http://hdl.handle.net/1957/7864 Collection contains recent scholarly output of student majors in the Department of Forest Engineering. Search the Channel search http://ir.library.oregonstate.edu/dspace/simple-search http://hdl.handle.net/1957/9503 Title: A model for the economic evaluation of training alternatives for complex logging tasks <br/> <br/>Abstract: Training of woodsworkers is described as important for the logging industry in Oregon. There has been little documentation of training gains or research that measures the effects of training from the perspective of the logging firm. Learning theories are evaluated and Towill's form of learning curves are selected for an experiment. A decision model is developed to assess the training gains in complex chokersetting tasks. Thirty subjects are matched and split into a control and experimental group based on initial task performance. Designed training is provided to the experimental group while the control group learns the way industry commonly performs training. Results are presented after six weeks of the experiment. Training gains are significant -- eighteen percent time savings in favor of the experimental group. Other statistical results were suggested by learning theory. Results of the experiment are incorporated and translated into the decision model developed. A simplified approach is described for logging firms. Simulation and sensitivity analysis are used to examine parameters of interest which include training gains, training costs, job change characteristics of workers, and recovery points of training costs. Summary discussions identify implementation obstacles and future research needs. <br/> <br/>Description: Graduation date: 1990 Thu, 03 May 1990 22:58:59 GMT http://hdl.handle.net/1957/9502 Title: Summertime stream temperatures in the North and South Forks of the Sprague River, south central Oregon <br/> <br/>Abstract: The Upper Sprague River Watershed (North and South Forks of the Sprague River) in south central Oregon provides important habitat for salmonid species, including native bull trout (Salvelinus confluentus) and redband trout (Oncorhynchus mykiss ssp.). Concern over the loss of viable habitat for these species has increased due to reductions in channel and habitat complexity, and modification of riparian vegetation. Many of the factors affecting habitat quality also influence water temperature, which is an important habitat component of salmonids during the summer months. Maximum stream temperatures and diel fluctuations in the Upper Sprague River System generally reflected local reach characteristics, position in the drainage, and large scale changes in valley shape. Stream temperatures in the North Fork Sprague River (NFSR), at a distance of 35 km from the drainage divide, equalled or exceeded 15°C, the 'upper preferred temperature' for salmonids, 16% and 36% of the time during the seven-consecutive warmest days of 1993 and 1994, respectively. Upstream of Lee Thomas Meadow (LTM), 6.5 km from the drainage divide, 15°C was equalled or exceeded only 1% and 13% of the time during the same period, while below LTM (18.3 km from the drainage divide), 15°C was exceeded 66% and 85% of the time during this sante period. Diel fluctuations in the NFSR were greatest immediately below LTM (>11.8°C), decreasing to <6.0°C below the canyon section at the mouth of the watershed during both 1993 and 1994. In the South Fork Sprague River (SFSR), 15°C was equalled or exceeded 79% and 99% of the time during the seven-consecutive warmest days of 1993 and 1994, respectively, 28.4 km from the divide. At this same distance, the upper lethal limit of 25°C was equalled or exceeded 16% of the time in 1994, representing very stressful or potentially life-threatening conditions for salmonids. Diel fluctuations for the SFSR were >6.5°C both years, the highest values being 9.5°C or greater at 28.4 kin from the divide. Seven-day maximum stream temperatures and diel fluctuations in tributaries of the Upper Sprague River System varied widely during the study period. Maximum stream temperatures varied from 13.8°C to 23.1°C while diel fluctuations varied from 4.8°C to 11.0°C; the highest values corresponding with relatively open, unshaded reaches and the lower values corresponding with shaded, forested reaches. Relationships between stream temperatures, stream cover and channel morphology characteristics were evaluated for eight reaches within the study area. Only stream cover was found to be significantly (p <0.05) related to seven-day maximum stream temperatures, change in stream temperatures, and diurnal fluctuations in stream temperatures based on simple linear regression. When multiple linear regression analysis was used, several combinations of independent variables were found to be significantly (p <0.05) related to seven-day maximum stream temperatures, and/or change in stream temperatures, and/or diurnal fluctuations in stream temperatures. The variables that were consistently part of significant (p <0.05) regressions included: stream cover, wetted width, thalweg depth, width/depth ratio, and reach length. A stream temperature model, SHADOW, was found to be a relatively good predictor of maximum stream temperatures for short (1130 m) reaches and generally a poor predictor for longer (1340-4130 m) reaches. For the three short reaches (1130 m), the average difference between observed and modelled temperatures was 0°C (±0.3°C); for the five longer reaches (1340-4130 m), the average difference was 2.9°C (±0.6°C) indicating that the SHADOW Model over-predicted stream temperatures for these longer reaches. The shortest forested reach was under-predicted by 0.4°C. Temperature simulations for five meadow reaches using SHADOW and multiple regression models suggest that lower maximum stream temperatures would be observed if stream cover were increased. <br/> <br/>Description: Graduation date: 1997; Presentation date: 1996-12-23 Sun, 22 Dec 1996 22:58:59 GMT http://hdl.handle.net/1957/9501 Title: Seasonal relationships between dissolved nitrogen and landuse/landcover and soil drainage at multiple spatial scales in the Calapooia Watershed, Oregon <br/> <br/>Abstract: The Calapooia River, a major tributary of the Willamette River in western