Science.gov

Sample records for production economic models

  1. A Simple Economic Model of Cocaine Production

    DTIC Science & Technology

    1994-01-01

    the current state of the cocaine market that are used to parameterize the model. The results of a set of simulations of the model are then presented...and they lead to the following conclusions "Crop substitutionW programs will have a negligible impact on the world cocaine market . As desirable for...strategies that seize and destroy 70 percent or less of production, without limiting the total level of production, will have little impact on the market . If

  2. A Simple Economic Model of Cocaine Production

    DTIC Science & Technology

    1994-01-01

    insignificant; in fiscal year 1991 these programs received about $500 million, out of a total federal drug control budget of $10.6 billion. They have...been important, often dominant, in U.S. relationships with the Andean region and, at times, with Burma, Mexico , Pakistan, and Turkey. The effort to...control drug production overseas has generally been viewed as ineffective. Mexico , the most cooperative of the source countries, continues to produce

  3. Process model economics of xanthan production from confectionery industry wastewaters.

    PubMed

    Bajić, Bojana Ž; Vučurović, Damjan G; Dodić, Siniša N; Grahovac, Jovana A; Dodić, Jelena M

    2017-09-04

    In this research a process and cost model for a xanthan production facility was developed using process simulation software (SuperPro Designer(®)). This work represents a novelty in the field for two reasons. One is that xanthan gum has been produced from several wastes but never from wastewaters from confectionery industries. The other more important is that the aforementioned software, which in intended exclusively for bioprocesses, is used for generating a base case, i.e. starting point for transferring the technology to industrial scales. Previously acquired experimental knowledge about using confectionery wastewaters from five different factories as substitutes for commercially used cultivation medium have been incorporated into the process model in order to obtain an economic viability of implementing such substrates. A lower initial sugar content in the medium based on wastewater (28.41 g/L) compared to the synthetic medium (30.00 g/L) gave a lower xanthan content at the end of cultivation (23.98 and 26.27 g/L, respectively). Although this resulted in somewhat poorer economic parameters, they were still in the range of being an investment of interest. Also the possibility of utilizing a cheap resource (waste) and reducing pollution that would result from its disposal has a positive effect on the environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Analyzing Company Economics Using the Leontief Open Production Model

    ERIC Educational Resources Information Center

    Laumakis, Paul J.

    2008-01-01

    This article details the application of an economic theory to the fiscal operation of a small engineering consulting firm. Nobel Prize-winning economist Wassily Leontief developed his general input-output economic theory in the mid-twentieth century to describe the flow of goods and services in the U.S. economy. We use one mathematical model that…

  5. Analyzing Company Economics Using the Leontief Open Production Model

    ERIC Educational Resources Information Center

    Laumakis, Paul J.

    2008-01-01

    This article details the application of an economic theory to the fiscal operation of a small engineering consulting firm. Nobel Prize-winning economist Wassily Leontief developed his general input-output economic theory in the mid-twentieth century to describe the flow of goods and services in the U.S. economy. We use one mathematical model that…

  6. Evaluation of the gas production economics of the gas hydrate cyclic thermal injection model

    SciTech Connect

    Kuuskraa, V.A.; Hammersheimb, E.; Sawyer, W.

    1985-05-01

    The objective of the work performed under this directive is to assess whether gas hydrates could potentially be technically and economically recoverable. The technical potential and economics of recovering gas from a representative hydrate reservoir will be established using the cyclic thermal injection model, HYDMOD, appropriately modified for this effort, integrated with economics model for gas production on the North Slope of Alaska, and in the deep offshore Atlantic. The results from this effort are presented in this document. In Section 1, the engineering cost and financial analysis model used in performing the economic analysis of gas production from hydrates -- the Hydrates Gas Economics Model (HGEM) -- is described. Section 2 contains a users guide for HGEM. In Section 3, a preliminary economic assessment of the gas production economics of the gas hydrate cyclic thermal injection model is presented. Section 4 contains a summary critique of existing hydrate gas recovery models. Finally, Section 5 summarizes the model modification made to HYDMOD, the cyclic thermal injection model for hydrate gas recovery, in order to perform this analysis.

  7. Economic analysis and assessment of syngas production using a modeling approach

    SciTech Connect

    Kim, Hakkwan; Parajuli, Prem B.; Yu, Fei; Columbus, Eugene P.

    2011-08-10

    Economic analysis and modeling are essential and important issues for the development of current feedstock and process technology for bio-gasification. The objective of this study was to develop an economic model and apply to predict the unit cost of syngas production from a micro-scale bio-gasification facility. An economic model was programmed in C++ computer programming language and developed using a parametric cost approach, which included processes to calculate the total capital costs and the total operating costs. The model used measured economic data from the bio-gasification facility at Mississippi State University. The modeling results showed that the unit cost of syngas production was $1.217 for a 60 Nm-3 h-1 capacity bio-gasifier. The operating cost was the major part of the total production cost. The equipment purchase cost and the labor cost were the largest part of the total capital cost and the total operating cost, respectively. Sensitivity analysis indicated that labor costs rank the top as followed by equipment cost, loan life, feedstock cost, interest rate, utility cost, and waste treatment cost. The unit cost of syngas production increased with the increase of all parameters with exception of loan life. The annual cost regarding equipment, labor, feedstock, waste treatment, and utility cost showed a linear relationship with percent changes, while loan life and annual interest rate showed a non-linear relationship. This study provides the useful information for economic analysis and assessment of the syngas production using a modeling approach.

