scholarly journals Evaluating productivity, cost, chip quality and biomass recovery for a mobile chipper in Australian roadside chipping operations

2012 ◽  
Vol 58 (No. 12) ◽  
pp. 530-535 ◽  
Author(s):  
M.R. Ghaffariyan ◽  
J. Sessions ◽  
M. Brown
Keyword(s):  
Energy Consumption ◽  
Average Cost ◽  
Biomass Yield ◽  
Energy Content ◽  
Time Study ◽  
Pine Plantation ◽  
Productivity Cost ◽  
System Productivity ◽  
Chip Quality ◽  
Biomass Recovery

The Bruks mobile chipper was tested for chipping extracted non-merchantable stemwood at the roadside in Pine plantation in Victoria. The elemental time study method was used to evaluate the system productivity. The productivity, cost, biomass yield, remaining slash, chip quality (size classification and energy content), and fuel and energy consumption were analysed. Chipping extracted small logs at the roadside yielded a productivity of 43.88 GMt&middot;PMH<sub>0</sub><sup>&ndash;1</sup> (19.4 BDT&middot;PMH<sub>0</sub><sup>&ndash;1</sup>). The average cost was about 16.96 USD&middot;GMt<sup>&ndash;1</sup> (38.36 USD&middot;BDT<sup>&ndash;1</sup>).

scholarly journals Insight into the Productivity, Cost and Soil Impacts of Cable-assisted Harvester-forwarder Thinning in Western Oregon

2019 ◽  
Vol 66 (1) ◽  
pp. 82-96 ◽  
Author(s):  
Preston Q Green ◽  
Woodam Chung ◽  
Ben Leshchinsky ◽  
Francisca Belart ◽  
John Sessions ◽  
...  
Keyword(s):  
Pacific Northwest ◽  
Soil Compaction ◽  
The United States ◽  
Soil Conditions ◽  
Productivity Cost ◽  
System Productivity ◽  
Machine Productivity ◽  
Before And After ◽  
Harvesting Systems ◽  
Soil Measurements

Abstract Cable-assisted (or tethered) mechanized harvesting has recently been introduced to the Pacific Northwest of the United States, and is rapidly being adopted by the forest industry. However, potential environmental impacts, productivity and cost of the new harvesting systems have not been well-assessed. This study aims to examine the effects of cable assistance on soil compaction, system productivity and cost through a field-based experiment. A harvester-forwarder system was used to thin a harvest unit on dry soils in western Oregon, with and without cable-assistance. We conducted a detailed time study during operations and collected soil measurements before and after machine passes. Machine productivity ranged from 28.75 to 92.36 m3 per scheduled machine hour, with resulting unit costs for untethered and tethered systems ranging from $13.19 to $18.13/m3. Our results showed reduced soil impacts in both extent and degree of soil compaction when cable assistance was employed. The reduced extent of soil impacts is attributed to a reduction in track wander owing to the operative tensions of the tether cable, and the smaller increase in soil density appears to be attributed to combined effects of initially denser soil conditions and reduced shear displacement as a result of cable-assistance.

scholarly journals The effect of partial automation on the productivity and cost of a mobile tower yarder

2020 ◽  
Vol 63 (2) ◽  
pp. 3-14
Author(s):  
Raffaele Spinelli ◽  
Rien Visser ◽  
Natascia Magagnotti ◽  
Carolina Lombardini
Keyword(s):  
Cost Effective ◽  
Automated System ◽  
Eastern Region ◽  
Productivity Cost ◽  
System Productivity ◽  
Human Factors And Ergonomics ◽  
Integration Of Technology ◽  
Levels Of Automation ◽  
Cable Yarding ◽  
The Difference

t Integration of technology is commonplace in forestry equipment supporting higher levels of automation and efficiency. For technology adoption to be successful it must demonstrate improvement in productivity, cost–effectiveness or in human factors and ergonomics. Cable yarding lends itself to automation with repetitive machine movement along a fixed corridor, as established by the skyline. This study aimed at investigating the difference in productivity between the two possible settings (manual and automated) of a Valentini V850 yarder equipped with automatic path programming, with a Bergwald 3-t carriage and radio controlled chokers. The study took place in the northern Italian Alpine eastern region over a period of 8 days on two separate corridors, resulting in 280 measured cycles split between manual and automated. Results in terms of absolute numbers were very close for the two system options, but significant differences were found. For example, inhaul time was longer, but outhaul time shorter for the automated system. Productivity ranged from 8.2 to 13.3 m3 PMH-1, and cost from approximately 20 to 30 € m-3. The automated system did achieve a significantly higher productivity, but differences declined with extraction distance. When that was combined with the slightly higher cost for the automated system, the automated system was more cost-effective on extraction distances less than 200 m, and the manual system on longer distances.

