The Experts below are selected from a list of 43623 Experts worldwide ranked by ideXlab platform
Kris Welkenhuysen - One of the best experts on this subject based on the ideXlab platform.
-
Economic Threshold of co2 eor and co2 storage in the north sea a case study of the claymore scott and buzzard oil fields
International Journal of Greenhouse Gas Control, 2018Co-Authors: Kris Welkenhuysen, Bruno Meyvis, Rudy Swennen, Kris PiessensAbstract:Abstract CO2-enhanced oil recovery in the North Sea can provide additional oil revenues, prolong the productive lifetime of oil fields, and potentially catalyse the large-scale deployment of CO2 geological storage. Under the current low oil prices, around and below 50 €/bbl, the investment is more difficult to justify. Here we show three case studies for the Claymore, Scott and Buzzard fields offshore of Scotland. A techno-Economic assessment is made with the PSS IV simulator considering a low oil price scenario, market uncertainties and geological uncertainty. Stochastic parameters and project flexibility are used to simulate realistic project decisions. The Modified Internal Rate of Return (MIRR) is introduced as a performance indicator in combination with hurdle rate scenarios of 10, 11 and 12% for risk compensation. The possibility of continuing the storage of CO2 after oil production has stopped is considered, and reservoir uncertainty is introduced as stochastic parameters defining the EOR production profile. In terms of total value and development probability, the Buzzard field has the highest potential for a successful CO2-EOR project in all of the simulated scenarios, followed by Claymore and Scott. When compensating for field size, the Buzzard field still has the highest value per barrel of additionally produced oil, but the Scott field has a higher efficiency compared to Claymore. With an increase of the hurdle rate, the probability on investment in CO2-EOR decreases, but the probability on a profitable project increases. It also becomes more likely that if an EOR project is started, it will be followed by a CO2 storage phase. A hurdle rate of 12% even completely offsets the financial risk under the simulated conditions.
Kris Piessens - One of the best experts on this subject based on the ideXlab platform.
-
Economic Threshold of co2 eor and co2 storage in the north sea a case study of the claymore scott and buzzard oil fields
International Journal of Greenhouse Gas Control, 2018Co-Authors: Kris Welkenhuysen, Bruno Meyvis, Rudy Swennen, Kris PiessensAbstract:Abstract CO2-enhanced oil recovery in the North Sea can provide additional oil revenues, prolong the productive lifetime of oil fields, and potentially catalyse the large-scale deployment of CO2 geological storage. Under the current low oil prices, around and below 50 €/bbl, the investment is more difficult to justify. Here we show three case studies for the Claymore, Scott and Buzzard fields offshore of Scotland. A techno-Economic assessment is made with the PSS IV simulator considering a low oil price scenario, market uncertainties and geological uncertainty. Stochastic parameters and project flexibility are used to simulate realistic project decisions. The Modified Internal Rate of Return (MIRR) is introduced as a performance indicator in combination with hurdle rate scenarios of 10, 11 and 12% for risk compensation. The possibility of continuing the storage of CO2 after oil production has stopped is considered, and reservoir uncertainty is introduced as stochastic parameters defining the EOR production profile. In terms of total value and development probability, the Buzzard field has the highest potential for a successful CO2-EOR project in all of the simulated scenarios, followed by Claymore and Scott. When compensating for field size, the Buzzard field still has the highest value per barrel of additionally produced oil, but the Scott field has a higher efficiency compared to Claymore. With an increase of the hurdle rate, the probability on investment in CO2-EOR decreases, but the probability on a profitable project increases. It also becomes more likely that if an EOR project is started, it will be followed by a CO2 storage phase. A hurdle rate of 12% even completely offsets the financial risk under the simulated conditions.
M.a. Rizzardi - One of the best experts on this subject based on the ideXlab platform.
-
Grain Yield Losses and Economic Threshold Level Of GR® F2 Volunteer Corn in Cultivated F1 Hybrid Corn
2019Co-Authors: C. Piasecki, M.a. RizzardiAbstract:ABSTRACT: Volunteer corn is competitive with cultivated corn and the degree of interference varies according to their density and origin. This study aimed to determine the grain yield losses of GR® F1 hybrid corn as a function of the interferences with GR® F2 volunteer corn densities from individual plants and clumps, and determine the of Economic Threshold (ET). Two experiments were carried out in the field in a randomized block design with four replications and eight volunteer corn densities between 0 and 12 individual plants or clumps m-2. Each clump consisted of seven corn plants adhered to a piece of the rachis in the same point. The rectangular hyperbola model fitted to the percentage of grain yield losses of corn, generating the parameters for determining ET, which was calculated as a function of cost (US$ ha-1) and efficiency (%) of corn control, the price paid for corn (US$ kg-1), and corn grain yield (kg ha-1). Grain yield losses ranged from 2.7% to 34% for densities of 0.5 and 12 individual plants m-2 and 6.1% to 42% for 0.5 and 12 clumps m-2, respectively. The joint analysis of the results of experiments showed that from density of 2 m2 clumps are more competitive than individual plants and causes higher yield losses on cultivated corn. The average ET was 0.44 individual plants m-2 and 0.19 clumps m-2. However, from these densities, the control should be performed. Increases in corn grain yield and price paid, higher corn control efficiency, and a decrease in control costs promote a reduction in ET of volunteer corn in corn.
