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High-resolution photogrammetry to measure physical aperture of two separated rock fracture surfaces

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2922-2934页

作者： Masoud Torkan Mateusz Janiszewski lauri Uotinen Alireza Baghbanan Mikael Rinne Department of Civil Engineering Aalto UniversityEspooFinland Department of Mining Engineering Isfahan University of TechnologyIsfahanIran

Photogrammetry,reconstructing three-dimensional(3D)models from overlapping two-dimensional(2D)photos,finds application in rock mechanics and rock engineering to extract geometrical details of reconstructed objects,for example rock *** properties are important for determining the mechanical stability,permeability,strength,and shear behavior of the rock *** can be used to reconstruct detailed 3D models of two separated rock fracture surfaces to characterize fracture roughness and physical aperture,which controls the fluid flow,hydromechanical and shear behavior of the rock *** research aimed to determine the optimal number of scale bars required to produce high-precision 3D models of a fracture surface.A workflow has been developed to define the physical aperture of a fracture using *** blocks of Kuru granite(25 cm×25 cm×10 cm)with an artificially induced fracture,were *** scaling 3D models,321 markers were used as ground control points(GCPs)with predefined distances on each *** the samples were wellmatched in their original positions,the entire block was *** data of the GCPs were extracted from the 3D model of the *** half was surveyed separately and georeferenced by GCPs and merged into the same coordinate *** fracture surfaces were extracted from the 3D models and the vertical distance between the two surfaces was digitally calculated as physical *** assessment of the photogrammetric reconstruction showed a 20-30 mm digital control distance accuracy when compared to known distances defined between *** attain this accuracy,the study found that at least 200 scale bars were ***,photogrammetry was employed to measure changes in aperture under normal *** results obtained from this approach were found to be in good agreement with those obtained using linear variable displacement transducers(LVDTs),with differences ran

关键词： Photogrammetry Physical aperture Rock fracture Predefined distances Markers

Microscopic analysis on eukaryotic algae and cyanobacteria in nine seasonal lakes and ponds in Vestfjella,Dronning Maud Land,Antarctica

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Advances in Polar Science 2024年第2期35卷 206-218页

作者： lauri ARVOLA Matti LEPPÄRANTA LI Zhijun Lammi Biological Station University of HelsinkiLammi FI-16900Finland Department of Physics University of HelsinkiHelsinki FI-00014Finland State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116023China

Antarctic continental lakes and ponds are among the most impoverished aquatic environments on earth but many of them support flourishing populations of cyanobacteria,eukaryotic algae,protozoans,and some multicellular *** this study,we present results of a microscopic analysis of cyanobacteria and eukaryotic algae from nine diverse types of Antarctic continental water bodies during one austral *** results supplement and enlarge our previous studies on the limnological characteristics of the epiglacial and supraglacial lakes and ponds in Dronning Maud Land,an area that has received little attention from *** taxon with highest frequency among the samples(n=79)was Mesotaenium ***,a eukaryotic Zygnematophyceae,which occurred in 82%of the samples with a maximum cell density of 68 cells·mL^(-1).The taxa with second and third highest frequency were the prokaryotes Gloeocapsopsis(60%)and Leptolyngbya(41%),followed by Chlamydomonas(34%)and Cyanothece(29%).The number of taxa varied between 7-21 among the lakes and ponds,being highest in a supraglacial lake,and lowest in an epiglacial *** results did not reveal any obvious correlation between the abundance of any taxa and the water chemistry,but water bodies with inorganic sediments had higher cell densities and biomasses than those without *** suggests the importance of sediment in supporting biological diversity in these ultraoligotrophic lakes and ponds.

关键词： Antarctic continental lakes Antarctic continental ponds cyanobacteria algae protozoa rotifers tardigrada

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乌梁素海湖冰完整生消过程的数值模拟

水科学进展 2024年第1期35卷 145-155页

作者：霍璞真卢鹏解飞王庆凯李志军 ARVOLA lauri 大连理工大学海岸和近海工程国家重点实验室辽宁大连116024 Lammi Biological Station University of HelsinkiHelsinkiFI-16900Finland

为探究气候变暖背景下乌梁素海湖冰的冰厚、冰温和冰物候特征的变化,利用ERA5-Land和MERRA-2再分析数据作为大气强迫场,结合多源卫星遥感反演得到的初始模拟日期,通过一维高分辨率热力学雪冰(HIGHTSI)模型模拟了2015—2016年乌梁素海湖... 详细信息

