Lidars for Wind Tunnels - an IRPWind Joint Experiment Project

Measurement campaigns with continuous-wave Doppler Lidars (Light detection and ranging) developed at DTU Wind Energy in Denmark were performed in two very different wind tunnels. Firstly, a measurement campaign in a small icing wind tunnel chamber at VTT in Finland was performed with high frequency measurements for increasing the understanding of the effect of in-cloud icing conditions on Lidar signal dynamics. Secondly, a measurement campaign in the relatively large boundary-layer wind tunnel at NTNU in Norway was performed in the wake of a scaled test turbine in the same configuration as previously used in blind test comparisons for wind turbine wake modelers. These Lidar measurement activities constitute the Joint Experiment Project” L4WT - Lidars for Wind Tunnels, with applications to wakes and atmospheric icing in a prospective Nordic Network” with the aim of gaining and sharing knowledge about possibilities and limitations with lidar instrumentation in wind tunnels, which was funded by the IRPWind project within the community of the European Energy Research Alliance (EERA) Joint Programme on Wind Energy

Residential wood combustion in Finland : PM2.5 emissions and health impacts with and without abatement measures

Exposure to fine particles in ambient air has been estimated to be one of the leading environmental health risks in Finland. Residential wood combustion is the largest domestic source of fine particles, and there is increasing political interest in finding feasible measures to reduce those emissions. In this paper, we present the PM2.5 emissions from residential wood combustion in Finland, as well as the resulting concentrations. We used population-weighed concentrations in a 250 × 250 m grid as population exposure estimates, with which we calculated the disease burden of the emissions. Compared to a projected baseline scenario, we studied the effect of chosen reduction measures in several abatement scenarios. In 2015, the resulting annual average concentrations were between 0.5 and 2 µg/m3 in the proximity of most cities, and disease burden attributable to residential wood combustion was estimated to be 3400 disability-adjusted life years (DALY) and 200 deaths. Disease burden decreased by 8% in the 2030 baseline scenario and by an additional 63% in the maximum feasible reduction scenario. Informational campaigns and improvement of the sauna stove stock were assessed to be the most feasible abatement measures to be implemented in national air quality policies

Influence of spatial resolution on population PM2.5 exposure and health impacts

Health effect estimates depend on the methods of evaluating exposures. Due to non-linearities in the exposure-response relationships, both the predicted mean exposures as well as its spatial variability are significant. The aim of this work is to systematically quantify the impact of the spatial resolution on population-weighted mean concentration (PWC), its variance, and mortality attributable to fine particulate matter (PM2.5) exposure in Finland in 2015. The atmospheric chemical transport model SILAM was used to estimate the ambient air PM2.5 concentrations at 0.02° longitudinal × 0.01° latitudinal resolution (ca. 1 km), including both the national PM2.5 emissions and the long-range transport. The decision-support model FRES source-receptor matrices applied at 250-m resolution was used to model the ambient air concentrations of primary fine particulate matter (PPM2.5) from local and regional sources up to 10 km and 20 km distances. Numerical averaging of population and concentrations was used to produce the results for coarser resolutions. Population-weighted PM2.5 concentration was 11% lower at a resolution of 50 km, compared with the corresponding computations at a resolution of 1 km. However, considering only the national emissions, the influences of spatial averaging were substantially larger. The average population-weighted local PPM2.5 concentration originated from Finnish sources was 70% lower at a resolution of 50 km, compared with the corresponding result obtained using a resolution of 250 m. The sensitivity to spatial averaging, between the finest 250-m and the coarsest 50-km resolution, was highest for the emissions of PPM2.5 originated from national vehicular traffic (about 80% decrease) and lowest for the national residential combustion (60% decrease). Exposure estimates in urban areas were more sensitive to the changes of model resolution (14% and 74% decrease for PM2.5 and local PPM2.5, respectively), compared with estimates in rural areas (2% decrease for PM2.5 and 36% decrease for PPM2.5). We conclude that for the evaluation of the health impacts of air pollution, the resolution of the model computations is an important factor, which can potentially influence the predicted health impacts by tens of percent or more, especially when assessing the impacts of national emissions

International benchmarking of terrestrial laser scanning approaches for forest inventories

The last two decades have witnessed increasing awareness of the potential of terrestrial laser scanning (TLS) in forest applications in both public and commercial sectors, along with tremendous research efforts and progress. It is time to inspect the achievements of and the remaining barriers to TLS-based forest investigations, so further research and application are clearly orientated in operational uses of TLS. In such context, the international TLS benchmarking project was launched in 2014 by the European Spatial Data Research Organization and coordinated by the Finnish Geospatial Research Institute. The main objectives of this benchmarking study are to evaluate the potential of applying TLS in characterizing forests, to clarify the strengths and the weaknesses of TLS as a measure of forest digitization, and to reveal the capability of recent algorithms for tree-attribute extraction. The project is designed to benchmark the TLS algorithms by processing identical TLS datasets for a standardized set of forest attribute criteria and by evaluating the results through a common procedure respecting reliable references. Benchmarking results reflect large variances in estimating accuracies, which were unveiled through the 18 compared algorithms and through the evaluation framework, i.e., forest complexity categories, TLS data acquisition approaches, tree attributes and evaluation procedures. The evaluation framework includes three new criteria proposed in this benchmarking and the algorithm performances are investigated through combining two or more criteria (e.g., the accuracy of the individual tree attributes are inspected in conjunction with plot-level completeness) in order to reveal algorithms’ overall performance. The results also reveal some best available forest attribute estimates at this time, which clarify the status quo of TLS-based forest investigations. Some results are well expected, while some are new, e.g., the variances of estimating accuracies between single-/multi-scan, the principle of the algorithm designs and the possibility of a computer outperforming human operation. With single-scan data, i.e., one hemispherical scan per plot, most of the recent algorithms are capable of achieving stem detection with approximately 75% completeness and 90% correctness in the easy forest stands (easy plots: 600 stems/ha, 20 cm mean DBH). The detection rate decreases when the stem density increases and the average DBH decreases, i.e., 60% completeness with 90% correctness (medium plots: 1000 stem/ha, 15 cm mean DBH) and 30% completeness with 90% correctness (difficult plots: 2000 stems/ha, 10 cm mean DBH). The application of the multi-scan approach, i.e., five scans per plot at the center and four quadrant angles, is more effective in complex stands, increasing the completeness to approximately 90% for medium plots and to approximately 70% for difficult plots, with almost 100% correctness. The results of this benchmarking also show that the TLS-based approaches can provide the estimates of the DBH and the stem curve at a 1–2 cm accuracy that are close to what is required in practical applications, e.g., national forest inventories (NFIs). In terms of algorithm development, a high level of automation is a commonly shared standard, but a bottleneck occurs at stem detection and tree height estimation, especially in multilayer and dense forest stands. The greatest challenge is that even with the multi-scan approach, it is still hard to completely and accurately record stems of all trees in a plot due to the occlusion effects of the trees and bushes in forests. Future development must address the redundant yet incomplete point clouds of forest sample plots and recognize trees more accurately and efficiently. It is worth noting that TLS currently provides the best quality terrestrial point clouds in comparison with all other technologies, meaning that all the benchmarks labeled in this paper can also serve as a reference for other terrestrial point clouds sources.</p

