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基于Landsat和DMSP/OLS数据的“鬼城”指数监测研究——以安徽地区为例

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科技广场 2017年第6期 172-176页

作者：李傲张震苏浩然李益峰雷斌斌安徽理工大学测绘学院安徽淮南232000

随着城市化进程的加快,建成区迅速扩张。但是有限的人口和不合理的开发等因素造成了住房空置率高、入住率低的"鬼城"现象。在中国,由于数据获取的局限性和缺乏明确有效的评价标准,导致对人们对"鬼城"的了解相当有限。鉴于"鬼城"的事实,... 详细信息

随着城市化进程的加快,建成区迅速扩张。但是有限的人口和不合理的开发等因素造成了住房空置率高、入住率低的"鬼城"现象。在中国,由于数据获取的局限性和缺乏明确有效的评价标准,导致对人们对"鬼城"的了解相当有限。鉴于"鬼城"的事实,本研究借助于Landsat数据和DMSP/OLS数据建立"鬼城"快速评价方法体系,分析"鬼城"指数成因,为城乡合理规划提供实际参考和宏观依据。

关键词：城市化鬼城指数遥感城乡规划

铸轧AZ31镁合金板温轧过程微观组织及裂纹研究

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热加工工艺 2015年第21期44卷 39-42,46页

作者：梅瑞斌马西贝子杜永霞王雪崔然邹振巍苏浩然东北大学秦皇岛分校河北秦皇岛066004 东北大学材料与冶金学院辽宁沈阳110819 辽河油田公司钻采工艺研究院辽宁盘锦124010

研究了铸轧AZ31镁合金在125、175、225℃及单道次压下量10%和15%温轧工艺条件下板带金相组织、XRD和裂纹变化规律。结果表明低温轧制过程塑性变形主要是孪晶,变形带和剪切带,随变形量增加,粗大晶粒减小,条状孪晶增加;随温度升高,组织发... 详细信息

研究了铸轧AZ31镁合金在125、175、225℃及单道次压下量10%和15%温轧工艺条件下板带金相组织、XRD和裂纹变化规律。结果表明低温轧制过程塑性变形主要是孪晶,变形带和剪切带,随变形量增加,粗大晶粒减小,条状孪晶增加;随温度升高,组织发生了部分再结晶,单道次变形量增加,晶格畸变加剧,再结晶晶粒增多;温轧后形成了典型基面织构（0002）,且强度峰值随温度升高和压下量增加明显增强;尽管动态再结晶对裂纹愈合有明显积极作用,但过大压下量和过快温降导致变形不均匀性增加和裂纹无法完全消除。压下量10%,轧制温度200~250℃有利于铸轧AZ31镁合金后续温轧过程塑性改善和裂纹愈合。

关键词：铸轧AZ31镁合金温轧裂纹孪晶

Pre-warning information dissemination models of different media under emergencies

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Chinese Physics B 2020年第9期29卷 343-352页

作者： Anying Chen haoran Zhu Xiaoyong Ni Guofeng su Institute of Public Safety Research Tsinghua UniversityBeijing 100084China Beijing Key Laboratory of City Integrated Emergency Response Science Beijing 100084China

Pre-warning plays an important role in emergency handling, especially in urban areas with high population density like Beijing. Knowing the information dissemination mechanisms clearly could help us reduce losses and ensure the safety of human beings during emergencies. In this paper, we propose the models of pre-warning information dissemination via five classical media based on actual pre-warning issue processes, including television, radio, short message service (SMS), electronic screens, and online social networks. The population coverage ability and dissemination efficiency at different issue time of these five issue channels are analyzed by simulation methods, and their advantages and disadvantages are compared by radar graphs. Results show that SMS is the most appropriate way to issue long-term pre-warning for its large population coverage, but it is not suitable for issuing urgent warnings to large population because of the limitation of telecom company's issue ability. TV shows the best performance to combine the dissemination speed and range, and the performance of radio and electronic screens are not as satisfactory as the others. In addition, online social networks might become one of the most promising communication method for its potential in further diffusion. These models and results could help us make pre-warning issue plans and provide guidance for future construction of information diffusion systems, thus reducing injuries, deaths, and other losses under different emergencies.

关键词： information dissemination emergency pre-warning media

Visualization Techniques viaMLBS for Personnel Management in Major Events

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Computer Systems Science & Engineering 2023年第7期46卷 521-536页

作者： Yu su Lingjuan Hou Sinan Li Zhaochang Jiang haoran Peng The 54th Research Institute China Electronics Technology Group CorporationShijiazhuang050081China School of Management Tianjin Normal UniversityTianjin300387China Graduate School Sehan UniversityMokpo58613Korea Department of Electrical and Computer Engineering National Chiao Tung UniversityHsinchu City30010TaiwanChina