为探究气候变暖背景下乌梁素海湖冰的冰厚、冰温和冰物候特征的变化,利用ERA5-Land和MERRA-2再分析数据作为大气强迫场,结合多源卫星遥感反演得到的初始模拟日期,通过一维高分辨率热力学雪冰(HIGHTSI)模型模拟了2015—2016年乌梁素海湖冰的完整生消过程。结果显示:①研究期内,最大冰厚达到41.7 cm,初冰日和终冰日分别为2015年11月21日和2016年3月25日,冰期为126 d。②对于水深较浅而冬季日照充足的乌梁素海,气温是影响冰厚的主要因素,太阳辐射次之,两者的昼夜周期循环显著影响冰层的厚度和温度;当冰面有雪覆盖时,积雪的低导热和高反照率会明显削弱气温和太阳辐射对冰层的影响。③即使缺失现场观测数据,采用气象数据和遥感反演的初始模拟日期仍能准确地表征现场真实冰雪的完整演变过程。该研究可为中纬度干旱区季节性冰封浅水湖冰的计算和湖冰生消的年际变化研究奠定基础。

关键词：湖冰完整生消过程再分析数据卫星遥感 HIGHTSI模型乌梁素海

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未来十年,决定中国碳排放的两个关键

能源 2024年第6期 50-54页

作者： lauri Myllyvirta 亚洲协会政策研究院(Asia Society Policy Institute) 能源与清洁空气研究中心(CREA)

这关系着如何让碳达峰尽可能的低,以便于更好地碳中和。中国温室气体排放占全球排放量的30%。自2015年巴黎协议签署以来,中国的碳排放增长占全球排放增长的90%。中国在未来十年内实现碳达峰并大幅减排,对于全球碳排放下降以及实现巴黎... 详细信息

这关系着如何让碳达峰尽可能的低,以便于更好地碳中和。中国温室气体排放占全球排放量的30%。自2015年巴黎协议签署以来,中国的碳排放增长占全球排放增长的90%。中国在未来十年内实现碳达峰并大幅减排,对于全球碳排放下降以及实现巴黎协定制定的目标至关重要。

关键词：碳排放碳中和巴黎协定温室气体排放巴黎协议未来十年排放量全球

2023年,清洁能源成为中国经济的主要驱动力

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能源 2024年第2期 73-80页

作者： lauri Myllyvirta Qi Qin 能源与清洁空气研究中心(CREA) 亚洲社会政策研究所(ASPI) 能源与清洁空气研究中心

2023年,清洁能源为中国经济贡献了11.4万亿人民币(约合1.6万亿美元),使得该行业在经济增长中所占比重稳居首位。根据官方数据和行业数据的分析显示,去年中国清洁能源投资大幅增长。“新三样”(即新能源汽车、锂电池和太阳能)成为投资的... 详细信息

2023年,清洁能源为中国经济贡献了11.4万亿人民币(约合1.6万亿美元),使得该行业在经济增长中所占比重稳居首位。根据官方数据和行业数据的分析显示,去年中国清洁能源投资大幅增长。“新三样”(即新能源汽车、锂电池和太阳能)成为投资的主要热点。在分析中,我们采用了广义的“清洁能源”定义,包括可再生能源、核能、电网、储能、新能源汽车和铁路。这些都是中国在生产和能源使用中减少碳排放所需的技术和基础设施。

关键词：新能源汽车可再生能源能源使用清洁能源基础设施官方数据锂电池大幅增长

Single-emitter super-resolved imaging of radiative decay rate enhancement in dielectric gap nanoantennas

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Light(Science & Applications) 2024年第1期13卷 47-54页

作者： R.Margoth Córdova-Castro Bart van Dam Alberto lauri Stefan A.Maier Riccardo Sapienza Yannick De Wilde Ignacio Izeddin Valentina Krachmalnicoff Institut Langevin ESPCI ParisPSL UniversityCNRSParisFrance The Blackett Laboratory Department of PhysicsImperial College LondonLondonUK School of Physics and Astronomy Monash UniversityClaytonVictoriaAustralia Chair in Hybrid Nanosystems Ludwig-Maximilians Universität MünchenMuenchenGermany Department of Physics University of OttawaOttawaONCanada

High refractive index dielectric nanoantennas strongly modify the decay rate via the Purcell effect through the design of radiative *** to their dielectric nature,the field is mainly confined inside the nanostructure and in the gap,which is hard to probe with scanning probe *** we use single-molecule fluorescence lifetime imaging microscopy(smFLIM)to map the decay rate enhancement in dielectric GaP nanoantenna dimers with a median localization precision of 14 *** measure,in the gap of the nanoantenna,decay rates that are almost 30 times larger than on a glass *** comparing experimental results with numerical simulations we show that this large enhancement is essentially radiative,contrary to the case of plasmonic nanoantennas,and therefore has great potential for applications such as quantum optics and biosensing.

