Ruokohelvestä uusi tietopaketti nettisivuilla

Ruokohelvestä energiaa -nettisivusto on julkaistu. Sivuilla kerrotaan kattavasti ruokohelvestä, sen viljelystä, käytöstä voimaloissa ja tutkimuksesta. Viljelystä kiinnostuneet ihmiset löytävät nyt tärkeää tietoa niin ruokohelven siementoimittajista, urakoitsijoista kuin ostajistakin kätevästi samasta paikasta. Koko ketju on edustettuna.vo

New silicon photonics integration platform enabled by novel micron-scale bends

Even though submicron silicon waveguides have been proposed for dense integration of photonic devices, to date the lightwave circuits on the market mainly rely on waveguides with micron-scale core dimensions. These larger waveguides feature easier fabrication, higher reliability and better interfacing to optical fibres. Single-mode operation with large core dimensions is obtained with low lateral refractive index contrast. Hence, the main limitation in increasing the level of integration and in reducing the cost of micron-scale waveguide circuits is their mm- to cm-scale minimum bending radius. Fortunately, single-mode rib waveguides with a micron-scale silicon core can be locally transformed into multi-mode strip waveguides that have very high lateral index contrast. Here we show how Euler spiral bends realized with these waveguides can have bending radii below 10 {\mu}m and losses below 0.02 dB/90{\deg} for the fundamental mode, paving way for a novel densely integrated platform based on micron-scale waveguides.Comment: 14 pages, 29 Refs., 5 Fig

Ruokohelvestä energiaa -hankkeet viisinkertaistivat viljelyalat Pohjanmaalla

Voimalaitokset kiinnostuivat ruokohelvestä polttoaineena Kioton ilmastosopimuksen ja sitä seuranneen päästökaupan alkamisen takia. Ruokohelpi on kuitenkin sekä voimalaitoksille että viljelijöille uusi kasvi, joten tutkimukselle ja neuvonnalle on ollut tarvetta.vo

Low-error and broadband microwave frequency measurement in a silicon chip

Instantaneous frequency measurement (IFM) of microwave signals is a fundamental functionality for applications ranging from electronic warfare to biomedical technology. Photonic techniques, and nonlinear optical interactions in particular, have the potential to broaden the frequency measurement range beyond the limits of electronic IFM systems. The key lies in efficiently harnessing optical mixing in an integrated nonlinear platform, with low losses. In this work, we exploit the low loss of a 35 cm long, thick silicon waveguide, to efficiently harness Kerr nonlinearity, and demonstrate the first on-chip four-wave mixing (FWM) based IFM system. We achieve a large 40 GHz measurement bandwidth and record-low measurement error. Finally, we discuss the future prospect of integrating the whole IFM system on a silicon chip to enable the first reconfigurable, broadband IFM receiver with low-latency.Comment: 13 pages, 7 figure

Sensitivity of 21st century simulated ecosystem indicators to model parameters, prescribed climate drivers, RCP scenarios and forest management actions for two Finnish boreal forest sites

Forest ecosystems are already responding to changing environmental conditions that are driven by increased atmospheric CO2 concentrations. These developments affect how societies can utilise and benefit from the woodland areas in the future, be it for example climate change mitigation as carbon sinks, lumber for wood industry, or preserved for nature tourism and recreational activities. We assess the effect and the relative magnitude of different uncertainty sources in ecosystem model simulations from the year 1980 to 2100 for two Finnish boreal forest sites. The models used in this study are the land ecosystem model JSBACH and the forest growth model PREBAS. The considered uncertainty sources for both models are model parameters and four prescribed climates with two RCP (representative concentration pathway) scenarios. Usually, model parameter uncertainty is not included in these types of uncertainty studies. PREBAS simulations also include two forest management scenarios. We assess the effect of these sources of variation at four different points in time on several ecosystem indicators, e.g. gross primary production (GPP), ecosystem respiration, soil moisture, recurrence of drought, length of the vegetation active period (VAP), length of the snow melting period and the stand volume. The uncertainty induced by the climate models remains roughly the same throughout the simulations and is overtaken by the RCP scenario impact halfway through the experiment. The management actions are the most dominant uncertainty factors for Hyytiala and as important as RCP scenarios at the end of the simulations, but they contribute only half as much for Sodankyla. The parameter uncertainty is the least influential of the examined uncertainty sources, but it is also the most elusive to estimate due to non-linear and adverse effects on the simulated ecosystem indicators. Our analysis underlines the importance of carefully considering the implementation of forest use when simulating future ecosystem conditions, as human impact is evident and even increasing in boreal forested regions.Peer reviewe

