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Inventory of aspen trees in spruce dominated stands in conserva-tion area

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Forest Ecosystems 2015年第2期2卷 143-154页

作者： Matti Maltamo Annukka Pesonen Lauri Korhonen Jari Kouki mikko Vehmas Kalle Eerik?inen University of Eastern Finland School of Forest Science Blom Kartta Oy City of Joensuu Natural Resources Institute Finland Joensuu Unit

Background： The occurrence of aspen trees increases the conservation value of mature conifer dominated forests. Aspens typically occur as scattered individuals among major tree species, and therefore the inventory of aspens is challenging. Methods： We characterized aspen populations in a boreal nature reserve using diameter distribution, spatial pattern, and forest attributes： volume, number of aspens, number of large aspen stems and basal area median diameter. The data were collected from three separate forest stands in Koli National Park, eastern Finland. At each site, we measured breast height diameter and coordinates of each aspen. The comparison of inventory methods of aspens within the three stands was based on simulations with mapped field data. We mimicked stand level inventory by locating varying numbers of fixed area circular plots both systematically and randomly within the stands. Additionally, we also tested if the use of airborne laser scanning （ALS） data as auxiliary information would improve the accuracy of the stand level inventory by applying the probability proportional to size sampling to assist the selection of field plot locations. Results： The results showed that aspens were always clustered, and the diameter distributions indicated different stand structures in the three investigated forest stands. The reliability of the volume and number of large aspen trees varied from relative root mean square error figures above 50% with fewer sample plots （5-10） to values of 25%-50% with ]0 or more sample plots. Stand level inventory estimates were also able to detect spatial pattern and the shape of the diameter distribution. In addition, ALS-based auxiliary information could be useful in guiding the inventories, but caution should be used when applying the ALS-supported inventory technique. Conclusions： This study characterized European aspen populations for the purposes of monitoring and management of boreal conservation areas. Our results suggest tha

关键词： Diameter distribution Historical continuity Inventory LiDAR Populus tremula L Simulation Spatial arrangement Stand characteristics

Comparison of the local pivotal method and systematic sampling for national forest inventories

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Forest Ecosystems 2020年第4期7卷 716-732页

作者： Minna Räty mikko Kuronen Mari Myllymäki Annika Kangas Kai Mäkisara Juha Heikkinen Natural Resources Institute Finland(Luke) PO Box 2FI-00791 HelsinkiFinland. Natural Resources Institute Finland(Luke) Yliopistokatu 6FI-80100 JoensuuFinland

Background:The local pivotal method(LPM)utilizing auxiliary data in sample selection has recently been proposed as a sampling method for national forest inventories(NFIs).Its performance compared to simple random sampling(SRS)and LPM with geographical coordinates has produced promising results in simulation *** this simulation study we compared all these sampling methods to systematic *** LPM samples were selected solely using the coordinates(LPMxy)or,in addition to that,auxiliary remote sensing-based forest variables(RS variables).We utilized field measurement data(NFI-field)and Multi-Source NFI(MS-NFI)maps as target data,and independent MS-NFI maps as auxiliary *** designs were compared using relative efficiency(RE);a ratio of mean squared errors of the reference sampling design against the studied *** a method in NFI also requires a proven estimator for the ***,three different variance estimators were evaluated against the empirical variance of replications:1)an estimator corresponding to SRS;2)a Grafström-Schelin estimator repurposed for LPM;and 3)a Matérn estimator applied in the Finnish NFI for systematic sampling ***:The LPMxy was nearly comparable with the systematic design for the most target *** REs of the LPM designs utilizing auxiliary data compared to the systematic design varied between 0.74–1.18,according to the studied target *** SRS estimator for variance was expectedly the most biased and conservative ***,the Grafström-Schelin estimator gave overestimates in the case of *** the RS variables were utilized as auxiliary data,the Grafström-Schelin estimates tended to underestimate the empirical *** systematic sampling the Matérn and Grafström-Schelin estimators performed for practical purposes ***:LPM optimized for a specific variable tended to be more efficient than systematic sampling,but all of the considered LPM designs were

关键词： Auxiliary data Bias Local pivotal method Matérn estimator National forest inventory Sampling efficiency Simple random sampling Spatially balanced sampling Systematic sampling Variance

Optimal energy-efficient scheme for two-way relay channel using physical layer network coding

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The Journal of China Universities of Posts and Telecommunications 2011年第6期18卷 51-58页

作者： ZHOU Min CUI Qi-mei WANG Hui TAO Xiao-feng TIAN Hui mikko Valkama Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Beijing 100876 China Department of Communications Engineering Tampere University of Technology Tampere PF1-33101 Finland

