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Two decades of fire activity over the PEEX domain:a look from space,with contribution from models and ground-based measurements

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Big Earth Data 2024年第2期8卷 350-396页

作者： Larisa Sogacheva Timo H.Virtanen Anu-Maija Sundström Pekka Kolmonen Mikhail Sofiev Hanna K.Lappalainen antti Arola Finnish Meteorological Institute Climate Research ProgrammeHelsinkiFinland Finnish Meteorological Institute Space and Earth Observation CentreHelsinkiFinland Institute for Atmospheric and Earth System Research/Physics Faculty of ScienceUniversity of HelsinkiHelsinkiFinland

It has been suggested that forest fires will become more frequent/intense with changing climate,which would increase aerosol/gas emissions into the atmosphere.A better under-standing of the relations between meteorological conditions,fires,and fire emissions will help estimate the climate response via forest *** this study,we use ERA5 meteor-ological products,including temperature,precipitation,and soil moisture,to explain the frequency of forest fires and the amount of radiant energy released per time unit by burning vegetation(fire radiative power,FRP).We explore the relation-ships between satellite-retrieved fire products and aerosol properties(aerosol optical depth,AOD),carbon monoxide(CO),formaldehyde(HCHO),and nitrogen dioxide(NO_(2))con-centrations over the PEEX domain,which covers different vegetation zones(***/grasslands,forest,arctic tun-dra)of Pan-Eurasia and *** analyse the concentrations of black carbon and absorbing organic carbon using groundbased AErosol RObotic *** analysis covers the months of May to August from 2002 to *** show posi-tive temperature trends in the Northern zone(>65°N)in June and August(1.56°C and 0.64°C,respectively);all statistically significant trends for precipitation and soil moisture are *** can explain increased fire activity in Siberia over the recent years(2019-2022).Over the whole PEEX domain,FC and FRP trends remain insignificant or negative;a decrease in AOD may address those negative *** show that intrasummer variations exist for cropland/grassland fires,which occur most often in May and August,while Siberian forest fires occur more often in July and *** show that CO concentration has been gradually decreasing in the last two decades in May and *** trends are negative in May,June,and over summer for all regions,in July in Europe,China,the Southern zone(<55°N),and the PEEX *** trends are not significant in all ***_(2)trends are positive in May and

关键词： PEEX wild fires satellite trend enhancement ratios

Key aspects on the behaviour of the ballast and substructure of a modern railway track:research-based practical observations in Finland

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第11期13卷 825-835页

作者： antti NURMIKOLU Department of Civil Engineering Tampere University of TechnologyTampereFinland

This paper presents an overview on the wide-ranging track structure studies at the Tampere University of Technology(TUT),Finland dealing with the key aspects of track geotechnics related to high-speed passenger traffic on ballasted *** attention is paid to ballast and sub-ballast,while also considering frost action,embankment stability,track stiffness,track geometry and transition *** a result,this paper states that understanding the ballast degradation mechanism and its consequences and assessment of its condition occupy an important role in the construction and maintenance of a smooth high-speed rail *** choices related to building the sub-ballast also have a dramatic impact on later track deformations and maintenance *** cold climate,especially where seasonal frost occurs,understanding and taking into account the frost action mechanism is *** in the maintenance and rehabilitation planning of existing tracks,high-class analyses of ground penetrating radar data and its integrated analysis with other data can yield considerable benefits.

关键词： Railway Track Ballast Sub-ballast Substructure Subsoil Frost action Life cycle Ground penetrating radar

Study of methods for endpoint aware inspection in a next generation firewall

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Cybersecurity 2022年第4期5卷 56-70页

作者： Jenny Heino antti Hakkala Seppo Virtanen Department of Computing University of TurkuTurkuFinland Forcepoint LLC HelsinkiFinland

Given the global increase in remote work with the COVID-19 pandemic and deperimeterization due to cloud deployment of next generation frewalls,the concept of a next generation firewall is at a breaking *** is becoming more dificult to define the barrier between the good and the *** provide the best security for an endpoint with minimal false positives or false negatives it is often necessary to identify the communicating endpoint application.n this study,we present an analysis of key research and methods for providing endpoint aware protection in the context of a next generation frewall We examine both academic research as well as state-of-the-art of the existing next generation firewall *** divide endpoint application identification into passive and active *** passive endpoint application identification,we study several traffc fingerprinting methods for different *** active methods we consider active scanning,endpoint metadata analysis and content injection and reference existing *** conclude that there are several open areas for future research,and that none of the considered methods is a silver bullet solution for endpoint aware inspection in the context of a next generation *** our best knowledge,this is the first study to examine current research and existing implementations of endpoint aware inspection.