Consistent estimates of gross primary production of Finnish forests : comparison of estimates of two process models

201

Newtonian boreal forest ecology : The Scots pine ecosystem as an example

Isaac Newton's approach to developing theories in his book Principia Mathematica proceeds in four steps. First, he defines various concepts, second, he formulates axioms utilising the concepts, third, he mathematically analyses the behaviour of the system defined by the concepts and axioms obtaining predictions and fourth, he tests the predictions with measurements. In this study, we formulated our theory of boreal forest ecosystems, called NewtonForest, following the four steps introduced by Newton. The forest ecosystem is a complicated entity and hence we needed altogether 27 concepts to describe the material and energy flows in the metabolism of trees, ground vegetation and microbes in the soil, and to describe the regularities in tree structure. Thirtyfour axioms described the most important features in the behaviour of the forest ecosystem. We utilised numerical simulations in the analysis of the behaviour of the system resulting in clear predictions that could be tested with field data. We collected retrospective time series of diameters and heights for test material from 6 stands in southern Finland and five stands in Estonia. The numerical simulations succeeded to predict the measured diameters and heights, providing clear corroboration with our theory.Peer reviewe

Association of short poor work ability measure with increased mortality risk : a prospective multicohort study

Publisher Copyright: © Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY. Published by BMJ.OBJECTIVES: To examine whether a single-item measure of self-rated work ability predicts all-cause mortality in three large population-based samples collected in 1978-1980, 2000 and 2017. SETTING: A representative sample of the population of Finland. PARTICIPANTS: The study population comprised 17 178 participants aged 18 to 65 from the population-based Mini-Finland, Health 2000 and FinHealth 2017 cohort studies, pooled together. In all cohorts, self-rated work ability was assessed at baseline (1978-80, 2000-2001 and 2017) using three response alternatives: completely fit (good work ability), partially disabled (limited work ability) and completely disabled (poor work ability) for work. PRIMARY AND SECONDARY OUTCOME MEASURES: All-cause mortality from national registers. Cox proportional hazards models were adjusted for socioeconomic characteristics, lifestyle factors, self-rated health and mental health problems. RESULTS: Of the participants, 2219 (13%) were classified as having limited and 991 (5.8%) poor work ability and 246 individuals died during the 4 year follow-up. The age- and sex-adjusted HR for mortality risk was 7.20 (95% CI 5.15 to 10.08) for participants with poor vs good work ability and 3.22 (95% CI 2.30 to 4.43) for participants with limited vs good work ability. The excess risk associated with poor work ability was seen in both genders, all age groups, across different educational levels, self-rated health levels and in those with and without mental health problems. The associations were robust to further adjustment for education, health behaviours, self-rated health and mental health problems. In the multivariable analyses, the HR for mortality among those with poor vs good work ability was 5.75 (95% CI 3.59 to 9.20). CONCLUSIONS: One-item poor self-rated work ability -measure is a strong predictor of increased risk of all-cause mortality and may be a useful survey-measure in predicting severe health outcomes in community-based surveys.Peer reviewe

Applicability of condensation particle counters to measure atmospheric clusters

This study presents an evaluation of a pulse height condensation particle counter (PH-CPC) and an expansion condensation particle counter (E-CPC) in terms of measuring ambient and laboratory-generated molecular and ion clusters. Ambient molecular cluster concentrations were measured with both instruments as they were deployed in conjunction with an ion spectrometer and other aerosol instruments in Hyytiälä, Finland at the SMEAR II station between 1 March and 30 June 2007. The observed cluster concentrations varied and ranged from some thousands to 100 000 cm -3. Both instruments showed similar (within a factor of ~5) concentrations. An average size of the detected clusters was approximately 1.8 nm. As the atmospheric measurement of sub 2-nm particles and molecular clusters is a challenging task, we conclude that most likely we were unable to detect the smallest clusters. Nevertheless, the reported concentrations are the best estimates to date for minimum cluster concentrations in a boreal forest environment

Geological Reconnaissance along the Alaska Highway from Fort Nelson, British Columbia, to Watson Lake, Yukon:

by M. Y. Williams.Paper (Geological Survey of Canada) ; 44-28