Oregon, is a watershed typical of many found in the Willamette Basin. Public and private forested lands occur in the steep Upper Zone of the watershed, mixed forest and agriculture lands are found in the Middle Zone, and the Lower Zone of the watershed is comprised primarily of grass seed agriculture on relatively flat topography with poorly drained soils. High levels of dissolved nitrogen (DN) have been identified as a water-quality concern within the Calapooia River. To gain a better understanding of the relationship between landuse/landcover (LULC), soil drainage, and DN dynamics within the watershed on a seasonal basis, we selected 44 sub-basins ranging in size between 3 and 33 km² for monthly synoptic surface water-quality sampling from October 2003 through September 2004. We selected an additional 31 sample locations along the length of the Calapooia River to determine relative influence of the 44 sub-basins on DN concentrations in the river. T-tests were used to analyze differences between zones (Upper, Middle and Lower) and regression analysis was used to determine relationships between DN and LULC or soil drainage class. The agriculture-dominated sub-basins had significantly higher (< 0.05) DN concentrations than the predominantly forested sub-basins. Winter concentrations of nitrate-N were 43 times higher in agriculturally dominated sub-basins than in forested sub-basins, whereas in the spring, the difference was only 7-fold. High DN concentrations associated with the predominantly agriculture sub-basins were substantially reduced once they mixed with water in the Calapooia River, highlighting the likelihood that water draining the relatively nutrient-poor, forested sub-basins from the Upper Zone of the watershed, was diluting DN-rich water from the agriculture sub-basins. Relationships between DN and agriculture, woody vegetation or poorly drained soils were moderate to strong (0.50 < R² > 0.85) during the winter, spring and summer seasons. Results indicated an exponential increase in DN concentration when proportion agriculture or poorly drained soils increased, whereas an increase in woody vegetation was related to an exponential decrease in DN concentration. The high variability in DN concentration in the agriculture-dominated sub-basins suggests factors in addition to LULC and poorly drained soils influence DN in surface water. Seasonal relationships were developed between DN and proportion of poorly drained soils, agriculture, and woody vegetation at differing scales (10 m, 20 m, 30 m, 60 m, 90 m, 150 m, 300 m, and entire sub-basin), which we defined as Influence Zones (IZs), surrounding the stream network. Correlations between DN and proportion LULC or poorly drained soil at each IZ were analyzed for significant differences (p-value < 0.05) using the Hotelling-Williams test. Our results show strong seasonal correlations (r > 0.80) between DN and proportion of woody vegetation or agriculture, and moderate-to-strong seasonal correlations (r > 0.60) between DN and proportion of sub-basins with poorly drained soils. Altering scale of analysis significantly changed correlations between LULC and DN, with IZs < 150 m generally having higher correlations than the sub-basin level. In contrast, DN correlations with poorly drained soil were generally higher at the sub-basin scale than the 60- through 10-m IZs during winter and spring. These results indicate that scale of analysis is an important factor when determining relationships between DN concentration and proportion LULC or poorly drained soils. Furthermore, seasonal shifts in significant differences among IZs for correlations between LULC and DN suggest land management proximity and its influence on DN concentration changes temporally. DN relationships with poorly drained soil suggest that during winter and spring, when rainfall is highest, sub-basin scale soil drainage properties have a greater influence on DN than soil properties within IZs in close proximity to the stream network. <br/> <br/>Description: Graduation date: 2006 Sun, 19 Jun 2005 22:58:59 GMT http://hdl.handle.net/1957/9500 Title: Logging with a hydraulic excavator : a case study <br/> <br/>Abstract: This paper presents a production study of a modified hydraulic excavator used for yarding and loading logs. The machine utilized in this study is a Caterpillar 245. Approximately 3067 cunits (4053 pieces) of old growth Douglas fir were logged from a 29 acre setting in the Coast Range of southwestern Oregon. The purpose of the study is to develop and present important information concerning the application of a logging technique that is generating increasing interest from the forest industry in the Pacific Northwest. This purpose is accomplished by, 1) identifying the conditions affecting production, 2) providing a description of operating techniques, and 3) providing a preliminary investigation of soil impacts. Time study and regression techniques are used to develop equations for predicting yarding production. Significant independent variables include piece size, ground slope, and yarding distance. The relationships between production and piece size and yarding distance are nonlinear. On relatively flat ground the machine travels in a serpentine pattern, methodically swinging logs closer to the road on each pass. On steeper ground slopes (>30%), the terrain may preclude adherence to this otherwise efficient pattern; here the operator uses several techniques to increase the effective reach of the machine. A preliminary investigation of soil impacts indicated that off road soil compaction was not a significant problem; a 2 percent decrease in seedling height growth on 5 percent of the area. The high road density (7 percent of area) appeared to be the main impact on site quality. Mitigation measures could include tillage of the road surface and sidecast pull-back. The actual yarding production rate on the setting was 54.47 cunits/scheduled yarding hour. The yarding cost was $2.02/cunit. Total cost including road construction within the setting and loading was $9.61/cunit. The regression equation overpredicted actual cunit/hour production by 5 percent. <br/> <br/>Description: Graduation date: 1987; Presentation date: 1986-10-01 Sun, 28 Sep 1986 22:58:59 GMT