Yazar "Sessions, John" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim
    Öğe
    Planning Optimum Logging Operations through Precision Forestry Approaches
    (EJFE, 2015) Gülci, Neşe; Akay, Abdullah Emin; Erdaş, Orhan; Wing, Michael G.; Sessions, John
    In this study, it was aimed to determine optimum logging operations by using Geographical Information System (GIS) techniques as one of the effective tools of a precision forestry approach. In the first stage of the application process, a high resolution Digital Elevation Model (DEM) of the study area was produced by using Real Time Kinematic GPS in the field. Then, the DEM was used to classify the area into slope classes specified by the International Union of Forest Research Organizations (IUFRO). A map for the optimum logging operations was generated for two scenarios (i.e. maximum productivity and minimum residual stand damage) considering current terrain conditions. Four different logging methods were evaluated: ground skidding logs using a portable winch integrated with skidding cone, winching logs by using a farm tractor, downhill sliding of logs by chute system with gravity, and controlled sliding of logs downhill by chute system integrated with portable winch. During the assessment of logging methods, the results from the previous empirical studies conducted in similar stand characteristics and topographical conditions were used. For both scenarios, results indicated that skidding by portable winch integrated with skidding cone was the optimum logging method for more than half of the study area, followed by downhill sliding by chute system and controlled sliding by chute system integrated with portable winch.
  • Küçük Resim
    Öğe
    Productivity of a Portable Winch System Used in Salvage Logging of Storm-Damaged Timber
    (Zagreb Univ, Fac Forestry, 2019) Bilici, Ebru; Andiç, Güryay Volkan; Akay, Abdullah Emin; Sessions, John
    Storm damages result in serious losses in many regions, primarily by stem breakage or blow-down. Extraction of storm-damaged trees often requires more difficult than normal skidding activities due to obstacles created during the storm. In this study, the productivity of a portable winch was evaluated as a possible alternative to recover storm-damaged timber. Field measurements were conducted in the Alabarda Forest Enterprise Chief located near the city of Kutahya in western Turkey, where storm damage often occurs during the winter season. The time study was implemented in two slope classes (35% and 55%) and two skidding distances (40 m and 60 m). All timber was skidded uphill. A regression mode was developed that related productivity to log volume, ground slope and skidding distance. The highest percentage of total cycle time was observed for skidding logs to the landing. The highest productivity (3.96 m(3)/hour ) was found at the shorter skidding distance (40 m) and the lower ground slope (35%). Statistical analyses indicated that productivity was most highly affected by log volume, followed by skidding distance and ground slope. Larger log loads increased productivity, while both longer skidding distances and steeper slopes reduced productivity.