-
Yield Losses and Economic Threshold of GR® F2 Volunteer Corn in Bean
2018Co-Authors: C. Piasecki, M.a. RizzardiAbstract:ABSTRACT: Volunteer corn has high competitive capacity with bean, and the degree of interference varies as a function of corn density and origin (individual plant or clump). This study aimed to quantify bean yield losses under interference with densities of individual plants and clumps (seven plants at the same point) of GR® F2 volunteer corn and calculate the Economic Threshold (ET). Two experiments were carried out in a randomized blocks design with three replicates in Passo Fundo, RS, Brazil. The studied volunteer corn densities were 0, 0.5, 1, 2, 4, 8, and 12 individual plants and clumps m-2. The bean yield was assessed and calculated the yield losses (%) in response to volunteer corn interference. The yield loss data were fitted to the rectangular hyperbola model to generate the parameters for ET determining. ET was calculated as a function of cost (US$ ha-1) and control efficiency (%) of volunteer corn, the price paid for bean (US$ kg-1), and bean yield (kg ha-1). Interferences caused by densities of volunteer corn of 0.5, 1, and 2 individual plants and clumps m-2 in bean resulted in yield losses of 9%, 17%, and 30%, and 33%, 51%, and 70%, respectively. The ET of volunteer corn on bean was, on average, 0.21 individual plants m-2 and 0.04 clumps m-2. Increases in yield and price paid for beans, higher efficiency of volunteer corn control, and a decrease in costs of control promote a reduction in ET. Interferences caused by clumps resulted in higher bean yield losses than individual plants.
-
Economic Threshold of Volunteer Corn GR® in Soybean as a Function of Emergence Time and Origin of Corn
2018Co-Authors: C. Piasecki, M.a. RizzardiAbstract:ABSTRACT: Volunteer corn is extremely competitive with soybean and the degree of interference varies with the corn density, time of emergence and origin. The objectives of this work were to determine the Economic Threshold (ET) of volunteer corn GR® F2 in soybean as a function of the time of emergence (same day and nine days after soybean) and origin (individual plants or clumps). Each clump was manually adjusted to have seven corn plants. Four field experiments were conducted in randomized blocks design with four replicates in Passo Fundo, RS, Brazil. The soybean yield losses (%) were calculated and adjusted to the model of the rectangular hyperbola and generated the parameters for the determination of the ET, that was calculated based on the volunteer corn control costs (US$ ha-1), efficiency of control (%), price paid for soybean (US$ kg-1) and soybean yield (kg ha-1). The ET mean was 0.3 and 0.48 for individual corn plants m-2 emerged together and nine days after soybean, and 0.08 and 0.03 m-2 for individual plants and clumps, respectively. Increases in grain yield and price paid for soybean, greater control efficiency of corn and lower control cost promote reduction in the ET of volunteer corn in soybean. The control of volunteer corn is justified in a density less than 0.5 individual plant m-2 and is close to zero when corn originates from clumps. Volunteer corn is one of the most competitive weed in soybean crops.
Lin Wang - One of the best experts on this subject based on the ideXlab platform.
-
equilibrium pseudoequilibrium and sliding mode heteroclinic orbit in a filippov type plant disease model
Nonlinear Analysis-real World Applications, 2016Co-Authors: Jiafu Wang, Fengqin Zhang, Lin WangAbstract:Abstract Plant diseases have caused tremendous crop losses and have massive impacts on food security and environment. Modeling the spread of plant diseases and understanding the dynamics of the resulting plant disease models may provide practical insights on designing effective control measures. In this paper, by incorporating cultural strategies and Economic Threshold policy, we present a Filippov-type plant disease model. The resulting model has state dependent discontinuous right-hand side and thus non-smooth analysis and generalized Lyapunov approach are employed for model analysis. We show that the model exhibits the phenomena of stable equilibrium, unstable pseudoequilibrium as well as sliding-mode heteroclinic orbit. Biological implications of our results in implementing control strategies for plant diseases are also discussed.
Scott M. Swinton - One of the best experts on this subject based on the ideXlab platform.
