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Articles by Tuomas Nummelin

Category : Research article

article id 10385, category Research article
Perttu Anttila, Tuomas Nummelin, Kari Väätäinen, Juha Laitila. (2020). The effect of winter weather on timber truck tare weights. Silva Fennica vol. 54 no. 4 article id 10385. https://doi.org/10.14214/sf.10385
Keywords: forestry logistics; payload; tare weight; weather data
Highlights: In a one-year follow-up study of eight timber trucks in Finland, up to 6–12% increase in tare weights was observed in wintertime; Compared with summertime tare weights, the maximum increase varied between 1560 kg and 3100 kg; Potential payload loss was explained by temperature, relative humidity and precipitation.
Abstract | Full text in HTML | Full text in PDF | Author Info

In wintertime, the payload capacity of a timber truck is reduced by snow that accumulates on the structures of the truck. The aim of this study was to quantify the potential payload loss due to snow and winter accessories and to predict the loss with weather variables. Tare weights of eight timber trucks were collected at mill receptions in Finland over a one-year period. Monthly and annual loss of potential payload was estimated using the tare measurements in summer months as a reference. Each load was also connected with weather data at the location and time of delivery and payload loss explained by the weather data with the aid of regression models. The maximum loss of payload varied between 1560 kg and 3100 kg. On a monthly basis, the highest losses occurred in January, when the median values varied between 760 kg and 2180 kg. Over the year, the payload loss ranged between the trucks from 0.5% to 1.5% (from 1.9% and 5.1% in January) of the total number of loads in the study. Payload loss was found to increase with decreasing temperature, increasing relative humidity and increasing precipitation. Although the average payload loss was not very high, the biggest losses occur just during the season of highest capacity utilization. Big differences were also found in the tare weights between the trucks. The results of the study give incentive to develop truck and trailer structures that reduce the adherence of snow.

  • Anttila, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland ORCID https://orcid.org/0000-0002-6131-392X E-mail: perttu.anttila@luke.fi (email)
  • Nummelin, Natural Resources Institute Finland (Luke), Latokartanonkaari 9, FI-00790 Helsinki, Finland E-mail: tuomas.nummelin@luke.fi
  • Väätäinen, Natural Resources Institute Finland (Luke), Yliopistokatu 6, FI-80100 Joensuu, Finland E-mail: kari.vaatainen@luke.fi
  • Laitila, Natural Resources Institute Finland (Luke), Yliopistokatu 6, FI-80100 Joensuu, Finland ORCID https://orcid.org/0000-0003-4431-3319 E-mail: juha.laitila@luke.fi
article id 1394, category Research article
Sari Karvinen, Tuomas Nummelin. (2015). Finnish wood harvesting contractors’ risks in Russia. Silva Fennica vol. 49 no. 5 article id 1394. https://doi.org/10.14214/sf.1394
Keywords: Russia; contracting; wood harvesting; risk analysis
Highlights: Disagreements on wood measurement and payment delays were the most important economic risks; Dependency on a few clients created risk for unfavourable agreements and work interruptions; Fires in site huts caused the risk of personal injury; Inadequate professional skills were serious economic and work interruption risks; Unhealthy competition, the functioning of the authorities, and infrastructure were important external risk factors.
Abstract | Full text in HTML | Full text in PDF | Author Info

Finnish wood harvesting contractors have been working in Russia since the 1990s and new entrepreneurs are still interested in starting operations there, even though Russia is not an easy business environment. This study identifies the most significant risks in contracting in Russia. Risks were identified through expert evaluation and a risk analysis was conducted by using a risk matrix. Possible preventative measures were assessed for the identified risks. Some risks were found to be common in Russia and Finland, for example a limited number of clients, dependency on a few clients, and weak negotiating positions. A stable amount of work, i.e. the availability of stands for harvesting, was also a challenge on the both sides of border. Typical problems in Russia were breaches of contract, especially disagreements on wood measurement and payment delays, potentially causing serious economic losses. Specific to Russia were problems related to machine service and spare parts, as well as security issues. The professional skills of machine operators, as well as changing work motivation were risks in Russia. Cultural differences lead to more challenging supervision and management of staff. Among the external factors, the most challenging in Russia were unhealthy competition in the marketplace and non-transparent and the unpredictable procedures of the authorities. In Russia problems caused by seasonality are amplified by the sparse road network and longer downtime. The revealed specific features of the Russian business environment can help Finnish wood harvesting companies to plan a risk management process for operations in Russia.

  • Karvinen, Natural Resources Institute Finland (Luke), Economics and society, P.O. Box 68, FI-80101 Joensuu, Finland E-mail: sari.karvinen@luke.fi (email)
  • Nummelin, Natural Resources Institute Finland (Luke), Green technology, P.O. Box 18, FI-01301 Vantaa, Finland E-mail: tuomas.nummelin@luke.fi

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