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Cloud condensation nuclei counter (CCNC) measurements performed at 14 locations around the world within the European Integrated project on Aerosol Cloud Climate and Air Quality interactions (EUCAARI) framework have been analysed and discussed with respect to the cloud condensation nuclei (CCN) activation and hygroscopic properties of the atmospheric aerosol. The annual mean ratio of activated cloud condensation nuclei (NCCN) to the total number concentration of particles (NCN), known as the activated fraction A, shows a similar functional dependence on supersaturation S at many locations – exceptions to this being certain marine locations, a free troposphere site and background sites in south-west Germany and northern Finland. The use of total number concentration of particles above 50 and 100 nm diameter when calculating the activated fractions (A50 and A100, respectively) renders a much more stable dependence of A on S; A50 and A100 also reveal the effect of the size distribution on CCN activation. With respect to chemical composition, it was found that the hygroscopicity of aerosol particles as a function of size differs among locations. The hygroscopicity parameter κ decreased with an increasing size at a continental site in south-west Germany and fluctuated without any particular size dependence across the observed size range in the remote tropical North Atlantic and rural central Hungary. At all other locations κ increased with size. In fact, in Hyytiälä, Vavihill, Jungfraujoch and Pallas the difference in hygroscopicity between Aitken and accumulation mode aerosol was statistically significant at the 5 % significance level. In a boreal environment the assumption of a size-independent κ can lead to a potentially substantial overestimation of NCCN at S levels above 0.6 %. The same is true for other locations where κ was found to increase with size. While detailed information about aerosol hygroscopicity can significantly improve the prediction of NCCN, total aerosol number concentration and aerosol size distribution remain more important parameters. The seasonal and diurnal patterns of CCN activation and hygroscopic properties vary among three long-term locations, highlighting the spatial and temporal variability of potential aerosol–cloud interactions in various environments., Atmospheric Chemistry and Physics, 15 (21), ISSN:1680-7375, ISSN:1680-7367

Article, Organic nitrates (ON) are known to be present in secondary organic aerosol and act as a reservoir of nitrogen oxides, regulating the local and regional ozone and hydroxyl radical budgets. This work reports observations of particulate ON in Finnish remote boreal forest at a site with dominant emissions from biogenic volatile organic compounds. High Resolution-Aerosol Mass Spectrometer data were analysed in a unique way to characterize the sources of inorganic and organic nitrates. ON were found to be related to local sources with semi-volatile properties. Also they were implying a nocturnal formation mechanism. Occasionally, local sawmill emissions contributed greatly to the organic nitrates. The observations indicated that in the remote boreal forest area the NO3 radicals are oxidizing biogenic VOCs producing ON. This work demonstrates the significant impact of anthropogenic-biogenic emissions interaction on the atmospheric organic nitrate aerosol mass concentration., published version, http://purl.org/eprint/status/PeerReviewed

This thesis was done for Metso Corporation as a part of RESPO project. RESPO is one of the ten projects in EFFIMA (Energy and Life Cycle Efficient Machines) research program. EFFIMA belongs to FIMECC’s (Finnish Metals and Engineering Competence Cluster) Intelligent Solutions (IS) strategic research theme. The purpose of task 2 in RESPO is to develop models and design principles into the development of software architecture. The goal of this thesis is to study the possibilities of applying software product line approach to rock crushing control system family. Several software-related problems have been recognized with the control system family. These include the long lifecycles and heterogeneity in the family. Another challenge is to manage variations in the family. The uncontrolled variations and heterogeneity prevent the effective reuse and increase the amount of extra work throughout the product lifecycle. The product line approach is applied to find solutions to the problems presented before. The approach in this thesis concentrates in the early development phase of the product line that includes addressing business, organizational, process and technological aspects. The variations in the current product family are modelled by scoping the requirements and the properties of control systems. The scoping is used to provide an understanding of the development trend in the business segment and thus to estimate future requirements. It is also used to provide better means for variation management in the product family. The scoping process and the variation modelling are used to create preliminary modernized product line architecture for next generation control systems. Less development and maintenance costs, shorter time-to-market, less errors, increased expandability, strategic reuse and easier product management are key incentives for the new architecture approach. To achieve these, the organization and its processes must be adapted and committed to the product line concept. In order to gain full benefits from the approach, the strengths and the weaknesses of both architecture and the product line itself need to be evaluated.