Systems are always designed and optimized based on full traffic load in the current literatures. However, practical systems are seldom operating at full load, even at peak traffic hours. Instead of maximizing system rate to achieve the full load, an optimal energy-efficient scheme to minimize the transmit power with required rates is investigated in this article. The considered scenario is a two-way relay channel using amplify-and-forward protocol of physical layer network coding, where two end nodes exchange messages via multiple relay nodes within two timeslots. A joint power allocation and relay selection scheme is designed to achieve the minimum transmit power. Through convex optimization theory, we firstly prove that single relay selection scheme is the most energy-efficient way for physical layer network coding. The closed-form expressions of power allocation are also given. Numerical simulations demonstrate the performance of the designed scheme as well as the comparison among different schemes.

关键词： energy-efficient two-way relay channel physical layer network coding power allocation relay selection rate constraints

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基于反向方法的船体冰载荷研究（英文）

船舶力学 2016年第12期20卷 1604-1618页

作者：刘瀛昊 SUOMINEN mikko KUJALA Pentti 哈尔滨工程大学船舶工程学院哈尔滨150001 阿尔托大学应用力学系船舶技术实验室芬兰15300

船舶碰撞海冰引起的冰载荷分布是十分复杂的。文章选取Thikhonov正则化这一反向方法,根据极地科考补给船S.A Agulhas II号于2013-2014年间南极航行时实测的数据,分析得到了船体艉肩部的冰载荷。通过应用三种独立的冰载荷离散方式来模拟... 详细信息

船舶碰撞海冰引起的冰载荷分布是十分复杂的。文章选取Thikhonov正则化这一反向方法,根据极地科考补给船S.A Agulhas II号于2013-2014年间南极航行时实测的数据,分析得到了船体艉肩部的冰载荷。通过应用三种独立的冰载荷离散方式来模拟海冰的自然特性,在有限元中得到模型的影响矩阵,并应用Matlab对Thikhonov正则化方程进行了优化。研究结果表明,反向方法可以克服数据处理过程中的不适定性,并计算得到船体冰载荷。

关键词：冰载荷有限元方法(FEM) Thikhonov正则化载荷离散反向方法

Quantitative in situ measurement of optical force along a strand of cleaved silica optical fiber induced by the light guided therewithin

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Photonics Research 2021年第10期9卷 2016-2023页

作者： mikko PARTANEN HYEONWOO LEE KYUNGHWAN OH Photonic Device Physics Laboratory Department of PhysicsYonsei UniversitySeoul 03722Republic of Korea Photonics Group Department of Electronics and NanoengineeringAalto University00076 AaltoFinland

We propose an optomechanical system to quantify the net force on a strand of cleaved silica optical fiber in situ as the laser light is being guided through *** strands of the fiber were bonded to both sides of a macroscopic oscillator,whose movements were accurately monitored by a Michelson *** laser light was propagating with variable optical powers and frequency ***,we discovered that the driving force for the oscillator consisted of not only the optical force of the light exiting from the cleaved facets but also the tension along the fiber induced by the light guided *** net driving force was determined only by the optical power,refractive index of the fiber,and the speed of light,which pinpoints its fundamental origin.

关键词： fiber optical interferometer

Metallic mineral deposits in the Nordic countries

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Episodes 2008年第1期31卷 125-132页

作者： Paer Weihed Pasi Eilu Rune B. Larsen Henrik Stendal mikko Tontti Division of Ore Geology and Applied Geophysics Lulea University of Technology SE-971 87 Lulea Sweden. Geological Survey of Finland PO Box 96 FI-02151 Espoo Finland. NTNU NO-7491 Trondheim Norway. Geological Survey of Denmark and Greenland Ф. Voldgade 10 DK-1350 Cph. Denmark.

The Nordic countries, including Greenland, have a long tradition in mining. Documented mining dates back to the 8th century AD. Today this region is the most important metallic mining district of the European Union. Metals are produced from active mines in all countries except Iceland and related industries are thriving in all countries. Important ore deposit types include： volcanogenic massive sulphide deposits （Cu, Zn, Pb, Au, Ag）, orogenic gold deposits （Au）, layered intrusions （Ni, PGE, Ti±V）, intrusive hosted Cu-Au, apatite-Fe deposits, Cr- and anorthosite hosted Ti deposits. Besides these well- documented deposits, new kinds of deposits are being explored, e.g., iron oxide-copper-gold （IOCG）, shale-hosted Ni-Zn-Cu and different types of uranium deposits.

