Browsing by Subject "methods"

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  • Kankaanpää, Harri T.; Turja, Raisa; Lehtonen, Kari K. (Springer Science and Business Media LLC, 2022)
    Ambio
    Comment to: Kanwischer, M., N. Asker, A.S. Wernersson, M.A. Wirth, K. Fisch, E. Dahlgren, H. Osterholz, F. Habedank, et al. 2021. Substances of emerging concern in Baltic Sea water: Review on methodological advances for the environmental assessment and proposal for future monitoring. Ambio. https://doi.org/10.1007/s13280-021-01627-6
  • Hari, Pertti; Kanninen, Markku; Kellomäki, Seppo; Luukkanen, Olavi; Pelkonen, Paavo; Salminen, Raimo; Smolander, Heikki (Suomen metsätieteellinen seura, 1979)
  • Nyyssönen, Aarne (Suomen metsätieteellinen seura, 1963)
  • Hyvärinen, Heini; Skyttä, Annaliina; Jernberg, Susanna; Meissner, Kristian; Kuosa, Harri; Uusitalo, Laura (Springer, 2021)
    Environmental Monitoring and Assessment 193: 400
    Global deterioration of marine ecosystems, together with increasing pressure to use them, has created a demand for new, more efficient and cost-efficient monitoring tools that enable assessing changes in the status of marine ecosystems. However, demonstrating the cost-efficiency of a monitoring method is not straightforward as there are no generally applicable guidelines. Our study provides a systematic literature mapping of methods and criteria that have been proposed or used since the year 2000 to evaluate the cost-efficiency of marine monitoring methods. We aimed to investigate these methods but discovered that examples of actual cost-efficiency assessments in literature were rare, contradicting the prevalent use of the term “cost-efficiency.” We identified five different ways to compare the cost-efficiency of a marine monitoring method: (1) the cost–benefit ratio, (2) comparative studies based on an experiment, (3) comparative studies based on a literature review, (4) comparisons with other methods based on literature, and (5) subjective comparisons with other methods based on experience or intuition. Because of the observed high frequency of insufficient cost–benefit assessments, we strongly advise that more attention is paid to the coverage of both cost and efficiency parameters when evaluating the actual cost-efficiency of novel methods. Our results emphasize the need to improve the reliability and comparability of cost-efficiency assessments. We provide guidelines for future initiatives to develop a cost-efficiency assessment framework and suggestions for more unified cost-efficiency criteria.
  • Fridlund, Mats; Oiva, Mila; Paju, Petri (Helsinki University Press, 2020)
    Historical scholarship is currently undergoing a digital turn. All historians have experienced this change in one way or another, by writing on word processors, applying quantitative methods on digitalized source materials, or using internet resources and digital tools. Digital Histories showcases this emerging wave of digital history research. It presents work by historians who – on their own or through collaborations with e.g. information technology specialists – have uncovered new, empirical historical knowledge through digital and computational methods. The topics of the volume range from the medieval period to the present day, including various parts of Europe. The chapters apply an exemplary array of methods, such as digital metadata analysis, machine learning, network analysis, topic modelling, named entity recognition, collocation analysis, critical search, and text and data mining. The volume argues that digital history is entering a mature phase, digital history ‘in action’, where its focus is shifting from the building of resources towards the making of new historical knowledge. This also involves novel challenges that digital methods pose to historical research, including awareness of the pitfalls and limitations of the digital tools and the necessity of new forms of digital source criticisms. Through its combination of empirical, conceptual and contextual studies, Digital Histories is a timely and pioneering contribution taking stock of how digital research currently advances historical scholarship.