关键词： Network traffc Endpoint identification NGFW Endpoint aware inspection

NODAL O(h^4)-SUPERCONVERGENCE IN 3D BY AVERAGING PIECEWISE LINEAR,BILINEAR,AND TRILINEAR FE APPROXIMATIONS

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Journal of Computational Mathematics 2010年第1期28卷 1-10页

作者： antti Hannukainen Sergey Korotov Michal Krízek Institute of Mathematics Helsinki University of Technology Department of Mathematics Tampere University of Technology Institute of Mathematics Academy of Sciences

We construct and analyse a nodal O（h^4）-superconvergent FE scheme for approximating the Poisson equation with homogeneous boundary conditions in three-dimensional domains by means of piecewise trilinear functions. The scheme is based on averaging the equations that arise from FE approximations on uniform cubic, tetrahedral, and prismatic partitions. This approach presents a three-dimensional generalization of a two-dimensional averaging of linear and bilinear elements which also exhibits nodal O（h^4）-superconvergence （ultracon- vergence）. The obtained superconvergence result is illustrated by two numerical examples.

关键词： Higher order error estimates Tetrahedral and prismatic elements Supercon-vergence Averaging operators.

Recovering 3D structural properties of galaxies from SDSS-like photometry

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Research in Astronomy and Astrophysics 2015年第10期15卷 1613-1628页

作者： Elmo Tempel antti Tamm Rain Kipper Teeter Tenjes Tartu Observatory Institute of Physics University of Tartu

Because of the 3D nature of galaxies, an algorithm for constructing spatial density distribution models of galaxies on the basis of galaxy images has many advan- tages over approximations of the surface density distribution. We present a method for deriving the spatial structure and overall parameters of galaxies from images and estimate its accuracy and derived parameter degeneracies on a sample of idealised model galaxies. The test galaxies consist component with varying proportions and of a disc-like component and a spheroidal properties. Both components are assumed to be axially symmetric and coplanar. We simulate these test galaxies as if they had been observed in the SDSS project through ugriz filters, thus gaining a set of realis- tically imperfect images of galaxies with known intrinsic properties. These artificial SDSS galaxies were thereafter remodelled by approximating the surface brightness distribution with a 2D projection of a bulge＋disc spatial distribution model and the restored parameters were compared to the initial ones. Down to the r-band limiting magnitude of 18, errors in the restored integral luminosities and colour indices re- main within 0.05 mag and errors in the luminosities of individual components within 0.2 mag. Accuracy of the restored bulge-to-disc luminosity ratio （B/D） is within 40% in most cases, and becomes worse for galaxies with low B/D, but the general balance between bulges and discs is not shifted systematically. Assuming that the intrinsic disc axial ratio is ≤ 0.3, then the inclination angles can be estimated with errors 〈 5° for most of the galaxies with B/D 〈 2 and with errors 〈 15° up to B/D = 6. Errors in the recovered sizes of the galactic components are below 10% in most cases. The axial ratios and the shape parameter N of Einasto＇s distribution （similar to the Sersic index） are relatively inaccurate, but can provide statistical estimates for large samples. In general, models of disc components are more accurate than

关键词： methods: numerical -- galaxies: general -- galaxies: photometry --galaxies: structure

Label-free visualization of cholesteatoma in the mastoid and tympanic membrane using CARS microscopy

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Journal of Otology 2016年第3期11卷 127-133页

作者： Jing Zou antti Isomaki Timo Hirvonen antti Aarnisalo Jussi Jero Ilmari Pyykko Department of Otolaryngology-Head and Neck Surgery Center for Otolaryngology-Head&Neck Surgery of Chinese PLAChanghai HospitalSecond Military Medical University Hearing and Balance Research Unit Field of Oto-laryngologySchool of MedicineUniversity of Tampere Biomedicum Imaging Unit Faculty of MedicineUniversity of Helsinki Department of Otorhinolaryngology-Head and Neck Surgery Helsinki University Central Hospital