  8. Computer Model for Economic Study of Unbleached Kraft Paperboard Production.

    DTIC Science & Technology

    1984-08-01

    steamn for (TRsN)...i~ machine turbines \\V based on HPPU lb ROSN @ SPRSN/ton steam/tlon product Paper Machine (eunt e.pe.pOes Headbox & (eunt o.pe.poes...demand for secondary pounds of steam produced). black liquor heater In recovery boiler area SVSE -Sales value of surplus electrical energy (pounds/ton

  9. Computer model for economic study of unbleached kraft paperboard production

    Treesearch

    Peter J. Ince

    1984-01-01

    Unbleached kraft paperboard is produced from wood fiber in an industrial papermaking process. A highly specific and detailed model of the process is presented. The model is also presented as a working computer program. A user of the computer program will provide data on physical parameters of the process and on prices of material inputs and outputs. The program is then...

  10. From Commodity Production to Sign Production: A Triple Triangle Model for Marx's Semiotics and Peirce's Economics.

    ERIC Educational Resources Information Center

    Kim, Joohoan

    Using the viewpoint of semiotics, this paper "re-reads" Karl Marx's labor theory of value and suggests a "triple triangle" model for commodity production and shows how this model could be a model for semiosis in general. The paper argues that there are three advantages to considering homogeneity of the sign production and the…

  11. Economics of stocker production.

    PubMed

    Peel, Derrell S

    2006-07-01

    The beef cattle industry, like any industry, is subject to economic signals to increase or decrease production according to short-run and long-run market conditions. Profitable stocker production is the result of careful matching of economic conditions to alternative animal production systems combined with sound animal and business management. The economics of stocker production are driven by the feeder cattle price-weight relation that combines broad market signals about how much production is needed with complex and subtle signals about how that production should be accomplished. The result is a dynamic set of values of gain that direct producers to adjust the level, type, and timing of stocker production according to changing market conditions.

  12. Modeling production functions and economic weights in intensive meat production of guinea pigs.

    PubMed

    Pascual, Mariam; Cruz, Danny Julio; Blasco, Agustín

    2017-06-15

    A profit function for a typical commercial farm of intensive guinea pig production was designed. The simulated farm contained 86 cages with a ratio of 7:1 females/males, with continuous mating. Kits were weaned at 15 days of age and slaughtered for meat production at 90 days of age. The absolute (EW) and relative economic weights of the main traits were calculated. The highest EW were kits produced per kindling (US$25), kits weaned per kindling (US$22), kits born alive per kindling (US$20), and the number of kindlings per female and year (US$12). Profit, returns, and costs per female and year were US$15, 68, and 53, respectively. Returns came from the production of young guinea pigs and discarded reproductive adults for meat production, 90 and 10% of the total returns. The highest costs were feeding and labor, 44 and 23% of the total cost. The EW and profit did not substantially change when simulating variations of ±20% in the prices of kilograms of fattening feed and kilograms of live weight of guinea pig, showing their robustness to future variations in market prices or to variations in prices between countries. The results obtained highlight the importance of the feeding costs in the guinea pig meat production.

  13. Economic production quantity model for items with continuous quality characteristic, rework and reject

    NASA Astrophysics Data System (ADS)

    Tsou, Jia-Chi; Hejazi, Seyed Reza; Rasti Barzoki, Morteza

    2012-12-01

    The economic production quantity (EPQ) model is a well-known and commonly used inventory control technique. However, the model is built on an unrealistic assumption that all the produced items need to be of perfect quality. Having relaxed this assumption, some researchers have studied the effects of the imperfect products on the inventory control techniques. This article, thus, attempts to develop an EPQ model with continuous quality characteristic and rework. To this end, this study assumes that a produced item follows a general distribution pattern, with its quality being perfect, imperfect or defective. The analysis of the model developed indicates that there is an optimal lot size, which generates minimum total cost. Moreover, the results show that the optimal lot size of the model equals that of the classical EPQ model in case imperfect quality percentage is zero or even close to zero.

  14. An economic production quantity model for deteriorating items with preventive maintenance policy and random machine breakdown

    NASA Astrophysics Data System (ADS)

    Agus Widyadana, Gede; Wee, Hui Ming

    2012-10-01

    In recent years, many researches on economic production quantity (EPQ) models with machine breakdown and preventive maintenance have been developed, but few of them have developed integrated models for deteriorating items. In this study, we develop EPQ models for deteriorating items with preventive maintenance, random machine breakdown and immediate corrective action. Corrective and preventive maintenance times are assumed to be stochastic and the unfulfilled demands are lost sales. Two EPQ models of uniform distribution and exponential distribution of corrective and maintenance times are developed. An example and sensitivity analysis is given to illustrate the models. For the exponential distribution model, it is shown that the corrective time parameter is one of the most sensitive parameters to the optimal total cost.

  15. An economic model of the manufacturers' aircraft production and airline earnings potential, volume 3

    NASA Technical Reports Server (NTRS)

    Kneafsey, J. T.; Hill, R. M.

    1978-01-01

    A behavioral explanation of the process of technological change in the U. S. aircraft manufacturing and airline industries is presented. The model indicates the principal factors which influence the aircraft (airframe) manufacturers in researching, developing, constructing and promoting new aircraft technology; and the financial requirements which determine the delivery of new aircraft to the domestic trunk airlines. Following specification and calibration of the model, the types and numbers of new aircraft were estimated historically for each airline's fleet. Examples of possible applications of the model to forecasting an individual airline's future fleet also are provided. The functional form of the model is a composite which was derived from several preceding econometric models developed on the foundations of the economics of innovation, acquisition, and technological change and represents an important contribution to the improved understanding of the economic and financial requirements for aircraft selection and production. The model's primary application will be to forecast the future types and numbers of new aircraft required for each domestic airline's fleet.

  16. Evaluation of the gas production economics of the gas hydrate cyclic thermal injection model. [Cyclic thermal injection

    SciTech Connect

    Kuuskraa, V.A.; Hammersheimb, E.; Sawyer, W.

