scholarly journals Harvendusraiete tasuvuse analüüs ja pikaajalise mõju simulatsioonid Järvselja õppe- ja katsemetskonnas

2020 ◽  
Vol 72 (1) ◽  
pp. 54-63
Author(s):  
Paavo Kaimre ◽  
Priit Vellak ◽  
Meelis Teder
Keyword(s):  
Forest Management ◽  
Net Present Value ◽  
Net Income ◽  
Wood Production ◽  
Present Value ◽  
Management Scenarios ◽  
Fuel Wood ◽  
Stand Management ◽  
Long Run ◽  
The Impact

AbstractThe results of the analysis of profitability and impact of thinning on wood production in Järvselja Training and Experimental Forest Centre are presented in the article. The profitability was assessed on the basis of harvesting income and costs of logging operations in 2015–2017. The impact of thinning on the wood production was assessed using the MOTTI simulation program. Three different scenarios for the management of the stand were compared: 1) stand management in accordance with the Finnish forest management recommendations (Tapio recommendations), 2) management according to the Estonian Forest Management Regulations and 3) stand development without thinning. The results revealed that 61 thinnings out of the 70 were profitable. The average net income from thinning was 344 euros per hectare. Fuel wood accounted for 45% and pulpwood for 30% of the harvested timber. Net present value was applied as a criterion to assess the profitability of long-term management scenarios. Considering Tapio's recommendations, the total net present value was 33% higher and following Estonian forest management rules, it was 23% higher compared to the simulations without thinning. The results indicated that thinning is economically viable in the long run. In simulations without thinning, timber production is the highest, but the net present value of management is lower compared to simulations with thinning.

A dynamic programming algorithm for optimization of uneven-aged forest stands

1994 ◽  
Vol 24 (9) ◽  
pp. 1758-1765 ◽  
Author(s):  
David J. Anderson ◽  
B. Bruce Bare
Keyword(s):  
Dynamic Programming ◽  
Interest Rates ◽  
Net Present Value ◽  
Initial Conditions ◽  
Dynamic Programming Algorithm ◽  
Basal Area ◽  
Management Problem ◽  
Present Value ◽  
Stand Management ◽  
The Impact

A deterministic dynamic programming formulation of the transition uneven-aged stand management problem is presented. Using a previously published northern hardwoods growth model, a forward recursive, discrete, two-state problem that maximizes the net present value of harvested trees at each stage is developed. State variables represent the total number of trees and the total basal area per acre. A neighborhood storage concept previously published is used to reduce the number of states considered at each stage. Two harvest allocation rules are used to assign the harvested basal area to individual diameter classes. Terminal end point conditions and stage to stage sustainability are not required. Results from four base runs of the model are presented and compared with previously published results. Each run produces significantly different optimal paths, with one showing a higher net present value than any previously published. Sensitivity runs illustrate the impact of changes in interest rates, width of neighborhood storage class, and initial conditions. Dynamic programming offers promise for analyzing uneven-aged stand management problems.

scholarly journals Using Naturalness for Assessing the Impact of Forestry and Protection on the Quality of Ecosystems in Life Cycle Assessment

2021 ◽  
Vol 13 (16) ◽  
pp. 8859
Author(s):  
Sylvie Côté ◽  
Robert Beauregard ◽  
Manuele Margni ◽  
Louis Bélanger
Keyword(s):  
Life Cycle Assessment ◽  
Species Richness ◽  
Life Cycle ◽  
Forest Management ◽  
Black Spruce ◽  
Management Strategies ◽  
Assessment Model ◽  
Wood Production ◽  
Management Scenarios ◽  
The Impact

A novel approach is proposed to evaluate the impact of forestry on ecosystem quality in life cycle assessment (LCA) combining a naturalness assessment model with a species richness relationship. The approach is applied to a case study evaluating different forest management strategies involving concomitantly silvicultural scenarios (plantation only, careful logging only or the current mix of both) combined with an increasing share of protected area for wood production in a Québec black spruce forest. The naturalness index is useful to compare forest management scenarios and can help evaluate conservation needs considering the type of management foreseen for wood production. The results indicate that it is preferable to intensify forest management over a small proportion of the forest territory while ensuring strict protection over the remaining portion, compared to extensive forest management over most of the forested area. To explore naturalness introduction in LCA, a provisory curve relating the naturalness index (NI) with the potential disappeared fraction of species (PDF) was developed using species richness data from the literature. LCA impact scores in PDF for producing 1 m3 of wood might lead to consistent results with the naturalness index but the uncertainty is high while the window leading to consistent results is narrow.

scholarly journals Gas to Liquids Techno-Economics of Associated Natural Gas, Bio Gas, and Landfill Gas

Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1568
Author(s):  
Federico Galli ◽  
Jun-Jie Lai ◽  
Jacopo De Tommaso ◽  
Gianluca Pauletto ◽  
Gregory S. Patience
Keyword(s):  
Natural Gas ◽  
Net Present Value ◽  
Landfill Gas ◽  
Labor Cost ◽  
Variable Cost ◽  
Selling Price ◽  
Present Value ◽  
Fischer Tropsch ◽  
Gas To Liquids ◽  
The Impact

Methane is the second highest contributor to the greenhouse effect. Its global warming potential is 37 times that of CO2. Flaring-associated natural gas from remote oil reservoirs is currently the only economical alternative. Gas-to-liquid (GtL) technologies first convert natural gas into syngas, then it into liquids such as methanol, Fischer–Tropsch fuels or dimethyl ether. However, studies on the influence of feedstock composition are sparse, which also poses technical design challenges. Here, we examine the techno-economic analysis of a micro-refinery unit (MRU) that partially oxidizes methane-rich feedstocks and polymerizes the syngas formed via Fischer–Tropsch reaction. We consider three methane-containing waste gases: natural gas, biogas, and landfill gas. The FT fuel selling price is critical for the economy of the unit. A Monte Carlo simulation assesses the influence of the composition on the final product quantity as well as on the capital and operative expenses. The Aspen Plus simulation and Python calculate the net present value and payback time of the MRU for different price scenarios. The CO2 content in biogas and landfill gas limit the CO/H2 ratio to 1.3 and 0.9, respectively, which increases the olefins content of the final product. Compressors are the main source of capital cost while the labor cost represents 20–25% of the variable cost. An analysis of the impact of the plant dimension demonstrated that the higher number represents a favorable business model for this unit. A minimal production of 7,300,000 kg y−1 is required for MRU to have a positive net present value after 10 years when natural gas is the feedstock.

scholarly journals An Analysis of the Effectiveness of Two Rainwater Harvesting Systems Located in Central Eastern Europe

Water ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 458 ◽  
Author(s):  
Agnieszka Stec ◽  
Martina Zeleňáková
Keyword(s):  
Sensitivity Analysis ◽  
Net Present Value ◽  
Rainwater Harvesting ◽  
Payback Period ◽  
Practical Aspect ◽  
Financial Ratios ◽  
Present Value ◽  
Toilet Flushing ◽  
Harvesting Systems ◽  
The Impact

Decentralized water systems are perceived as solutions that not only save water, but also as a way to partially or completely become independent from centralized suppliers. Taking this into account, an analysis of the effectiveness of rainwater harvesting systems (RWHS) for toilet flushing in existing academic facilities located in Poland and in Slovakia was carried out. The tests took into account the different volumes of storage tanks collecting rainwater. On the basis of two financial ratios, namely Net Present Value and Discounted Payback Period, the profitability of these systems was also assessed. The research was extended by the sensitivity analysis, which allowed determination of the impact of changes in individual cost components on the financial effectiveness of the investments considered. The results obtained clearly showed that the implementation of RWHS in the dormitory in Rzeszów was unprofitable for all tank capacities tested, and the payback period significantly exceeded the period of 30 years accepted for the analysis. Completely different results were obtained for RWHS in a dormitory located in the city of Košice, for which the financial ratios NPV (Net Present Value) and DPP (Discounted Payback Period) were very favorable. It was also confirmed by the results of the sensitivity analysis. The use of rainwater for toilet flushing caused that it was possible to achieve water savings of an average of 29% and 18%, respectively, for facilities located in Slovakia and Poland. The results of the research have a practical aspect and can provide an indication for potential investors and managers of academic facilities, similar to those analyzed in the article. Taking into account that in many countries water and sewage rates are significantly higher than in Poland and Slovakia, the cost-effectiveness of using the analyzed installation options in these countries could be even higher.

Improvement in Operational Efficiency Due to ERP Systems Implementation

2011 ◽  
pp. 43-61 ◽  
Author(s):  
Vijay K. Vemuri ◽  
Shailendra C. Palvia
Keyword(s):  
Return On Investment ◽  
Market Value ◽  
Operational Efficiency ◽  
Net Income ◽  
Erp Systems ◽  
Present Value ◽  
Systems Implementation ◽  
Business Efficiency ◽  
The Impact ◽  
Direct Measures

ERP systems are expected to provide many benefits, including improved business efficiency. However, they are also blamed for several business problems and failures. Past studies have analyzed investments in ERP systems based on net income, return on investment, new present value or change in market value of a firm. We argue that an analysis of more direct measures—intangible or tangible—would enhance confidence in the efficacy of ERP systems. We investigate the impact of ERP systems implementation on operational efficiency of medium sized firms in the pharmaceutical and chemicals industry. Our analysis of the data indicates that for a majority of the firms improvement of operational performance expected due to ERP systems did not materialize.