关键词： dielectric decay radiative

Why on the snow？ Winter emergence strategies of snow-active Chironomidae （Diptera） in Poland

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Insect Science 2016年第5期23卷 754-770页

作者： Agnieszka Soszynska-Maj lauri Paasivirta Wojciech Gilka Faculty of Biology and Environmental Protection Department of Invertebrate Zoology and Hydrobiology University of Lodz Banacha 12116 90-237 Lodz Poland Ruuhikoskenkatu 17 B 5 FIN-24240 Salo Finland Department of Invertebrate Zoology and Parasito- logy University of Gdansk Wita Stwosza 59 80-308 Gdansk Poland

A long-term study of adult non-biting midges （Chironomidae） active in winter on the snow in mountain areas and lowlands in Poland yielded 35 species. The lowland and mountain communities differed significantly in their specific composition. The mountain assemblage was found to be more diverse and abundant, with a substantial contribution from the subfamily Diamesinae, whereas Orthocladiinae predominated in the lowlands. Orthocladius wetterensis Brundin was the most characteristic and superdominant species in the winter-active chironomid communities in both areas. Only a few specimens and species of snow-active chironomids were recorded in late autumn and early winter. The abundance ofchironomids peaked in late February in the mountain and lowland areas with an additional peak in the mountain areas in early April. However, this second peak of activity consisted mainly of Orthocladiinae, as Diamesinae emerged earliest in the season. Most snow-active species emerged in mid- and late winter, but their seasonal patterns differed between the 2 regions as a result of the different species composition and the duration of snow cover in these regions. Spearman＇s rank correlation coefficient tests yielded positive results between each season and the number of chironomid individuals recorded in the mountain area. A positive correlation between air temperature, rising to ＋3.5 ~C, and the number of specimens recorded on the snow in the mountain community was statistically significant. The winter emergence and mate-searching strategies of chironomids are discussed in the light of global warming, and a brief compilation of most important published data on the phenomena studied is provided.

关键词： Chironomidae Diamesinae Diptera Orthocladiinae snow activity weather influence winter emergence

Zero Hour and the Changing Same: Aesthetic Modernism and Black Nationalist Identity

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Journal of Foreign Languages and Cultures 2020年第1期4卷 99-113页

作者： lauri Scheyer Hunan Normal University

What is the meaning of Zero Hour for African Americans?The Zero Hour of May 8,1945 was a celebratory moment to mark“the victory of the cause of freedom,”in the immortal words of Winston *** what could Zero Hour signify for African Americans who continued to encounter racist and discriminatory practices at the end of the war and into the present?The history of African Americans has been characterized by series of“victories for freedom,”“new beginnings,”“forward progress,”and“breaks with the past.”How many other Zero Hours can we identify in the history of Black people in the U.S.?Examining 20205s moment of pandemic and protests in relation to race and class,I ask what any Zero Hour means for African Americans who have encountered many promising milestones of liberation that fell short of the expected rights and *** literary examples including Gwendolyn Brooks,Amiri Baraka,Ray Durem,Langston Hughes,Frederick Douglass,and Anne Spencer,I propose that African American history has been marked by a long line of Zero Hours that have indeed achieved progress yet never fully realized the goal of just and fair equality of treatment and opportunity.

关键词： Freedom World War II African Americans protest race

Predicting stand age in managed forests using National Forest Inventory field data and airborne laser scanning

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Forest Ecosystems 2020年第3期7卷 579-589页

作者： Matti Maltamo Hermanni Kinnunen Annika Kangas lauri Korhonen University of Eastern Finland School of Forest SciencesP.O.Box 11180101JoensuuFinland Natural Resources Institute Finland Bioeconomy and EnvironmentP.O.Box 6880100JoensuuFinland

Background: The aim of this study was to construct a nationwide stand age model by using National Forest Inventory(NFI) data and nationwide airborne laser scanning(ALS) data. In plantation forestry, age is usually *** this is not the case in boreal managed forests, age is still seldom predicted in forest management *** age accurately in situ is also very laborious. On the other hand, tree age is one of the accurately measured sample tree attributes in NFI field data. Many countries also have a nationwide coverage of airborne laser scanning(ALS) data. In this study, we merged these data sources and constructed a nationwide, area-based model for stand ***: While constructing the model, we omitted old forests from the data, since the correlation between ALS height metrics and stand age diminished at stands with age > 100 years. Additionally, the effect of growth conditions was considerable, so we also utilized different geographical and NFI variables such as site fertility and soil type in the modeling. The resultant nationwide model for the stand age of managed forests yielded a root mean square error(RMSE) of about 14 years. The model could be improved further by additional forest structure variables, but such information may not be available in ***: The results showed that the prediction of stand age by ALS, geographical and NFI information was challenging, but stil possible with moderate success. This study is an example of the joint use of NFI and nationwide ALS data and re-use of NFI data in research.

关键词： Forest stock age LiDAR NFI Nationwide model Growth conditions