    1985-05-01

    The objective of the work performed under this directive is to assess whether gas hydrates could potentially be technically and economically recoverable. The technical potential and economics of recovering gas from a representative hydrate reservoir will be established using the cyclic thermal injection model, HYDMOD, appropriately modified for this effort, integrated with economics model for gas production on the North Slope of Alaska, and in the deep offshore Atlantic. The results from this effort are presented in this document. In Section 1, the engineering cost and financial analysis model used in performing the economic analysis of gas production from hydrates -- the Hydrates Gas Economics Model (HGEM) -- is described. Section 2 contains a users guide for HGEM. In Section 3, a preliminary economic assessment of the gas production economics of the gas hydrate cyclic thermal injection model is presented. Section 4 contains a summary critique of existing hydrate gas recovery models. Finally, Section 5 summarizes the model modification made to HYDMOD, the cyclic thermal injection model for hydrate gas recovery, in order to perform this analysis.

  17. Process model and economic analysis of ethanol production from sugar beet raw juice as part of the cleaner production concept.

    PubMed

    Vučurović, Damjan G; Dodić, Siniša N; Popov, Stevan D; Dodić, Jelena M; Grahovac, Jovana A

    2012-01-01

    The batch fermentation process of sugar beet processing intermediates by free yeast cells is the most widely used method in the Autonomous Province of Vojvodina for producing ethanol as fuel. In this study a process and cost model was developed for producing ethanol from raw juice. The model can be used to calculate capital investment costs, unit production costs and operating costs for a plant producing 44 million l of 99.6% pure ethanol annually. In the sensitivity analysis the influence of sugar beet and yeast price, as well as the influence of recycled biomass on process economics, ethanol production costs and project feasibility was examined. The results of this study clearly demonstrate that the raw material costs have a significant influence on the expenses for producing ethanol. Also, the optimal percentage of recycled biomass turned out to be in the range from 50% to 70%.

  18. Comparative Research Productivity Measures for Economic Departments.

    ERIC Educational Resources Information Center

    Huettner, David A.; Clark, William

    1997-01-01

    Develops a simple theoretical model to evaluate interdisciplinary differences in research productivity between economics departments and related subjects. Compares the research publishing statistics of economics, finance, psychology, geology, physics, oceanography, chemistry, and geophysics. Considers a number of factors including journal…

  19. Comparative Research Productivity Measures for Economic Departments.

    ERIC Educational Resources Information Center

    Huettner, David A.; Clark, William

    1997-01-01

    Develops a simple theoretical model to evaluate interdisciplinary differences in research productivity between economics departments and related subjects. Compares the research publishing statistics of economics, finance, psychology, geology, physics, oceanography, chemistry, and geophysics. Considers a number of factors including journal…

  20. Applying complex models to poultry production in the future--economics and biology.

    PubMed

    Talpaz, H; Cohen, M; Fancher, B; Halley, J

    2013-09-01

    The ability to determine the optimal broiler feed nutrient density that maximizes margin over feeding cost (MOFC) has obvious economic value. To determine optimal feed nutrient density, one must consider ingredient prices, meat values, the product mix being marketed, and the projected biological performance. A series of 8 feeding trials was conducted to estimate biological responses to changes in ME and amino acid (AA) density. Eight different genotypes of sex-separate reared broilers were fed diets varying in ME (2,723-3,386 kcal of ME/kg) and AA (0.89-1.65% digestible lysine with all essential AA acids being indexed to lysine) levels. Broilers were processed to determine carcass component yield at many different BW (1.09-4.70 kg). Trial data generated were used in model constructed to discover the dietary levels of ME and AA that maximize MOFC on a per broiler or per broiler annualized basis (bird × number of cycles/year). The model was designed to estimate the effects of dietary nutrient concentration on broiler live weight, feed conversion, mortality, and carcass component yield. Estimated coefficients from the step-wise regression process are subsequently used to predict the optimal ME and AA concentrations that maximize MOFC. The effects of changing feed or meat prices across a wide spectrum on optimal ME and AA levels can be evaluated via parametric analysis. The model can rapidly compare both biological and economic implications of changing from current practice to the simulated optimal solution. The model can be exploited to enhance decision making under volatile market conditions.

  1. Intermediate inputs and economic productivity.

    PubMed

    Baptist, Simon; Hepburn, Cameron

    2013-03-13

    Many models of economic growth exclude materials, energy and other intermediate inputs from the production function. Growing environmental pressures and resource prices suggest that this may be increasingly inappropriate. This paper explores the relationship between intermediate input intensity, productivity and national accounts using a panel dataset of manufacturing subsectors in the USA over 47 years. The first contribution is to identify sectoral production functions that incorporate intermediate inputs, while allowing for heterogeneity in both technology and productivity. The second contribution is that the paper finds a negative correlation between intermediate input intensity and total factor productivity (TFP)--sectors that are less intensive in their use of intermediate inputs have higher productivity. This finding is replicated at the firm level. We propose tentative hypotheses to explain this association, but testing and further disaggregation of intermediate inputs is left for further work. Further work could also explore more directly the relationship between material inputs and economic growth--given the high proportion of materials in intermediate inputs, the results in this paper are suggestive of further work on material efficiency. Depending upon the nature of the mechanism linking a reduction in intermediate input intensity to an increase in TFP, the implications could be significant. A third contribution is to suggest that an empirical bias in productivity, as measured in national accounts, may arise due to the exclusion of intermediate inputs. Current conventions of measuring productivity in national accounts may overstate the productivity of resource-intensive sectors relative to other sectors.

  2. Breeding objectives for pigs in Kenya. I: bio-economic model development and application to smallholder production systems.