Mobile location-based services(MLBS)refer to services around geographic location *** terminals use wireless communication networks(or satellite positioning systems)to obtain users’geographic location coordinate information based on spatial databases and integrate with other information to provide users with required location-related *** development of systems based on MLBS has significance and practical *** this paper a visualization management information system for personnel in major events based on microservices,namely MEPMIS,is designed and implemented by using *** system consists of a server and a client app,and it has some functions including map search and query,personnel positioning and scheduling,location management,messaging,and location *** of the events can quickly search and locate the staff on the specific area of the map in real-time,and make broadcasting messages to the staff,and manage the *** client app is developed on the Android system,by which staff users can send the positions information to the server *** client users can search fuzzily near their peers and list their locations,and also call near peers through sending messages or query the history record of staff *** the design of the system,several new proposed techniques,including visual annotation method for overlapping locations,correcting trajectory drift algorithm,microservices-based overall system architecture methodology and other new techniques,which are applied to the implementation of the ***,HTML5,JQuery,MLBS APIs(Application Program Interfaces)related programming techniques have been used and combined with loading Ajax asynchronously and Json data encapsulation,map marker optimization techniques,that can improve the positioning accuracy and the performance of the *** developed system with practical functions can enhance the efficiencies of the organization and management of major events.

关键词： Mobile localization-based service(MLBS) map based search MLBS APIs visual location-based services(VLBS) personnel management major events

Raindrop Size Distributions in the Zhengzhou Extreme Rainfall Event on 20 July 2021:Temporal-Spatial Variability and Implications for Radar QPE

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Journal of Meteorological Research 2024年第3期38卷 489-503页

作者： Liman CUI haoran LI Aifang su Yang ZHANG Xiaona LYU Le XI Yuanmeng ZHANG Henan Key Laboratory of Agrometeorological support and Applied Technique China Meteorological AdministrationZhengzhou450003China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China Henan Meteorological Observatory Zhengzhou450003China

In this study,a regional Parsivel OTT disdrometer network covering urban Zhengzhou and adjacent areas is employed to investigate the temporal-spatial variability of raindrop size distributions(DSDs)in the Zhengzhou extreme rainfall event on 20 July *** rain rates observed by disdrometers and rain gauges from six operational sites are in good agreement,despite significant site-to-site variations of 24-h accumulated rainfall ranging from 198.3 to 624.1 *** Parsivel OTT observations show prominent temporal-spatial variations of DSDs,and the most drastic change was registered at Zhengzhou Station where the record-breaking hourly rainfall of 201.9 mm over 1500-1600 LST(local standard time)was *** hourly rainfall is characterized by fairly high concentrations of large raindrops,and the mass-weighted raindrop diameter generally increases with the rain rate before reaching the equilibrium state of DSDs with the rain rate of about 50 mm h^(−1).Besides,polarimetric radar observations show the highest differential phase shift(K_(dp))and differential reflectivity(Z_(dr))near surface over Zhengzhou Station from 1500 to 1600 *** light of the remarkable temporal-spatial variability of DSDs,a reflectivity-grouped fitting approach is proposed to optimize the reflectivity-rain rate(Z-R)parameterization for radar quantitative precipitation estimation(QPE),and the rain gauge measurements are used for *** results show an increase of mean bias ratio from 0.57 to 0.79 and a decrease of root-mean-square error from 23.69 to 18.36 for the rainfall intensity above 20.0 mm h^(−1),as compared with the fixed Z-R *** study reveals the drastic temporal-spatial variations of rain microphysics during the Zhengzhou extreme rainfall event and warrants the promise of using reflectivity-grouped fitting Z-R relationships for radar QPE of such events.

关键词： extreme rainfall raindrop size distribution radar quantitative precipitation estimation(QPE)

CO_2 methanation over TiO_2–Al_2O_3 binary oxides supported Ru catalysts

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Chinese Journal of Chemical Engineering 2016年第1期24卷 140-145页

作者： Jinghua Xu Qingquan Lin Xiong su Hongmin Duan haoran Geng Yanqiang Huang School of Materials Science and Engineering Shandong University State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences School of Chemistry and Chemical Engineering Yantai University Shandong Applied Research Center of Gold Nanotechnology (Au-SDARC)

TiO_2 modified Al_2O_3 binary oxide was prepared by a wet-impregnation method and used as the support for ruthenium catalyst. The catalytic performance of Ru/TiO_2–Al_2O_3catalyst in CO_2 methanation reaction was investigated. Compared with Ru/Al_2O_3 catalyst, the Ru/TiO_2–Al_2O_3catalytic system exhibited a much higher activity in CO_2 methanation reaction. The reaction rate over Ru/TiO_2–Al_2O_3 was 0.59 mol CO_2·(g Ru)1·h-1, 3.1 times higher than that on Ru/Al_2O_3[0.19 mol CO_2·(gRu)-1·h-1]. The effect of TiO_2 content and TiO_2–Al_2O_3calcination temperature on catalytic performance was addressed. The corresponding structures of each catalyst were characterized by means of H_2-TPR, XRD, and TEM. Results indicated that the averaged particle size of the Ru on TiO_2–Al_2O_3support is 2.8 nm, smaller than that on Al_2O_3 support of 4.3 nm. Therefore, we conclude that the improved activity over Ru/TiO_2–Al_2O_3catalyst is originated from the smaller particle size of ruthenium resulting from a strong interaction between Ru and the rutile-TiO_2 support, which hindered the aggregation of Ru nanoparticles.