scholarly journals Assessment of the Nutritional Impact of Agricultural Research: The Case of Mungbean in Pakistan

2005 ◽  
Vol 26 (3) ◽  
pp. 287-294 ◽  
Author(s):  
Katinka Weinberger
Keyword(s):  
Net Present Value ◽  
Agricultural Research ◽  
Low Cost ◽  
Secondary Data ◽  
Marginal Effect ◽  
Micronutrient Deficiencies ◽  
Iron Intake ◽  
Present Value ◽  
Piece Rate ◽  
The Impact

Background Evaluation of agricultural research often neglects consumption and nutrition aspects. Yet agricultural research can address micronutrient malnutrition by improving both quantity and quality of food intake. Objective To briefly review the conceptual linkages between agriculture and nutrition, to estimate the strength of the relationship between iron intake and productivity outcomes, and to estimate the nutritional benefit of improved mungbean varieties in terms of net present value. This paper presents a methodology for assessing the nutritional impact of mungbean, and summarizes current impact evidence on the path from mungbean research to consumption. Methods A consumption study was conducted among female piece-rate workers in Pakistan to analyze the impact of iron consumption on productivity, measured in wages. A two-stage least-squares analysis was used to estimate the elasticity of iron intake on wages. The results derived from this study were extrapolated to country level using secondary data sources. Results We found that anemia among women was widespread. Approximately two-thirds of women suffered from mild or severe anemia (Hb < 12 g/dL). We found the elasticity of bioavailable iron on productivity measured in wages was 0.056, and the marginal effect was 9.17 Pakistani rupees per additional mg of bioavailable iron consumed. Using the model results we estimated the impact of mungbean research on nutrition, in terms of productivity effects, and found it was substantial, ranging from US$7.6 to 10.1 million cumulative present value (in 1995 US$ at 5% discount rate). Conclusions Agriculture certainly plays an important role in the reduction of malnutrition. Agricultural research has greatly contributed to the reduction of hunger and starvation by providing millions of hungry people with access to low-cost staple foods. Now, as the challenge shifts to the reduction of micronutrient deficiencies, more efforts must be directed toward crops high in micronutrients, such as pulses and vegetables.

SYLVER: Modelling the Impact of Silviculture on Yield, Lumber Value, and Economic Return

1988 ◽  
Vol 64 (2) ◽  
pp. 127-131 ◽  
Author(s):  
Kenneth J. Mitchell
Keyword(s):  
Net Present Value ◽  
Financial Analysis ◽  
Wood Properties ◽  
Growth And Yield ◽  
Present Value ◽  
Silvicultural Treatments ◽  
Intensive Forest Management ◽  
Product Value ◽  
Analysis System ◽  
The Impact

Intensive forest management requires an understanding of the effect that silvicultural treatments have on wood properties, standing yield, log quality, product value, and net present value. These needs are addressed by a system of models (SYLVER) which includes the Tree and Stand Simulator (TASS), Root Rot Simulator (ROTSIM), Sawmill Simulator (SAWSIM), and the new Financial Analysis System (FAN$Y). The latter will be used by field foresters to compare the merits of candidate treatments for specific stands. Key words: Silviculture, growth and yield, juvenile wood, log quality, end-product value, net present value, Pseudotsuga menziesii, Phellinus weirii, modelling, TASS, ROTSIM, SAWSIM, FAN$Y, SYLVER.

The Impact of China’s Passenger Turnover Quantity on Farmer Income Increase

2014 ◽  
Vol 1065-1069 ◽  
pp. 3301-3305
Author(s):  
Cong Zhang
Keyword(s):  
Positive Influence ◽  
Rank Test ◽  
Net Income ◽  
The Road ◽  
Peasant Workers ◽  
Long Run ◽  
Equilibrium Relationship ◽  
Causality Tests ◽  
Per Capita ◽  
The Impact

Based on the data of passenger turnover quantity, agriculture gross production, peasant workers’ salary and rural per capita net income from 1973 to 2013 of China, this paper empirically analyzed the impact of China’s passenger person-kilometers on rural per capita net income. By build Var model, Co-integration Rank Test and Granger Causality Tests, author illustrate the relation between passenger person-kilometers and rural per capita net income. The results show that there are one way lead relations and long-run equilibrium relationship between them. The increase of person-kilometers has positive influence on rural per capita net income. We can promote the farmers' income by strengthen the construction of rural roads and planning the road network more reasonable.

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