    PubMed

    Mbuthia, Jackson M; Rewe, Thomas O; Kahi, Alexander K

    2015-02-01

    A deterministic bio-economic model was developed and applied to evaluate biological and economic variables that characterize smallholder pig production systems in Kenya. Two pig production systems were considered namely, semi-intensive (SI) and extensive (EX). The input variables were categorized into biological variables including production and functional traits, nutritional variables, management variables and economic variables. The model factored the various sow physiological systems including gestation, farrowing, lactation, growth and development. The model was developed to evaluate a farrow to finish operation, but the results were customized to account for a farrow to weaner operation for a comparative analysis. The operations were defined as semi-intensive farrow to finish (SIFF), semi-intensive farrow to weaner (SIFW), extensive farrow to finish (EXFF) and extensive farrow to weaner (EXFW). In SI, the profits were the highest at KES. 74,268.20 per sow per year for SIFF against KES. 4026.12 for SIFW. The corresponding profits for EX were KES. 925.25 and KES. 626.73. Feed costs contributed the major part of the total costs accounting for 67.0, 50.7, 60.5 and 44.5 % in the SIFF, SIFW, EXFF and EXFW operations, respectively. The bio-economic model developed could be extended with modifications for use in deriving economic values for breeding goal traits for pigs under smallholder production systems in other parts of the tropics.

  3. Biofuel Crops Expansion: Evaluating the Impact on the Agricultural Water Scarcity Costs and Hydropower Production with Hydro Economic Modeling

    NASA Astrophysics Data System (ADS)

    Marques, G.

    2015-12-01

    Biofuels such as ethanol from sugar cane remain an important element to help mitigate the impacts of fossil fuels on the atmosphere. However, meeting fuel demands with biofuels requires technological advancement for water productivity and scale of production. This may translate into increased water demands for biofuel crops and potential for conflicts with incumbent crops and other water uses including domestic, hydropower generation and environmental. It is therefore important to evaluate the effects of increased biofuel production on the verge of water scarcity costs and hydropower production. The present research applies a hydro-economic optimization model to compare different scenarios of irrigated biofuel and hydropower production, and estimates the potential tradeoffs. A case study from the Araguari watershed in Brazil is provided. These results should be useful to (i) identify improved water allocation among competing economic demands, (ii) support water management and operations decisions in watersheds where biofuels are expected to increase, and (iii) identify the impact of bio fuel production in the water availability and economic value. Under optimized conditions, adoption of sugar cane for biofuel production heavily relies on the opportunity costs of other crops and hydropower generation. Areas with a lower value crop groups seem more suitable to adopt sugar cane for biofuel when the price of ethanol is sufficiently high and the opportunity costs of hydropower productions are not conflicting. The approach also highlights the potential for insights in water management from studying regional versus larger scales bundled systems involving water use, food production and power generation.

  4. Integrating health economics modeling in the product development cycle of medical devices: a Bayesian approach.

    PubMed

    Vallejo-Torres, Laura; Steuten, Lotte M G; Buxton, Martin J; Girling, Alan J; Lilford, Richard J; Young, Terry

    2008-01-01

    Medical device companies are under growing pressure to provide health-economic evaluations of their products. Cost-effectiveness analyses are commonly undertaken as a one-off exercise at the late stage of development of new technologies; however, the benefits of an iterative use of economic evaluation during the development process of new products have been acknowledged in the literature. Furthermore, the use of Bayesian methods within health technology assessment has been shown to be of particular value in the dynamic framework of technology appraisal when new information becomes available in the life cycle of technologies. In this study, we set out a methodology to adapt these methods for their application to directly support investment decisions in a commercial setting from early stages of the development of new medical devices. Starting with relatively simple analysis from the very early development phase and proceeding to greater depth of analysis at later stages, a Bayesian approach facilitates the incorporation of all available evidence and would help companies to make better informed choices at each decision point.

  5. Economic Benefits of Improved Information on Worldwide Crop Production: An Optimal Decision Model of Production and Distribution with Application to Wheat, Corn, and Soybeans

    NASA Technical Reports Server (NTRS)

    Andrews, J.

    1977-01-01

    An optimal decision model of crop production, trade, and storage was developed for use in estimating the economic consequences of improved forecasts and estimates of worldwide crop production. The model extends earlier distribution benefits models to include production effects as well. Application to improved information systems meeting the goals set in the large area crop inventory experiment (LACIE) indicates annual benefits to the United States of $200 to $250 million for wheat, $50 to $100 million for corn, and $6 to $11 million for soybeans, using conservative assumptions on expected LANDSAT system performance.

  6. Management Model for Economic Development.

    ERIC Educational Resources Information Center

    Harris, Edward

    An economic development model was formulated to foster and strengthen commerce and industry retention and expansion in the state of Illinois. The main thrust of the model was on increasing productivity, decreasing business failures, encouraging entrepreneurship, and creating a favorable business climate through community support. To meet these…

  7. Economics of hydrogen production

    SciTech Connect

    Gaines, L.L.; Wolsky, A.M.

    1984-01-01

    Much of the current interest in hydrogen (H/sub 2/) centers around its potential to displace oil and gas as a fuel. The results of this study should be useful to research and development managers making funding decisions, and they should also be of interest to energy analysts, economists, and proponents of a hydrogen economy. We examined the current costs of H/sub 2/ produced by commercially available technologies (from fossil fuels and by electrolysis) and projected these costs to 2010, to set cost goals for H/sub 2/ produced via new technologies. We also examined the sensitivity of H/sub 2/ costs to varying energy price forecasts, capital costs and the required rate of return on investment, and by-product credits. We find that conventionally produced H/sub 2/ will not break into the fuel market before 2010. 23 references, 19 figures, 12 tables.

  8. An economic production model for deteriorating items and time dependent demand with rework and multiple production setups

    NASA Astrophysics Data System (ADS)

    Uthayakumar, R.; Tharani, S.