Impaired Energy Metabolism in Platelets from Patients with Wiskott-Aldrich Syndrome

1989 ◽  
Vol 61 (01) ◽  
pp. 010-014 ◽  
Author(s):  
Adrie J M Verhoeven ◽  
Irene E A van Oostrum ◽  
Hans van Haarlem ◽  
Jan-Willem N Akkerman
Keyword(s):  
Energy Consumption ◽  
Energy Content ◽  
Energy Charge ◽  
Energy Generation ◽  
Adenylate Energy Charge ◽  
Atp Production ◽  
Wiskott Aldrich Syndrome ◽  
Transport Chain ◽  
Function Defect ◽  
Impaired Energy Metabolism

SummaryThe platelet function defect seen in patients with Wiskott- Aldrich syndrome (WAS) has been ascribed to abnormal mitochondrial energy generation. The present study reveals a reduced energy content and low adenylate energy charge in platelets from two WAS-patients. Energy consumption in the resting platelets is slightly beyond the normal range, especially when ATP-resynthesis is primarily glycolytic. When platelets are stimulated with thrombin, the increase in energy consumption is 40-60% lower than in controls, both when energy is produced in glycolysis as when the mitochondria supply most of the energy. Analysis of the electron transport chain reveals no abnormalities. In contrast, the balance between glycolytic and mitochondrial ATP resynthesis is disturbed with a lowered contribution of oxidative ATP production. No such abnormalities are found in two WAS-carriers with the exception of a slight impairment in energy consumption during stimulation with thrombin. Thus, the platelet malfunction in WAS may be caused by a defect in the regulation of energy generation.

INFLUENCE OF DIETARY FAT ON ENERGY CONSUMPTION AND DIGESTION AND ON NITROGEN UTILIZATION OF WEANLING RATS

1958 ◽  
Vol 38 (2) ◽  
pp. 187-193 ◽  
Author(s):  
J. P. Bowland ◽  
R. T. Berg ◽  
I. R. Sibbald ◽  
N. Hussar
Keyword(s):  
Energy Consumption ◽  
Corn Oil ◽  
Energy Content ◽  
Nitrogen Retention ◽  
Albino Rats ◽  
Food Utilization ◽  
Sprague Dawley ◽  
Digestible Energy ◽  
Nitrogen Levels ◽  
Acclimatization Period

Energy digestibility and nitrogen retention were determined with weanling albino rats of the Sprague-Dawley strain fed diets varying from 0 to 30 per cent corn oil and containing 3 ratios of Cal. apparent digestible energy per gm. apparent digestible nitrogen at each fat level. Vitamins, salts and pure linoleic acid were included in the diets at calculated constant levels relative to the apparent digestible energy content. A 7-day metabolism, period followed a 7-day diet acclimatization period. Food consumption varied inversely with the digestible energy content of the diet so that intake of digestible Cal. remained essentially constant and gain in weight of the rats was similar at all fat levels. Nitrogen levels per se did not influence digestible energy consumption but an interaction existed between fat × nitrogen levels in the diet in relation to digestible energy intake. Efficiency of food utilization improved as either fat or nitrogen levels in the diet increased. Energy digestibility was decreased slightly by the addition of fat to a fat-free diet when allowance was made for the influence of non-nutritive cellulose levels in the diets. The addition of fat to the diet resulted in a significant improvement in nitrogen digestibility and gross nitrogen retention.

Weighed Plate Waste Can Accurately Measure Children's Energy Consumption from Food in Quick-Service Restaurants

2019 ◽  
Author(s):  
Julie E Gervis ◽  
Erin Hennessy ◽  
Eleanor T Shonkoff ◽  
Peter Bakun ◽  
Juliana Cohen ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Energy Content ◽  
Slight Variation ◽  
Bomb Calorimetry ◽  
Plate Waste ◽  
Energy Assessment ◽  
Feasible Option ◽  
Gross Energy ◽  
Mean Differences ◽  
Quick Service