  • Myllys, M.; Henri, P.; Vallieres, X.; Gilet, N.; Nilsson, H.; Palmerio, E.; Turc, L.; Wellbrock, A.; Goldstein, R.; Witasse, O. (2021)
    Context. The Mutual Impedance Probe (RPC-MIP) carried by the Rosetta spacecraft monitored both the plasma density and the electric field in the close environment of comet 67P/Churyumov-Gerasimenko (67P), as the instrument was operating alternatively in two main modes: active and passive. The active mode is used primarily to perform plasma density measurements, while the passive mode enables the instrument to work as a wave analyzer. Aims. We are reporting electric field emissions at the plasma frequency near comet 67P observed by RPC-MIP passive mode. The electric field emissions are related to Langmuir waves within the cometary ionized environment. In addition, this study gives feedback on the density measurement capability of RPC-MIP in the presence of cold electrons. Methods. We studied the occurrence rate of the electric field emissions as well as their dependence on solar wind structures like stream interaction regions (SIRs) and coronal mass ejections (CMEs). Results. We are showing that strong electric field emissions at the plasma frequency near 67P were present sporadically throughout the period when Rosetta was escorting the comet, without being continuous, as the occurrence rate is reported to be of about 1% of all the measured RPC-MIP passive spectra showing strong electric field emissions. The Langmuir wave activity monitored by RPC-MIP showed measurable enhancements during SIR or CME interactions and near perihelion. Conclusions. According to our results, Langmuir waves are a common feature at 67P during the passage of SIRs. Comparing the plasma frequency given by the RPC-MIP passive mode during Langmuir wave periods with the RPC-MIP active mode observations, we conclude that the measurement accuracy of RPC-MIP depends on the operational submode when the cold electron component dominates the electron density.
  • Morasse, Johanne M. G. (The Society of Forestry in Finland - The Finnish Forest Research Institute, 1998)
    Two methods of pre-harvest inventory were designed and tested on three cutting sites containing a total of 197 500 m3 of wood. These sites were located on flat-ground boreal forests located in northwestern Quebec. Both methods studied involved scaling of trees harvested to clear the road path one year (or more) prior to harvest of adjacent cut-blocks. The first method (ROAD) considers the total road right-of-way volume divided by the total road area cleared. The resulting volume per hectare is then multiplied by the total cut-block area scheduled for harvest during the following year to obtain the total estimated cutting volume. The second method (STRATIFIED) also involves scaling of trees cleared from the road. However, in STRATIFIED, log scaling data are stratified by forest stand location. A volume per hectare is calculated for each stretch of road that crosses a single forest stand. This volume per hectare is then multiplied by the remaining area of the same forest stand scheduled for harvest one year later. The sum of all resulting estimated volumes per stand gives the total estimated cutting-volume for all cut-blocks adjacent to the studied road. A third method (MNR) was also used to estimate cut-volumes of the sites studied. This method represents the actual existing technique for estimating cutting volume in the province of Quebec. It involves summing the cut volume for all forest stands. The cut volume is estimated by multiplying the area of each stand by its estimated volume per hectare obtained from standard stock tables provided by the governement. The resulting total estimated volume per cut-block for all three methods was then compared with the actual measured cut-block volume (MEASURED). This analysis revealed a significant difference between MEASURED and MNR methods with the MNR volume estimate being 30 % higher than MEASURED. However, no significant difference from MEASURED was observed for volume estimates for the ROAD and STRATIFIED methods which respectively had estimated cutting volumes 19 % and 5 % lower than MEASURED. Thus the ROAD and STRATIFIED methods are good ways to estimate cut-block volumes after road right-of-way harvest for conditions similar to those examined in this study.
  • Nyyssönen, Aarne; Kilkki, Pekka (Suomen metsätieteellinen seura, 1966)
  • Euclid Collaboration; Ilić, S.; Aghanim, N.; Gozaliasl, G.; Keihänen, E.; Kirkpatrick , C. C.; Kurki-Suonio, H.; Lindholm, Valtteri; Väliviita, J. (2022)
    The combination and cross-correlation of the upcoming Euclid data with cosmic microwave background (CMB) measurements is a source of great expectation since it will provide the largest lever arm of epochs, ranging from recombination to structure formation across the entire past light cone. In this work, we present forecasts for the joint analysis of Euclid and CMB data on the cosmological parameters of the standard cosmological model and some of its extensions. This work expands and complements the recently published forecasts based on Euclid-specific probes, namely galaxy clustering, weak lensing, and their cross-correlation. With some assumptions on the specifications of current and future CMB experiments, the predicted constraints are obtained from both a standard Fisher formalism and a posterior-fitting approach based on actual CMB data. Compared to a Euclid-only analysis, the addition of CMB data leads to a substantial impact on constraints for all cosmological parameters of the standard ?-cold-dark-matter model, with improvements reaching up to a factor of ten. For the parameters of extended models, which include a redshift-dependent dark energy equation of state, non-zero curvature, and a phenomenological modification of gravity, improvements can be of the order of two to three, reaching higher than ten in some cases. The results highlight the crucial importance for cosmological constraints of the combination and cross-correlation of Euclid probes with CMB data.