    2017-04-01

    Recently, much emphasis has given to study the control and maintenance of production inventories of the deteriorating items. Rework is one of the main issues in reverse logistic and green supply chain, since it can reduce production cost and the environmental problem. Many researchers have focused on developing rework model, but few of them have developed model for deteriorating items. Due to this fact, we take up productivity and rework with deterioration as the major concern in this paper. In this paper, a production-inventory model with deteriorative items in which one cycle has n production setups and one rework setup (n, 1) policy is considered for deteriorating items with stock-dependent demand in case 1 and exponential demand in case 2. An effective iterative solution procedure is developed to achieve optimal time, so that the total cost of the system is minimized. Numerical and sensitivity analyses are discussed to examine the outcome of the proposed solution procedure presented in this research.

  9. An economic, sustainability, and energetic model of biodiesel production from microalgae.

    PubMed

    Delrue, F; Setier, P-A; Sahut, C; Cournac, L; Roubaud, A; Peltier, G; Froment, A-K

    2012-05-01

    A new process evaluation methodology of microalgae biodiesel has been developed. Based on four evaluation criteria, i.e. the net energy ratio (NER), biodiesel production costs, greenhouse gases (GHG) emission rate and water footprint, the model compares various technologies for each step of the process, from cultivation to oil upgrading. An innovative pathway (hybrid raceway/PBR cultivation system, belt filter press for dewatering, wet lipid extraction, oil hydrotreating and anaerobic digestion of residues) shows good results in comparison to a reference pathway (doubled NER, lower GHG emission rate and water footprint). The production costs are still unfavourable (between 1.94 and 3.35 €/L of biodiesel). The most influential parameters have been targeted through a global sensitivity analysis and classified: (i) lipid productivity, (ii) the cultivation step, and (iii) the downstream processes. The use of low-carbon energy sources is required to achieve significant reductions of the biodiesel GHG emission rate compared to petroleum diesel. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Mycotoxins in ethanol co-products: modeling economic impacts on the livestock industry and management strategies.

    PubMed

    Wu, Felicia; Munkvold, Gary P

    2008-06-11

    The rapidly expanding U.S. ethanol industry is generating a growing supply of co-products, mostly in the form of dried distillers' grain and solubles (DDGS) or wet distillers' grains (WDG). In the United States, 90% of the co-products of maize-based ethanol are fed to livestock. An unintended consequence is that animals are likely to be fed higher levels of mycotoxins, which are concentrated up to three times in DDGS compared to grain. The model developed in this study estimates current losses to the swine industry from weight gain reduction due to fumonisins in added DDGS at $9 million ($2-18 million) annually. If there is complete market penetration of DDGS in swine feed with 20% DDGS inclusion in swine feed and fumonisins are not controlled, losses may increase to $147 million ($29-293 million) annually. These values represent only those losses attributable to one mycotoxin on one adverse outcome on one species. The total loss due to mycotoxins in DDGS could be significantly higher due to additive or multiplicative effects of multiple mycotoxins on animal health. If mycotoxin surveillance is implemented by ethanol producers, losses are shifted among multiple stakeholders. Solutions to this problem include methods to reduce mycotoxin contamination in both pre- and postharvest maize.

  11. Economic communication model set

    NASA Astrophysics Data System (ADS)

    Zvereva, Olga M.; Berg, Dmitry B.

    2017-06-01

    This paper details findings from the research work targeted at economic communications investigation with agent-based models usage. The agent-based model set was engineered to simulate economic communications. Money in the form of internal and external currencies was introduced into the models to support exchanges in communications. Every model, being based on the general concept, has its own peculiarities in algorithm and input data set since it was engineered to solve the specific problem. Several and different origin data sets were used in experiments: theoretic sets were estimated on the basis of static Leontief's equilibrium equation and the real set was constructed on the basis of statistical data. While simulation experiments, communication process was observed in dynamics, and system macroparameters were estimated. This research approved that combination of an agent-based and mathematical model can cause a synergetic effect.

  12. Habitat Size Optimization of the O'Neill - Glaser Economic Model for Space Solar Satellite Production

    NASA Technical Reports Server (NTRS)

    Curreri, Peter A.; Detweiler, Michael

    2010-01-01

    Creating large space habitats by launching all materials from Earth is prohibitively expensive. Using space resources and space based labor to build space solar power satellites can yield extraordinary profits after a few decades. The economic viability of this program depends on the use of space resources and space labor. To maximize the return on the investment, the early use of high density bolo habitats is required. Other shapes do not allow for the small initial scale required for a quick population increase in space. This study found that 5 Man Year, or 384 person bolo high density habitats will be the most economically feasible for a program started at year 2010 and will cause a profit by year 24 of the program, put over 45,000 people into space, and create a large system of space infrastructure for the further exploration and development of space.

  13. Ledipasvir/sofosbuvir regimens for chronic hepatitis C infection: Insights from a work productivity economic model from the United States.

    PubMed

    Younossi, Zobair M; Jiang, Yushan; Smith, Nathaniel J; Stepanova, Maria; Beckerman, Rachel

