the experimental value,indicating that the GMTS criterion considering the influence of T-stress can better predict the experimental results.

关键词： Freshwater ice Fracture criteria Centrally cracked Brazilian disk(CCBD) Mixed-mode(Ⅰ-Ⅱ) Loading rate

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Pixelated non-volatile programmable photonic integrated circuits with 20-level intermediate states

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International Journal of Extreme Manufacturing 2024年第3期6卷 477-487页

作者： wenyu Chen Shiyuan Liu Jinlong Zhu State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China Optics Valley Laboratory WuhanHubei 430074People’s Republic of China

Multi-level programmable photonic integrated circuits(PICs)and optical metasurfaces have gained widespread attention in many fields,such as neuromorphic photonics,opticalcommunications,and quantum *** this paper,we propose pixelated programmable Si_(3)N_(4)PICs with record-high 20-level intermediate states at 785 nm *** flexibility in phase or amplitude modulation is achieved by a programmable Sb_(2)S_(3)matrix,the footprint of whose elements can be as small as 1.2μm,limited only by the optical diffraction limit of anin-house developed pulsed laser writing *** believe our work lays the foundation for laser-writing ultra-high-level(20 levels and even more)programmable photonic systems and metasurfaces based on phase change materials,which could catalyze diverse applications such as programmable neuromorphic photonics,biosensing,optical computing,photonic quantum computing,and reconfigurable metasurfaces.

关键词： programmable photonic integrated circuits phase change materials multi-level intermediate states metasurfaces

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