Objective:The present study aimed to evaluate the possibility of using coherent anti-Stokes Raman spectroscopy（CARS） microscopy to determine the specific molecular morphology of cholesteatoma by detecting the natural vibrational contrast of the chemical bonds without any *** and methods:Specimens from the mastoid and tympanic membrane with and without cholesteatoma were analyzed using CARS microscopy,two-photon excited fluorescence（TPEF） microscopy,and the second harmonic generation（SHG） ***:In cholesteatoma tissues from the mastoid,a strong resonant signal at 2845 cm;was observed by CARS,which indicated the detection of the CH;hydro-carbon lipid bonds that do not generate visible signals at 2940 cm;suggestive of CH;bonds in amino acids.A strong resonant signal at 2940 cm;appeared in an area of the same specimen,which also generated abundant signals by TPEF and SHG microscopy at 817 nm,which was suggestive of *** the tympanic membrane specimen with cholesteatoma,a strong resonant signal with corrugated morphology was detected,which indicated the presence of lipids.A strong signal was detected in the tympanic membrane with chronic otitis media using TPEF/SHG at 817 nm,which indicated collagen *** CARS and TPEF/SHG images were in accordance with the histology ***:These results suggest the need to develop a novel CARS microendoscope that can be used in combination with TPEF/SHG to distinguish cholesteatoma from inflammatory tissues.

关键词： Cholesteatoma Imaging Label-free Raman spectroscopy High resolution

Tonsillitis in children: unnecessary laboratory studies and antibiotic use

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世界儿科杂志:英文版 2016年第1期12卷 114-117页

作者： antti Kunnamo Matti Korppi Merja Helminen Pediatric Research Centre Tampere University and Univesity HospitalTampereFinland

Background:The Finnish Current Care Guidelines on diagnostics and treatment of sore throat recommend the treatment of only group A streptococcus(GAS)positive cases with *** aim of the study was to evaluate how these guidelines are followed in the pediatric emergency ***:We analyzed retrospectively the data on microbiological studies and blood tests done,and data on prescribing of antibiotics,of 200 children admitted for febrile exudative ***:After the clinical diagnosis of exudative tonsillitis,antigen test and/or culture for GAS identifi cation was done in>95%of *** the 32(16%)children with GAS infection,but also 52(38%)of the 137 children without any evidence of bacterial infection received *** laboratory studies were done in 96%of *** C-reactive concentrations or white blood cell counts were not able to separate streptococcal from non-streptococcal *** serious bacterial infection was ***:The Finnish Current Care Guidelines lead to over-treatment with *** of the 200 children returned after discharge,suggesting that undertreatment did not happen.

关键词： exudative tonsillitis streptococcal antigen test streptococcal culture

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阶梯停车场芬兰郝尔辛基

世界建筑导报 2024年第2期39卷 117-119页

作者： uho Grönholm antti Nousjoki Samuli Woolston Pekka Tainio Tuulikki Tanska Rachel Murray Anssi Luodemäki Harri Humppi Tuomas Uusheimo(摄影) Marc Goodwin(摄影) ALA建筑师事务所不详

新的五角形、五层高的Saukonlaituri停车设施包括六条流线,可停放600辆私家车,中央庭院被布满巨石、苔藓和蕨类植物的景观环绕。其中五个停车场有顶棚,第六个停车场位于屋顶。庭院具有双重功能:它既是一个采光井,阳光可通过庭院照射到... 详细信息

新的五角形、五层高的Saukonlaituri停车设施包括六条流线,可停放600辆私家车,中央庭院被布满巨石、苔藓和蕨类植物的景观环绕。其中五个停车场有顶棚,第六个停车场位于屋顶。庭院具有双重功能:它既是一个采光井,阳光可通过庭院照射到较低的停车场,又是雨水蓄水池和积雪堆积地。建筑的南侧从入口广场后退,将地面公共空间延伸为阶梯式公园,一直延伸到屋顶。这种解决方案使周围公寓楼的居民可以沿着阶梯走到正确的楼层取车,而不是乘坐电梯。阶梯区域也可以用于野餐和日光浴。

关键词：入口广场空间延伸采光井停车设施公寓楼停车场阶梯式电梯

Linear Connectivity, Schwarz–Pick Lemma and Univalency Criteria for Planar Harmonic Mapping

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Acta Mathematica Sinica,English Series 2016年第3期32卷 297-308页

作者： Shao Lin CHEN Saminathan PONNUSAMY antti RASILA Xian Tao WANG Department of Mathematics and Computational Science Hengyang Normal University Indian Statistical Institute (ISI) Chennai CentreSETS (Society for Electronic Transactions and Security)MGR Knowledge CityCIT Campus Department of Mathematics and Systems Analysis Aalto University Department of Mathematics Shantou University

In this paper, we first establish a Schwarz-Pick lemma for higher-order derivatives of planar harmonic mappings, and apply it to obtain univalency criteria. Then we discuss distortion theorems, Lipschitz continuity an... 详细信息

关键词： Harmonic mapping linearly connected domain Schwarz-Pick lemma a-close-to-convex function John constant univalency