Konfigurointimalli yrityksen myynnin hallinnointi- ja kehitystyökaluna

Asiakaskohtaisesti räätälöitävien tuotteiden myyntimäärien hallinta ja tuotetietojen oikeellisuus ovat osoittautuneet haastaviksi tavoitteiksi räätälöitäviä tuotteita valmistavissa yrityksissä. Tämän työn tavoitteena oli selvittää, miten erikoistuotteiden suurta myyntiosuutta saataisiin hallittua paremmin ja miten myydyt tuotteet saataisiin paremmin vastaaman asiakkaan todellisia tarpeita. Erillisessä case -esimerkissä tutustutaan rullapihteihin ja luodaan rullapihdin konfigurointimalli myynnin tarpeisiin. Työn teoriaosassa esitettiin käsitteet massaräätälöinti, modulointi ja konfigurointi. Massaräätälöinnin keskeisin tavoite on valmistaa asiakaskohtaisesti räätälöityjä tuotteita kustannustehokkaasti ja nopeasti. Modulointi ja konfigurointi ovat massaräätälöinnin työkaluja, joiden avulla modulaarisesta tuoterakenteesta saadaan konfiguroitua eri tuoteperheiden variantteja. Lopuksi teoriaosuudessa esitettiin tarvittavat tiedot suunniteltavan työkalun eli konfigurointimallin luomiseksi. Myyntiosaston haastattelututkimuksen tavoite oli selvittää myyntiosaston mahdolliset puutteet ja heikkoudet, ottaa huomioon myynnin omat parannusehdotukset ja selvittää myynnin omat toiveet ja tarpeet suunniteltavan konfigurointimallin suhteen. Haastatteluista kävi ilmi, että asiakkaiden ja myyjien tarvittavien tuote- ja tavarankäsittelytietotaitojen ja työkalujen puute yhdistettynä suuriin ja epätäydellisiin tuotetietomääriin muodostivat ongelman ytimen. Haastatteluiden mukaan on olemassa selkeä tarve eri moduuleja yhdistelevälle työkalulle, jonka perusteella asiakkaan tarpeet voitaisiin konfiguroida suoraan tuotteen rakenneluetteloksi. Myös myyntiosaston toiminta- ja tiedonkeruutapoja on kehitettävä. Tarve selvittää asiakkaan todelliset tarpeet osoittautui erittäin tärkeäksi. Asiakkaan tarpeet muodostuivat asiakkaalle tutuista ja tunnetuista asioista kuten käsiteltävän tavaran, toimintaympäristön ja muiden liityntälaitteiden tiedoista. Vastuu myytävän laitteen teknisten spesifikaatioiden laadinnasta olisi siirrettävä rullapihdin myyjälle, ei asiakkaalle. Case esimerkissä tutustuttiin tarkemmin rullapihdin rakenteeseen ja ominaisuuksiin ja luotiin rullapihdin konfigurointimalli. Rullapihtituoteperheen moduulijakoon esitettiin joitain muutoksia, jotta tuotteen asiakastarpeiden mukainen konfigurointi tuotteiden rakenneluetteloksi helpottuisi. Suunniteltu konfigurointimalli pyrki poistamaan myyntitoiminnassa esiin tulleita ongelmakohtia ja samalla helpottamaan myyntiosaston työtehtäviä. Haastattelututkimuksessa selvitettyihin puutteisiin ja ongelmakohtiin sekä esitettyihin tutkimuskysymyksiin saatiin kelvollinen ratkaisu esitetyllä konfigurointimallilla, vaikkei esityskelpoista tietokoneohjelmistoa luotukaan. Lisäksi konfigurointimalliin saatiin otettua huomioon myyntiosaston toiveita, jotka lisäävät mahdollisen konfigurointimallin mukaisen ohjelmiston eli konfiguraattorin arvoa käyttöönottotilanteessa. Saatu konfigurointimalli pyrkii muuntamaan 'asiakkaan kielen yrityksen kielelle jolloin kaikki osapuolet voivat puhua samasta asiasta omilla termeillään ja tiedoillaan. Suunnitellulla konfigurointimallilla pyritään ennen kaikkea helposti ja tehokkaasti luomaan asiakastarpeita vastaavan tuotteen rakenneluettelo