1. School of Forest Sciences, University of Eastern Finland, Joensuu, Finland
2. Department of Forestry and Forest Economics, Faculty of Natural Resources, University of Tehran, Karaj, Iran
3. Department of Forest Sciences, University of Helsinki, Helsinki, Finland
4. VTT Technical Research Centre of Finland, Espoo, Finland
5. Department of Electronics and Nanoengineering, School of Electrical Engineering, Aalto University, Helsinki, Finland