    2015-05-01

    Patients with chronic hepatitis C (CHC) exhibit reduced work productivity owing to their disease. Historically, most regimens indicated for CHC genotype 1 (GT1) patients were administered with pegylated interferon (Peg-IFN) and/or ribavirin (RBV), which further compromised work productivity during treatment. The aim of this study was to model the impact of LDV/SOF (ledipasvir/sofosbuvir), the first Peg-IFN- and RBV-free regimen for CHC GT1 patients, on work productivity from an economic perspective, compared to receiving no treatment. The WPAI-SHP (Work Productivity and Activity Index-Specific Health Problem) questionnaire was administered to patients across the ION clinical trials (N = 1,923 U.S. patients). Before initiation of treatment, patients with CHC GT1 in the ION trials exhibited absenteeism and presenteeism impairments of 2.57% and 7.58%, respectively. Patients with cirrhosis exhibited greater work productivity impairment than patients without cirrhosis. In total, 93.21% of U.S. patients in the ION trials achieved SVR; these patients exhibited absenteeism and presenteeism impairments of 2.62% (P = 0.76, when compared to baseline) and 3.53% (P < 0.0001), respectively. Monetizing these data to the entire U.S. population, our model projects an annual societal cost of $7.1 billion owing to productivity loss in untreated GT1 CHC patients. Our model projects that, when compared to no treatment, treating all CHC GT1 patients with a regimen with very high viral eradication rates (LDV/SOF) would translate to annual productivity loss savings of $2.7 billion over a 1-year time horizon. Patients with untreated HCV impose a substantial societal burden owing to reduced work productivity. As a result of improvements in work productivity, treatment of CHC GT1 patients with LDV/SOF-based regimens is likely to result in significant cost savings from a societal perspective, relative to no treatment. © 2015 by the American Association for the Study of Liver

  14. The economics of food production.

    PubMed

    Upton, M

    1993-01-01

    Although world average food production per person is increasing there are many countries, particularly in sub-Saharan Africa, where production has fallen in recent decades. The economic analysis of the world food problem concerns the dynamics of production, income, growth, demand and trade. The 'law of diminishing returns' suggests that labour incomes fall as population density increases. Capital investment and technological change, particularly with a land-saving bias, can overcome this effect. Such land-saving innovations are less appropriate where population densities are lower, as in much of sub-Saharan Africa. Innovations which reduce risk, such as stress- and disease-resistant crop varieties, may be more attractive to farmers. Communal or government action is required to ensure sustainability of food production; to reduce risk, through price stabilization, possibly crop insurance and contingency plans for famine relief; to promote equity and to ensure competitive market conditions. Public funding of agricultural research is necessary to promote growth in food supplies. If increases in supply do not keep pace with growth in demand, food prices rise, attracting resources into food production. If supply grows faster, food prices and farm incomes fall, driving resources out of agriculture. Resources may not move fast enough to correct imbalances. Primary producers are likely to face deteriorating terms of trade. Linkages between food production and other sectors are weak, so primary exports are not a good basis for economic development. Import substitution strategies may damage agriculture. Structural adjustment regimes have been adopted in some countries to correct imbalances and provide an incentive for farmers to increase production. Associated reductions in public expenditure may have a contrary impact.

  15. Conversion of bioprocess ethanol to industrial chemical products - Applications of process models for energy-economic assessments

    NASA Technical Reports Server (NTRS)

    Rohatgi, Naresh K.; Ingham, John D.

    1992-01-01

    An assessment approach for accurate evaluation of bioprocesses for large-scale production of industrial chemicals is presented. Detailed energy-economic assessments of a potential esterification process were performed, where ethanol vapor in the presence of water from a bioreactor is catalytically converted to ethyl acetate. Results show that such processes are likely to become more competitive as the cost of substrates decreases relative to petrolium costs. A commercial ASPEN process simulation provided a reasonably consistent comparison with energy economics calculated using JPL developed software. Detailed evaluations of the sensitivity of production cost to material costs and annual production rates are discussed.

  16. Conversion of bioprocess ethanol to industrial chemical products - Applications of process models for energy-economic assessments

    NASA Technical Reports Server (NTRS)

    Rohatgi, Naresh K.; Ingham, John D.

    1992-01-01

    An assessment approach for accurate evaluation of bioprocesses for large-scale production of industrial chemicals is presented. Detailed energy-economic assessments of a potential esterification process were performed, where ethanol vapor in the presence of water from a bioreactor is catalytically converted to ethyl acetate. Results show that such processes are likely to become more competitive as the cost of substrates decreases relative to petrolium costs. A commercial ASPEN process simulation provided a reasonably consistent comparison with energy economics calculated using JPL developed software. Detailed evaluations of the sensitivity of production cost to material costs and annual production rates are discussed.

  17. Economics and Maximum Entropy Production

    NASA Astrophysics Data System (ADS)

    Lorenz, R. D.

    2003-04-01

    Price differentials, sales volume and profit can be seen as analogues of temperature difference, heat flow and work or entropy production in the climate system. One aspect in which economic systems exhibit more clarity than the climate is that the empirical and/or statistical mechanical tendency for systems to seek a maximum in production is very evident in economics, in that the profit motive is very clear. Noting the common link between 1/f noise, power laws and Self-Organized Criticality with Maximum Entropy Production, the power law fluctuations in security and commodity prices is not inconsistent with the analogy. There is an additional thermodynamic analogy, in that scarcity is valued. A commodity concentrated among a few traders is valued highly by the many who do not have it. The market therefore encourages via prices the spreading of those goods among a wider group, just as heat tends to diffuse, increasing entropy. I explore some empirical price-volume relationships of metals and meteorites in this context.

  18. The economics of dairy production.

    PubMed

    Wolf, Christopher A

    2003-07-01

    structure and regional pattern of dairy farm size and production. For the most part, however, the policy effects have been of indirect nature. The Pacific region has grown (despite having the lowest average price) by taking advantage of economies of size by specializing in milking cows. The United States dairy industry is a technologically advanced, well-managed, and economically important sector of United States agriculture. Future challenges include the ability to remain viable economically while dealing with environmental and social sustainability issues in the form of new constraints from formal policies and from consumer perceptions.

  19. Modeling recent economic debates

    NASA Astrophysics Data System (ADS)

    Skiadas, Christos H.