关键词：金属矿物资源储备北欧地区资源开发

Incidence of pediatric injury visits decreased while trauma surgeries remained stable during the first and second waves of the COVID-19 pandemic in Finland:a register-based study

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World Journal of Pediatric Surgery 2021年第4期4卷 47-51页

作者： Joonas Kuorikoski Ilari Kuitunen mikko Uimonen Ville M Mattila Ville Ponkilainen Department of Surgery Central Finland Central HospitalJyvaskylaFinland Department of Pediatrics Mikkeli Central HospitalMikkeliFinland Department of Pediatrics University of Eastern FinlandMikkeliFinland Department of Orthopaedics and Traumatology Tampere University HospitalTampereFinland Faculty of Medicine and Health Technology Tampere UniversityTampereFinland

Introduction The COVID-19 pandemic has reduced pediatric emergency department(ED)visits and *** study evaluates the incidence of pediatric trauma ED visits and surgeries in Finland during the first and second waves of the *** Three large Finnish hospitals,covering one-sixth of the Finnish pediatric population,*** on all ED visits and trauma surgeries between January 2017 and December 2020 were collected from hospital discharge *** incidences with 95%CI were calculated per 100000 person-months by Poisson exact method and compared by incidence rate ratio(IRR).Results During the lockdown the incidence of head injuries(IRR 0.19,95%CI 0.04 to 0.87),sprains(IRR 0.25,95%CI 0.14 to 0.46),and fractures(IRR 0.36,95%CI 0.25 to 0.51)decreased in the 13-17 years age *** the 4-12 years age group a 55%decrease(IRR 0.45,95%CI 0.22 to 0.96)in head injuries was *** the period of regional restrictions a subtle decrease in head injuries was seen in the 13-17 years age group(IRR 0.26,95%CI 0.09 to 0.78).During the lockdown in March 2020 the incidence of fractures decreased in the oldest age group(13-17 years)(IRR 0.62,95%CI 0.46 to 0.85),while a rebound in incidence was seen at the end of the lockdown period in *** The nationwide lockdown and the cancellation of sports and other hobbies markedly decreased the injuries among children aged 13-17 years,while the decrease was lower among children aged 4-12 *** of sports and hobbies did not affect patients under 4 years of age.

关键词： injuries pediatric markedly

Deciphering the Origin and Formation of Aminopyrrole Moiety in Kosinostatin Biosynthesis

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Chinese Journal of Chemistry 2021年第12期39卷 3329-3333页

作者： Yu Hu Qiang Zhou Zhuan Zhang Hai-Xue Pan Yulia Ilina mikko Metsa-Ketela Yasuhiro Igarashi Gong-Li Tang State Key Laboratory of Bio-organic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences(CAS)CASShanghai 200032China The Research Center of Chiral Drugs Innovation Research Institute of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai 201203China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences1 Sub-lane XiangshanHangzhouZhejiang 310024China Department of Biochemistry University of TurkuVatselankatu 2FIN-20014Finland Biotechnology Research Center Toyama Prefectural University 5180 KurokawaImizuToyama 939-0398Japan

Kosinostatin(KST)contains an uncommon aminopyrrole moiety,whose biosynthesis has remained ***,aminopyrrolinic acid,which was generated by an L-ectoine synthase-like enzyme KstB3 via cyclization of L-glutamine,was identified to be the real substrate of adenylation enzyme ***,a FAD-dependent dehydrogenase KstB4 along with a transglutaminase-like enzyme KstB6 were also involved in formation of *** results provided an unusual pathway for 2-aminopyrrole formation in KST biosynthesis.

关键词： Biosynthesis Aminopyrrole Kosihbstatin Cyclization Hydrolysis

Myofibroblastic cell activation and neovascularization predict native liver survival and development of esophageal varices in biliary atresia

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World Journal of Gastroenterology 2014年第12期20卷 3312-3319页

作者： Janne S Suominen Hanna Lampela Pivi Heikkil Jouko Lohi Hannu Jalanko mikko P Pakarinen Department of Pediatric Surgery Pediatric Liver and Gut Research GroupChildren’s HospitalUniversity of Helsinki Department of Pathology HUSLABHelsinki University Central Hospital Department of Paediatrics Children’s HospitalHelsinki University Central Hospital

AIM: To study the relation between collagen 1, α-smooth muscle actin (α-SMA) and CD34 expression and the most essential portoenterostomy (PE) outcomes.

关键词： Biliary atresia, Liver fibrosis, Neovascularization, Collagen 1, α -smooth muscle actin, CD34