ABSTRACT Background Quick-service restaurants (QSRs) serve one-third of US children on any given day, yet no methods can directly measure energy (kcal) consumed in QSRs. Weighed plate waste is one feasible option, but the accuracy is unknown. Objective The objective of this study was to determine the accuracy of weighed plate waste for measuring children's energy consumption in QSRs. Methods Children's plate waste (entrées and sides) was collected for a larger study assessing a community-wide health messaging campaign to inform parents’ orders for children in QSRs; a subsample (n = 194) was used for validation. Gross energy left over estimated by weighed plate waste combined with restaurant-stated nutrition information was compared to gross energy determined by bomb calorimetry, the gold-standard energy assessment technique. Analyses were conducted at the meal level (all food items, combined) and stratified by the number of items per meal (1, 2, or 3). Pearson correlations and paired t tests analyzed agreement; Bland-Altman statistics examined differences between energy estimations for the total and stratified subsample. Results Overall, significant agreement was observed between weighed plate waste and bomb calorimetry (r = 0.99, P < 0.001). On average, weighed plate waste underestimated energy content by <2 kcal compared with bomb calorimetry (mean percent difference ± SD of 0.3% ± 10.7%); 94% of estimations fell within the limits of agreement (−23.5 to 26.8 kcal), and 63% and 24% of estimations differed by <10 or <20 net kcal, respectively. Although stratification by item number showed slight variation, mean differences for all strata were <5 kcal (t test P > 0.80), suggesting the accuracy of weighed plate waste for measuring meals of various sizes. Conclusions Weighed plate waste is an accurate and valid field technique for measuring children's energy consumption from food in QSRs. Future improvements to capturing beverages, self-serve condiments, and sharing behaviors may improve the overall feasibility and accuracy.

scholarly journals Energy, Economic, and Environmental Assessment of Coriander Seed Production Using Material Flow Cost Accounting and Life Cycle Assessment

2021 ◽  
Author(s):  
Majid Dekamin ◽  
Kamran Kheiralipour ◽  
Reza Keshavarz Afshar
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Energy Consumption ◽  
Seed Production ◽  
Material Flow ◽  
Cost Accounting ◽  
Environmental Indicators ◽  
World Population ◽  
System Productivity ◽  
Coriander Seed

Abstract The agricultural sector in the world is facing social expectations to reduce energy consumption and environmental impacts; and at the same producing enough food and fiber for the growing world population. The purpose of the present research to determine the economic, energy consumption, and environmental indicators in coriander seed production using novel approach of material flow cost accounting (MFCA) along with classical life cycle assessment (LCA). The positive output and negative energy were 25485 and 6742 MJ ha−1, respectively. Energy efficiency, net energy gain, specific energy, and energy productivity indicators were calculated as 0.6, -11944 MJ ha−1, 17.4 MJ kg−1, and 0.06 kg MJ−1, respectively. The average production cost was calculated as 588 $ ha−1 (334 $ ton−1) whereas gross income was 1267 $ ha−1 (720 $ ton−1). The value of negative products in coriander production was estimated as 239 $ ha−1 (136 $ ton−1). Seed shedding at harvest and water loss due to inefficient irrigation system were found to be the major negative products (economic and energy) in the system that can enhance the system productivity upon improvement. The values of benefit costs ratio and economic productivity were 1.74 and 3 kg $−1, respectively. The acidification potential (58.2 kg SO2 eq ton−1), global warming potential (510 kg CO2 eq ton−1), photochemical oxidation potential (0.13 kg C2H4 eq ton−1), and eutrophication potential (23 kg PO4 −3 eq ton−1) indicators were evaluated. The hotspots in point of economic (labor and seed shedding), energy use (nitrogen fertilizer and machinery) and energy loss (seed shedding), and environment (diesel fuel consumption) were determined which can be used to optimize coriander production through decreasing the material and energy consumption in the field. The results showed that MFCA combined with LCA is a powerful tool in identifying hotspots in crop production systems and can be used in developing more sustainable systems as well as in developing sustainability models.

EFFECT OF STEAM PELLETING ON THE PERFORMANCE OF HENS FED VARIOUS LAYING DIETS

1968 ◽  
Vol 48 (2) ◽  
pp. 229-234 ◽  
Author(s):  
W. F. Pepper ◽  
J. D. Summers ◽  
S. J. Slinger ◽  
G. C. Ashton
Keyword(s):  
Energy Consumption ◽  
Wheat Bran ◽  
Soybean Meal ◽  
Egg Production ◽  
Energy Content ◽  
The Body ◽  
The Other ◽  
Steam Treatment ◽  
Production Type ◽  
Body Weights

Egg production-type pullets were fed either corn–soybean meal, wheat–soybean meal, or corn–soy rations containing 15 or 30% of wheat bran or shorts. All diets were fed both in the form of mash and as steamed crumbles. Steam treatment of the corn–soy diet resulted in egg production that was poorer than with a similar diet fed in mash form, and also inferior to that with most of the other experimental rations. In an overall comparison, the mash diets resulted in significantly more eggs per bird than did the steam-crumbled rations.In general, birds fed crumbled rations consumed more feed and gained more weight than those fed mash rations. The increase in energy consumption with the crumbled feed was apparently in excess of requirements and was consequently laid down as fat in the body, as suggested by the increased body weights. It seems evident that the energy content of diets for caged layers should be lower when crumbled feed is provided than when mash is used.The wheat-shorts diets fed in the form of mash resulted in higher production than did the bran diets fed in mash form. However, when these diets were fed as steamed crumbles there was no signficant difference between the shorts and bran rations.