-
probability of cost effective management of soybean aphid hemiptera aphididae in north america
Journal of Economic Entomology, 2009Co-Authors: Kevin D Johnson, Matthew E Oneal, Chris Difonzo, Erin W Hodgson, Philip M. Dixon, Bruce D Potter, David W. Ragsdale, Scott M. Swinton, Alejandro C CostamagnaAbstract:ABSTRACT Soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is one of the most damaging pests of soybean, Glycine max (L.) Merrill, in the midwestern United States and Canada. We compared three soybean aphid management techniques in three midwestern states (Iowa, Michigan, and Minnesota) for a 3-yr period (2005–2007). Management techniques included an untreated control, an insecticidal seed treatment, an insecticide fungicide tank-mix applied at flowering (i.e., a prophylactic treatment), and an integrated pest management (IPM) treatment (i.e., an insecticide applied based on a weekly scouting and an Economic Threshold). In 2005 and 2007, multiple locations experienced aphid population levels that exceeded the Economic Threshold, resulting in the application of the IPM treatment. Regardless of the timing of the application, all insecticide treatments reduced aphid populations compared with the untreated, and all treatments protected yield as compared with the untreated. Treatment efficacy and...
-
probability of cost effective management of soybean aphid hemiptera aphididae in north america
Journal of Economic Entomology, 2009Co-Authors: Kevin D Johnson, Matthew E Oneal, Chris Difonzo, Erin W Hodgson, Philip M. Dixon, Bruce D Potter, David W. Ragsdale, Scott M. Swinton, Alejandro C CostamagnaAbstract:Soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is one of the most damaging pests of soybean, Glycine max (L.) Merrill, in the midwestern United States and Canada. We compared three soybean aphid management techniques in three midwestern states (Iowa, Michigan, and Minnesota) for a 3-yr period (2005-2007). Management techniques included an untreated control, an insecticidal seed treatment, an insecticide fungicide tank-mix applied at flowering (i.e., a prophylactic treatment), and an integrated pest management (IPM) treatment (i.e., an insecticide applied based on a weekly scouting and an Economic Threshold). In 2005 and 2007, multiple locations experienced aphid population levels that exceeded the Economic Threshold, resulting in the application of the IPM treatment. Regardless of the timing of the application, all insecticide treatments reduced aphid populations compared with the untreated, and all treatments protected yield as compared with the untreated. Treatment efficacy and cost data were combined to compute the probability of a positive Economic return. The IPM treatment had the highest probability of cost effectiveness, compared with the prophylactic tank-mix of fungicide and insecticide. The probability of surpassing the gain Threshold was highest in the IPM treatment, regardless of the scouting cost assigned to the treatment (ranging from $0.00 to $19.76/ha). Our study further confirms that a single insecticide application can enhance the profitability of soybean production at risk of a soybean aphid outbreak if used within an IPM based system.
-
incorporating natural enemies in an Economic Threshold for dynamically optimal pest management
Ecological Modelling, 2009Co-Authors: Wei Zhang, Scott M. SwintonAbstract:The control of pests by their natural enemies represents an important regulating ecosystem service that helps maintain the stability of crop ecosystems. These services, however, are often ignored in pest management decision making. In addition, the use of broad-spectrum insecticides can damage the populations of natural enemies, reducing the cost-effectiveness of insecticide investment if unaccounted for in treatment decisions. The existing literature on modeling of biological control of insect pests has generally focused on simulations of the population dynamics of pest and natural enemy species and the processes underlying pest control. But agriculture is a managed ecosystem where predator–prey relationships are heavily influenced by human managers. In modeling managerial choices, this study develops an intra-seasonal dynamic bioEconomic optimization model for insecticide-based pest management that explicitly takes into account both the biological control effect of natural enemies on pest density and the nontarget mortality effect of insecticides on the level of natural pest control supplied. The model captures predator–prey interactions, linking them to crop growth and yield damage functions, which in turn are evaluated in a dynamic optimization framework. We introduce a new decision rule for judicious insecticide decisions using a natural enemy-adjusted Economic Threshold. This Threshold represents the pest population density at which insecticide control becomes optimal in spite of the opportunity cost of injury to natural enemies of the target pest. Using field data from Michigan, the model is applied to the case of soybean aphid (Aphis glycines, Matsumura), a recent invasive pest of soybean (Glycine max), whose management is of both Economic and environmental importance to the North Central region of the United States. As illustrated by the numerical examples, such natural enemy-adjusted Threshold is likely to lead to fewer recommendations for insecticide use than naive models that ignore natural enemies, resulting in less insecticide use, while maintaining profitability for farmers that rely on chemical pest control methods. The bioEconomic model developed in this study can be used to conduct a wide variety of analyses such as identifying dynamically optimal spray strategies and estimating the implied Economic value of natural control services. Furthermore, with the incorporation of inter-year carry-over factors, such as overwintering of pests and natural enemies, the current model can contribute to building multi-year models for studying long-term pest management.