    The previous years' disaster in the stock markets all over the world and the resulting economic crisis lead to serious criticisms of the various models used. It was evident that large fluctuations and sudden losses may occur even in the case of a well organized and supervised context as it looks to be the European Union. In order to explain the economic systems, we explore models of interacting and conflicting populations. The populations are conflicting into the same environment (a Stock Market or a Group of Countries as the EU). Three models where introduced 1) the Lotka-Volterra 2) the Lanchester or the Richardson model and 3) a new model for two conflicting populations. These models assume immediate interaction between the two conflicting populations. This is usually not the case in a stock market or between countries as delays in the information process arise. The main rules present include mutual interaction between adopters, potential adopters, word-of-mouth communication and of course by taking into consideration the innovation diffusion process. In a previous paper (Skiadas, 2010 [9]) we had proposed and analyzed a model including mutual interaction with delays due to the innovation diffusion process. The model characteristics where expressed by third order terms providing four characteristic symmetric stationary points. In this paper we summarize the previous results and we analyze the case of a non-symmetric case where the leading part receives the information immediately while the second part receives the information following a delay mechanism due to the innovation diffusion process (the spread of information) which can be expressed by a third order term. In the later case the non-symmetric process leads to gains of the leading part while the second part oscillates between gains and losses during time.

  20. Economic and Physical Modeling of Land Use in GCAM 3.0 and an Application to Agricultural Productivity, Land, and Terrestrial Carbon

    SciTech Connect

    Wise, Marshall A.; Calvin, Katherine V.; Kyle, G. Page; Luckow, Patrick; Edmonds, James A.

    2014-09-01

    We explore the impact of changes in agricultural productivity on global land use and terrestrial carbon using the new agriculture and land use modeling approach developed for Global Change Assessment Model (GCAM) version 3.0. This approach models economic land use decisions with regional, physical, and technological specificity while maintaining economic and physical integration with the rest of the GCAM model. Physical land characteristics and quantities are tracked explicitly, and crop production practices are modeled discretely to facilitate coupling with physical models. Economic land allocation is modeled with non-linear functions in a market equilibrium rather than through a constrained optimization. In this paper, we explore three scenarios of future agriculture productivity in all regions of the globe over this century, ranging from a high growth to a zero growth level. The higher productivity growth scenario leads to lower crop prices, increased production of crops in developing nations, preservation of global forested lands and lower terrestrial carbon emissions. The scenario with no productivity improvement results in higher crop prices, an expansion of crop production in the developed world, loss of forested lands globally, and higher terrestrial carbon emissions.

  1. Gary Becker: Model Economic Scientist.

    PubMed

    Heckman, James J

    2015-05-01

    This paper presents Gary Becker's approach to conducting creative, empirically fruitful economic research. It describes the traits and methodology that made him such a productive and influential scholar.

  2. Application of integrated production and economic models to estimate the impact of Schmallenberg virus for various sheep production types in the UK and France

    PubMed Central

    Alarcon, Pablo; Häsler, Barbara; Raboisson, Didier; Waret-Szkuta, Agnes; Corbière, Fabien; Rushton, Jonathan

    2014-01-01

    Objective The present study aimed to estimate and compare the economic impact of Schmallenberg virus (SBV) in different sheep production holdings using partial budget and gross margin analyses in combination with production models. Participants The sheep production types considered were lowland spring lambing, upland spring lambing and early lambing flocks in the UK, and grass lamb flocks of the Centre and West of France, extensive lambing flocks and dairy sheep flocks in France. Methodology Two disease scenarios with distinct input parameters associated with reproductive problems were considered: low and high impact. Sensitivity analyses were performed for the most uncertain input parameters, and the models were run with all of the lowest and highest values to estimate the range of disease impact. Results The estimated net SBV disease cost per year and ewe for the UK was £19.65–£20.85 for the high impact scenario and £6.40–£6.58 for the low impact scenario. No major differences were observed between the different production types. For France, the net SBV disease cost per year and ewe for the meat sheep holdings was £15.59–£17.20 for the high impact scenario and £4.75–£5.26 for the low impact scenario. For the dairy sheep, the costs per year and ewe were £29.81 for the high impact scenario and £10.34 for the low impact scenario. Conclusions The models represent a useful decision support tool for farmers and veterinarians who are facing decisions regarding disease control measures. They allow estimating disease impact on a farm accounting for differing production practices, which creates the necessary basis for cost effectiveness analysis of intervention strategies, such as vaccination. PMID:26392876

  3. Farm systems assessment of bioenergy feedstock production: Integrating bio-economic models and life cycle analysis approaches.

    PubMed

    Glithero, N J; Ramsden, S J; Wilson, P

    2012-06-01

    Climate change and energy security concerns have driven the development of policies that encourage bioenergy production. Meeting EU targets for the consumption of transport fuels from bioenergy by 2020 will require a large increase in the production of bioenergy feedstock. Initially an increase in 'first generation' biofuels was observed, however 'food competition' concerns have generated interest in second generation biofuels (SGBs). These SGBs can be produced from co-products (e.g. cereal straw) or energy crops (e.g. miscanthus), with the former largely negating food competition concerns. In order to assess the sustainability of feedstock supply for SGBs, the financial, environmental and energy costs and benefits of the farm system must be quantified. Previous research has captured financial costs and benefits through linear programming (LP) approaches, whilst environmental and energy metrics have been largely been undertaken within life cycle analysis (LCA) frameworks. Assessing aspects of the financial, environmental and energy sustainability of supplying co-product second generation biofuel (CPSGB) feedstocks at the farm level requires a framework that permits the trade-offs between these objectives to be quantified and understood. The development of a modelling framework for Managing Energy and Emissions Trade-Offs in Agriculture (MEETA Model) that combines bio-economic process modelling and LCA is presented together with input data parameters obtained from literature and industry sources. The MEETA model quantifies arable farm inputs and outputs in terms of financial, energy and emissions results. The model explicitly captures fertiliser: crop-yield relationships, plus the incorporation of straw or removal for sale, with associated nutrient impacts of incorporation/removal on the following crop in the rotation. Key results of crop-mix, machinery use, greenhouse gas (GHG) emissions per kg of crop product and energy use per hectare are in line with previous

  4. Farm systems assessment of bioenergy feedstock production: Integrating bio-economic models and life cycle analysis approaches

    PubMed Central

    Glithero, N.J.; Ramsden, S.J.; Wilson, P.