  • Säily, Tanja; Mäkelä, Eetu; Hämäläinen, Mika (2018)
    This paper describes ongoing work towards a rich analysis of the social contexts of neologism use in historical corpora, in particular the Corpora of Early English Correspondence, with research questions concerning the innovators, meanings and diffusion of neologisms. To enable this kind of study, we are developing new processes, tools and ways of combining data from different sources, including the Oxford English Dictionary, the Historical Thesaurus, and contemporary published texts. Comparing neologism candidates across these sources is complicated by the large amount of spelling variation. To make the issues tractable, we start from case studies of individual suffixes (-ity, -er) and people (Thomas Twining). By developing tools aiding these studies, we build toward more general analyses. Our aim is to develop an open-source environment where information on neologism candidates is gathered from a variety of algorithms and sources, pooled, and presented to a human evaluator for verification and exploration.
  • Dawson, Samantha Katherine; Boddy, Lynne; Halbwachs, Hans; Bässler, Claus; Andrew, Carrie; Crowther, Thomas Ward; Heilmann-Clausen, Jacob; Nordén, Jenni; Ovaskainen, Otso; Jönsson, Mari (2019)
    Functional traits are widely recognized as a useful framework for testing mechanisms underlying species community assemblage patterns and ecosystem processes. Functional trait studies in the plant and animal literature have burgeoned in the past 20 years, highlighting a need for standardized ways to measure ecologically meaningful traits across taxa and ecosystems. However, standardized measurements of functional traits are lacking for many organisms and ecosystems, including fungi. Basidiomycete wood fungi occur in all forest ecosystems world-wide, where they are decomposers and also provide food or habitat for other species, or act as tree pathogens. Despite their major role in the functioning of forest ecosystems, the understanding and application of functional traits in studies of communities of wood fungi lags behind other disciplines. As the research field of fungal functional ecology is growing, there is a need for standardized ways to measure fungal traits within and across taxa and spatial scales. This handbook reviews pre-existing fungal trait measurements, proposes new core fungal traits, discusses trait ecology in fungi and highlights areas for future work on basidiomycete wood fungi. We propose standard and potential future methodologies for collecting traits to be used across studies, ensuring replicability and fostering between-study comparison. Combining concepts from fungal ecology and functional trait ecology, methodologies covered here can be related to fungal performance within a community and environmental setting. This manuscript is titled "a start with" as we only cover a subset of the fungal community here, with the aim of encouraging and facilitating the writing of handbooks for other members of the macrofungal community, for example, mycorrhizal fungi. A is available for this article.
  • Nevalainen, Terttu; Säily, Tanja; Vartiainen, Turo; Liimatta, Aatu; Lijffijt, Jefrey (2020)
    In this paper, we explore the rate of language change in the history of English. Our main focus is on detecting periods of accelerated change in Middle English (1150–1500), but we also compare the Middle English data with the Early Modern period (1500–1700) in order to establish a longer diachrony for the pace at which English has changed over time. Our study is based on a meta-analysis of existing corpus research, which is made available through a new linguistic resource, the Language Change Database (LCD). By aggregating the rates of 44 individual changes, we provide a critical assessment of how well the theory of punctuated equilibria (Dixon 1997) fits with our results. More specifically, by comparing the rate of language change with major language-external events, such as the Norman Conquest and the Black Death, we provide the first corpus-based meta-analysis of whether these events, which had significant societal consequences, also had an impact on the rate of language change. Our results indicate that major changes in the rate of linguistic change in the late medieval period could indeed be connected to the social and cultural after-effects of the Norman Conquest. We also make a methodological contribution to the field of English historical linguistics: by re-using data from existing research, linguists can start to ask new, fundamental questions about the ways in which language change progresses.
  • Lappalainen, Hanna (John Benjamins, 2019)
    This chapter proposes and evaluates new data collection methods that use visual material to analyze address practices. The methods are illustrated by two experiments. The first experiment used photographs as part of Discourse Completion Tasks for exploring self-reported uses of address forms in service encounters in Helsinki and Tallinn. The second experiment, which simulates an encounter with a celebrity, was conducted using life-size photographs in a Finnish shopping center. While such test data cannot replace authentic discourse as reported use does not necessarily match actual use, the two data sources can complement each other. Using visual material also attracts respondents who might not be accessed by traditional data collection methods such as interviews and questionnaires.
