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  • Laitakari, Erkki (Suomen metsätieteellinen seura, 1961)
  • Jukola-Sulonen, Eeva-Liisa; Salemaa, Maija (Suomen metsätieteellinen seura, 1985)
  • Westman, Carl Johan; Starr, Michael; Laine, Jukka (Suomen metsätieteellinen seura, 1985)
  • Peng, Shikui (Suomen metsätieteellinen seura, 1986)
  • Schabenberger, Oliver; Gregoire, Timothy G. (The Finnish Society of Forest Science and The Finnish Forest Research Institute, 1995)
    Much of forestry data is characterized by a longitudinal or repeated measures structure where multiple observations taken on some units of interest are correlated. Such dependencies are often ignored in favor of an apparently simpler analysis at the cost of invalid inferences. The last decade has brought to light many new statistical techniques that enable one to successfully deal with dependent observations. Although apparently distinct at first, the theory of Estimating Functions provides a natural extension of classical estimation that encompasses many ot these new approaches. This contribution introduces Estimating Function Theory as a principle with potential for unification and presents examples covering a variety of modeling issues to demonstrate its applicability.
  • Kuusipalo, Jussi; Niemensivu, Helena; Berg, Mari-Anna; Mikkola, Marja (Suomen metsätieteellinen seura, 1989)
  • Kangas, Jyrki; Pukkala, Timo (Suomen metsätieteellinen seura, 1992)
  • Toppinen, Anne; Laaksonen, Susanna; Hänninen, Riitta (The Finnish Society of Forest Science and The Finnish Forest Research Institute, 1996)
    This study investigates the relationship between Finnish sulphate pulp export prices and international pulp inventories using the Johansen cointegration method. Long-run equilibrium is found to exist between pulp price and NORSCAN inventory for the study period, 1980–94. Granger causality is found to exist from inventory to price but not vice versa. A simple short-run forecasting model for the Finnish pulp export price is formed. In preliminary analysis, the explanatory power of model is found to be acceptable but only under stable market conditions.
  • Hari, Pertti; Korpilahti, Eeva; Pohja, Toivo; Räsänen, Pentti K. (Suomen metsätieteellinen seura, 1990)
  • de Reffye, Philippe; Fourcaud, Thierry; Blaise, Frédéric; Barthélémy, Daniel; Houllier, François (The Finnish Society of Forest Science and The Finnish Forest Research Institute, 1997)
    A new approach for modelling plant growth using the software AMAPpara is presented. This software takes into consideration knowledge about plant architecture which has been accumulated at the Plant Modelling Unit of CIRAD for several years, and introduces physiological concepts in order to simulate the dynamic functioning of trees. The plant is considered as a serial connection of vegetative organs which conduct water from the roots to the leaves. Another simple description of the plant as a network of parallel pipes is also presented which allows an analytical formulation of growth to be written. This recurring formula is used for very simple architectures and is useful to understand the role of each organ in water transport and assimilate production. Growth simulations are presented which show the influence of modifications in architecture on plant development.
  • Tolvanen-Sikanen, Tiina; Sikanen, Lauri; Harstela, Pertti (The Finnish Society of Forest Science and The Finnish Forest Research Institute, 1995)
    The first aim of this study was to develop a simulation model describing the flow of different timber qualities to different firms. The second aim was to study preliminarily the factors which affect timber distributions. In addition, we tested the hypothesis that in a small sawmill firm the traditional way of organizing timber procurement does not direct effectively good quality logs to the special production. The game theoretic approaching and the principles of Monte-Carlo simulation were applied in developing of the simulation model. The most important factors of the model were tried to find for further studies with sensitive analyses. Empirical validation brought forth promising results in the area of one municipality. The buyer’s awareness of a marked stand, the seller’s willingness to sell a marked stand, the buyer’s ability to pay for wood and the proportion of first quality pine logs in a marked stand affected the distribution of pine logs. The results also supported the hypothesis that the traditional system, in which sawmills or their own forest department procure themselves all timber needed, is not the most effective way to direct enough good quality timber to the special production.
  • Blomqvist, A. G. (Suomen metsätieteellinen seura, 1959)
  • Nisula, Pentti (Suomen metsätieteellinen seura, 1963)
  • Heiskanen, Veijo (Suomen metsätieteellinen seura, 1964)
  • Yli-Vakkuri, Paavo (Suomen metsätieteellinen seura, 1954)
  • Hari, Pertti.; Kulmala, Markku.; Pohja, Toivo; Lahti, Tapani.; Siivola, Erkki.; Palva, Lauri; Aalto, Pasi; Hämeri, Kaarle; Vesala, Timo; Luoma, Sari.; Pulliainen, Erkki. (The Finnish Society of Forest Science and The Finnish Forest Research Institute, 1994)
    The Värriö environmental measurement station has been designed and constructed during 1991 and 1992. The measurement system consists of measurement units for gases (sulphur dioxide, ozone, carbon dioxide), particles, photosynthesis and irradiation. A meteorological station is also included. The preliminary measurement period was started on August, 1991. During the first year (1991–1992) some parts of the system were redeveloped and rebuilt. Full, continuous measurements started in August 1992. The system has been working quite reliably, with good accuracy. The preliminary results show that pollution episodes are observed when the wind direction is from Monchegorsk or Nikel, the main emission sources in Kola Peninsula.
  • Hämäläinen, Jouko (Suomen metsätieteellinen seura, 1989)
  • Valonen, Paavo (Suomen metsätieteellinen seura, 1977)
  • Laitakari, Erkki (Suomen metsätieteellinen seura, 1967)