关键词： CO2 methanation supported Ru catalyst TiO2–Al2O3 binary oxide

Observation of an acoustic non-Hermitian topological Anderson insulator

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Science China(Physics,Mechanics & Astronomy) 2023年第9期66卷 57-62页

作者： Zhongming Gu He Gao haoran Xue Di Wang Jiamin Guo Zhongqing su Baile Zhang Jie Zhu Institute of Acoustics School of Physics Science and EngineeringTongji UniversityShanghai 200092China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore 637371Singapore Centre for Disruptive Photonic Technologies Nanyang Technological UniversitySingapore 637371Singapore

The interaction of band topology and disorder can give rise to intriguing *** paradigmatic example is the topological Anderson insulator,whose nontrivial topology is induced in a trivial system by *** this study,we investigate the efect of purely non-Hermitian disorders on topological systems using a one-dimensional acoustic lattice with coupled ***,we construct a theoretical framework to describe the non-Hermitian topological Anderson insulator phase solely driven by disordered loss ***,the complete evolution of non-Hermitian disorder-induced topological phase transitions,from an initial trivial phase to a topological Anderson phase and finally to a trivial Anderson phase,is revealed experimentally using both bulk and edge ***,topological modes induced by non-Hermitian disorders to be immune to both weak Hermitian and non-Hermitian *** findings pave the way for future research on disordered non-Hermitian systems for novel wave manipulation.

关键词： topological Anderson insulator non-Hermitian systems topological edge states

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腐植酸在化肥农药减施增效中的应用

腐植酸 2019年第6期 10-14,36页

作者：朱莹雪李雪松刘思语苏浩然董禹含元野马献发东北农业大学资源与环境学院哈尔滨150030 中国烟草总公司黑龙江省分公司牡丹江烟草科学研究所哈尔滨150000

近几十年来,化肥农药的使用在农作物生产上取得显著的增产效果,但同时也带来了一系列的负面影响(土壤退化、土壤板结、土壤肥力降低等),并且已逐渐成为世界性问题。本文阐述了腐植酸特性及腐植酸类物质应用在化肥和农药上的减施增效作用... 详细信息

近几十年来,化肥农药的使用在农作物生产上取得显著的增产效果,但同时也带来了一系列的负面影响(土壤退化、土壤板结、土壤肥力降低等),并且已逐渐成为世界性问题。本文阐述了腐植酸特性及腐植酸类物质应用在化肥和农药上的减施增效作用,明确了腐植酸在化肥农药中的减施增效机制,展望了腐植酸的应用前景。

关键词：腐植酸化肥农药减施增效应用前景

The transition from 2G to 3G-feedstocks enabled efﬁcient production of fuelsand chemicals

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Green Energy & Environment 2024年第11期9卷 1759-1770页

作者： Kai Wang Changsheng su haoran Bi Changwei Zhang Di Cai Yanhui Liu Meng Wang Biqiang Chen Jens Nielsen Zihe Liu Tianwei Tan College of Life Science and Technology Beijing University of Chemical TechnologyBeijing Advanced Innovation Center for Soft Matter Science and EngineeringNo.15 North 3rd Ring Rd EastBeijing100029China National Energy R&D Center for Biorefnery Beijing Key Lab of BioprocessBeijing University of Chemical TechnologyNo.15 North 3rd Ring Rd EastBeijing100029China Department of Life Sciences Chalmers University of TechnologyGothenburgSE41296Sweden

For decades micoorganisms have been engineered for the utilization of lignocellulose-based second-generation (2G) feedstocks, but with theconcerns of increased levels of atmospheric CO_(2) causing global warming there is an emergent need to transition from the utilization of 2Gfeedstocks to third-generation (3G) feedstocks such as CO_(2) and its derivatives. Here, we established a yeast platform that is capable ofsimultaneously converting 2G and 3G feedstocks into bulk and value-added chemicals. We demonstrated that by adopting 3G substrates such asCO_(2) and formate, the conversion of 2G feedstocks could be substantially improved. Speciﬁcally, formate could provide reducing power andenergy for xylose conversion into valuable chemicals. Simultaneously, it can form a concentrated CO_(2) pool inside the cell, providing thermodynamically and kinetically favoured amounts of precursors for CO_(2) ﬁxation pathways, e.g., the Calvin–Benson–Bassham (CBB) ***, we demonstrated that formate could directly be utilized as a carbon source by yeast to synthesize endogenous amino acids. Theengineered strain achieved a one-carbon (C1) assimilation efﬁciency of 9.2%, which was the highest efﬁciency observed in the co-utilization of2G and 3G feedstocks. We applied this strategy for productions of both bulk and value-added chemicals, including ethanol, free fatty acids(FFAs), and longifolene, resulting in yield enhancements of 18.4%, 49.0%, and ~100%, respectively. The strategy demonstrated here for coutilization of 2G and 3G feedstocks sheds lights on both basic and applied research for the up-coming establishment of 3G bioreﬁneries.

关键词： transition utilized Benson