  • Gozaliasl, G.; Finoguenov, A.; Khosroshahi, H. G.; Laigle, C.; Kirkpatrick, C. C.; Kiiveri, K.; Devriendt, J.; Dubois, Y.; Ahoranta, J. (2020)
    In an effort to better understand the formation of galaxy groups, we examine the kinematics of a large sample of spectroscopically confirmed X-ray galaxy groups in the Cosmic Evolution Survey with a high sampling of galaxy group members up to z & x2004;=& x2004;1. We compare our results with predictions from the cosmological hydrodynamical simulation of HORIZON-AGN. Using a phase-space analysis of dynamics of groups with halo masses of M-200c & x2004;similar to & x2004;10(12.6) - 10(14.50)& x2006;M-circle dot, we show that the brightest group galaxies (BGG) in low mass galaxy groups (M-200c & x2004;<& x2004;2 x 10(13)& x2006;M-circle dot) have larger proper motions relative to the group velocity dispersion than high mass groups. The dispersion in the ratio of the BGG proper velocity to the velocity dispersion of the group, sigma(BGG)/sigma(group), is on average 1.48 +/- 0.13 for low mass groups and 1.01 +/- 0.09 for high mass groups. A comparative analysis of the HORIZON-AGN simulation reveals a similar increase in the spread of peculiar velocities of BGGs with decreasing group mass, though consistency in the amplitude, shape, and mode of the BGG peculiar velocity distribution is only achieved for high mass groups. The groups hosting a BGG with a large peculiar velocity are more likely to be offset from the L-x - sigma(v) relation; this is probably because the peculiar motion of the BGG is influenced by the accretion of new members.
  • Nissinen, Ari; Seppälä, Jyri; Heinonen, Tero (Elsevier Ltd., 2022)
    Cleaner logistics and supply chain
    The carbon footprint (CF) should finally have a role in the decision-making of manufacturing companies, retailers, public procurers and consumers. We consider that more systematic approaches are urgently needed for collecting, storing and presenting carbon footprint information. The key issue from the standpoint of reliability and comparability is to recognise how each CF was determined and how it has been verified. Global Trade Item Number (GTIN) and the connected barcode symbol can be used to identify products. We propose that the presented framework can help to build databases which are easy to use for the manufacturers, retailers and various service providers and which can increase the production and usability of CF information.
  • Keskitalo, Jorma; Salonen, Kalevi (National Board of Waters and the Environment, 1994)
    Publications of the Water and Environment Administration - Series B 16
  • Säily, Tanja; Nurmi, Arja; Sairio, Anni (John Benjamins, 2018)
    Advances in Historical Sociolinguistics
  • Nyyssönen, Aarne; Kilkki, Pekka; Mikkola, Erkki (Suomen metsätieteellinen seura, 1967)
  • Kiczko, Adam; Västilä, Kaisa; Kozioł, Adam; Kubrak, Janusz; Kubrak, Elzbieta; Krukowski, Marcin (EGU, 2020)
    Hydrology and Earth System Sciences 24 8 (2020)
    Despite the development of advanced process-based methods for estimating the discharge capacity of vegetated river channels, most of the practical one-dimensional modeling is based on a relatively simple divided channel method (DCM) with the Manning flow resistance formula. This study is motivated by the need to improve the reliability of modeling in practical applications while acknowledging the limitations on the availability of data on vegetation properties and related parameters required by the process-based methods. We investigate whether the advanced methods can be applied to modeling of vegetated compound channels by identifying the missing characteristics as parameters through the formulation of an inverse problem. Six models of channel discharge capacity are compared in respect of their uncertainty using a probabilistic approach. The model with the lowest estimated uncertainty in explaining differences between computed and observed values is considered the most favorable. Calculations were performed for flume and field settings varying in floodplain vegetation submergence, density, and flexibility, and in hydraulic conditions. The output uncertainty, estimated on the basis of a Bayes approach, was analyzed for a varying number of observation points, demonstrating the significance of the parameter equifinality. The results showed that very reliable predictions with low uncertainties can be obtained for process-based methods with a large number of parameters. The equifinality affects the parameter identification but not the uncertainty of a model. The best performance for sparse, emergent, rigid vegetation was obtained with the Mertens method and for dense, flexible vegetation with a simplified two-layer method, while a generalized two-layer model with a description of the plant flexibility was the most universally applicable to different vegetative conditions. In many cases, the Manning-based DCM performed satisfactorily but could not be reliably extrapolated to higher flows.