Productivity and Cost Changes in Southern Pulpwood Harvesting, 1979 to 1987

1994 ◽  
Vol 18 (2) ◽  
pp. 83-90 ◽  
Author(s):  
Frederick Cubbage ◽  
Douglas Carter
Keyword(s):  
Average Cost ◽  
Southern Pine ◽  
System Productivity ◽  
Unit Costs ◽  
Harvesting Systems ◽  
Harvesting Costs

Abstract Analyses of southern pine pulpwood harvesting systems indicate that substantial increases in productivity and decreases in per unit costs occurred from 1979 to 1987. Average shortwood harvesting production increased from 34 cords per week in 1979 to 42 cords per week in 1987; average longwood system productivity increased from 191 cords per week in 1979 to 227 cords per week in 1987. Estimated shortwood average costs were $45.50 per cord in 1979 and increased to $48.90 per cord in constant 1988 (real) dollars. Average real longwood harvesting costs decreased from $34.00 per cord in 1979 to $26.50 per cord in 1987. Most productivity improvements and average cost declines overall were attributable to increased use of longwood harvesting systems. South. J. Appl. For. 18(2):83-90.

scholarly journals Optimization of anaerobic co-digestion of sewage sludge using bio-chemical substrates

2018 ◽  
Author(s):  
◽  
Nhlanganiso Ivan Madondo
Keyword(s):  
Sewage Sludge ◽  
Energy Content ◽  
Oxygen Demand ◽  
Methane Yield ◽  
Batch Experiment ◽  
Batch Test ◽  
System Productivity ◽  
Biogas Yield ◽  
Volatile Solids ◽  
Substrate To Inoculum Ratio

The anaerobic process is increasingly becoming a subject for many as it reduces greenhouse gas emissions and recovers carbon dioxide energy as methane. Even though these benefits are attainable, proper control and design of the process variables has to be done in order to optimize the system productivity and improve stability. The aim of this research was to optimize methane and biogas yields on the anaerobic co-digestion of sewage sludge using bio-chemical substrates as co-substrates. The first objective was to find the bio-chemical substrate that will generate the highest biogas and methane yields. The anaerobic digestion of these substrates was operated using 6 L digesters at 37.5℃. The substrate which generated the highest biogas and methane yield in the first batch experiment was then used for the second batch test. The objective was to optimize the anaerobic conditions (substrate to inoculum ratio, co-substrate concentration and temperature) in-order to optimize the biogas and methane yields. The second batch test was achieved using the conventional One-Factor-At-A-Time (OFAT) and the Design of Experiment (DOE) methods. Final analysis showed that the bio-chemical substrates could be substrates of interest to biogas generators. Amongst the substrates tested in the first batch experiment glycerol (Oleo-Chemical Product waste) generated the highest methane and biogas yields of 0.71 and 0.93 L. (g volatile solids added)-1, respectively. It was believed that glycerol contains significant amount of other organic substances such as lipids that have higher energy content than the other bio-chemical substrates, thus generating larger biogas and methane yields. Moreover, digestion of sewage sludge alone produced biogas yields of 0.19 L /g VS and 0.33 L/g COD, and methane yields of 0.16 L/g VS and 0.28 L/g COD. Generally, co-digestion yields were higher than digestion yields of sewage alone. Using the OFAT method the results of the second batch test on glycerol demonstrated highest amounts of volatile solids (VS) reduction, chemical oxygen demand (COD) reduction, biogas yield and methane yield of 99.7%, 100%, 0.94 L (g VS added)-1 and 0.75 L (g VS added)-1 at a temperature, substrate to inoculum ratio and glycerol volume of 50℃, 1 (on VS basis) and 10 mL, respectively. Above 22 mL and substrate to inoculum ratio of 1, the process was inhibited. The DOE results suggested that the highest methane and biogas yields were 0.75 and 0.94 L (g VS added)-1, respectively. These results were similar to the OFAT results, thus the DOE software may be used to define the biogas and methane yields equations for glycerol. In conclusion, anaerobic co-digestion of bio-chemical substrates as co-substrates on sewage sludge was successfully applied to optimize methane and biogas yields.

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