    2012-01-01

    Climate change and energy security concerns have driven the development of policies that encourage bioenergy production. Meeting EU targets for the consumption of transport fuels from bioenergy by 2020 will require a large increase in the production of bioenergy feedstock. Initially an increase in ‘first generation’ biofuels was observed, however ‘food competition’ concerns have generated interest in second generation biofuels (SGBs). These SGBs can be produced from co-products (e.g. cereal straw) or energy crops (e.g. miscanthus), with the former largely negating food competition concerns. In order to assess the sustainability of feedstock supply for SGBs, the financial, environmental and energy costs and benefits of the farm system must be quantified. Previous research has captured financial costs and benefits through linear programming (LP) approaches, whilst environmental and energy metrics have been largely been undertaken within life cycle analysis (LCA) frameworks. Assessing aspects of the financial, environmental and energy sustainability of supplying co-product second generation biofuel (CPSGB) feedstocks at the farm level requires a framework that permits the trade-offs between these objectives to be quantified and understood. The development of a modelling framework for Managing Energy and Emissions Trade-Offs in Agriculture (MEETA Model) that combines bio-economic process modelling and LCA is presented together with input data parameters obtained from literature and industry sources. The MEETA model quantifies arable farm inputs and outputs in terms of financial, energy and emissions results. The model explicitly captures fertiliser: crop-yield relationships, plus the incorporation of straw or removal for sale, with associated nutrient impacts of incorporation/removal on the following crop in the rotation. Key results of crop-mix, machinery use, greenhouse gas (GHG) emissions per kg of crop product and energy use per hectare are in line with

  5. Techno Economic Model

    SciTech Connect

    2010-04-01

    The Technoeconomic model is a computational model of a lignocellulosic biorefinery that can be used by industry to establish benchmarks of performance and risk-benefit analysis in order to assess the potential impact of cutting edge technologies. The model can be used to evaluate, guide, and optimize research efforts, biorefinery design, and process operation. The model will help to reduce the risk of commercial investment and development of biorefineries and help steer future research to those parts of the refining process in need of further developments for biofuels to be cost competitive. We have now aded modules for the following sections: feed handling, pretreatment, fermentation, product and water recovery, waste treatment, and steam/electricity generation. We have incorporated a kinetic model for microorganism growth and production of ethanol, inclouding toxin inhibition. For example, the feed handling section incorporates information regarding feedstock transport distance-dependent costs. The steam and electricity generation section now includes a turbogenerator that supplies power to be used by other unit operations and contains equations for efficiency calculations.

  6. Economics of Gypsum Production in Iran

    NASA Astrophysics Data System (ADS)

    Esmaeili, Abdoulkarim

    The purpose of this research is to analyze the economics of gypsum production in Iran. The trend in production cost, selling price and profit are used to investigate economics of gypsum production. In addition, the multivariate time series method is used to determine factors affecting gypsum price in domestic market. The results indicated that due to increase in production and inflation, profitability of gypsum production has decreased during recent years. It is concluded that tariff and non-tariff barriers on mines machinery are among reasons for increasing production cost in Iranian gypsum mines. Decreasing such barriers could increase profitability of gypsum production in Iran.

  7. Gary Becker: Model Economic Scientist

    PubMed Central

    2015-01-01

    This paper presents Gary Becker’s approach to conducting creative, empirically fruitful economic research. It describes the traits and methodology that made him such a productive and influential scholar. PMID:26705367

  8. Derivation of economic values for production traits in aquaculture species.

    PubMed

    Janssen, Kasper; Berentsen, Paul; Besson, Mathieu; Komen, Hans

    2017-01-05

    In breeding programs for aquaculture species, breeding goal traits are often weighted based on the desired gains but economic gain would be higher if economic values were used instead. The objectives of this study were: (1) to develop a bio-economic model to derive economic values for aquaculture species, (2) to apply the model to determine the economic importance and economic values of traits in a case-study on gilthead seabream, and (3) to validate the model by comparison with a profit equation for a simplified production system. A bio-economic model was developed to simulate a grow-out farm for gilthead seabream, and then used to simulate gross margin at the current levels of the traits and after one genetic standard deviation change in each trait with the other traits remaining unchanged. Economic values were derived for the traits included in the breeding goal: thermal growth coefficient (TGC), thermal feed intake coefficient (TFC), mortality rate (M), and standard deviation of harvest weight ([Formula: see text]). For a simplified production system, improvement in TGC was assumed to affect harvest weight instead of growing period. Using the bio-economic model and a profit equation, economic values were derived for harvest weight, cumulative feed intake at harvest, and overall survival. Changes in gross margin showed that the order of economic importance of the traits was: TGC, TFC, M, and [Formula: see text]. Economic values in € (kg production)(-1) (trait unit)(-1) were: 0.40 for TGC, -0.45 for TFC, -7.7 for M, and -0.0011 to -0.0010 for [Formula: see text]. For the simplified production system, similar economic values were obtained with the bio-economic model and the profit equation. The advantage of the profit equation is its simplicity, while that of the bio-economic model is that it can be applied to any aquaculture species, because it can include any limiting factor and/or environmental condition that affects production. We confirmed the validity of

  9. Conceptual models underlying economic analysis of animal health and welfare with the inclusion of three components: people, products and resources.

    PubMed

    Hennessy, D A

    2017-04-01

    Infectious animal diseases can spill across farm boundaries, so effective management requires coordinated responses. Costs and benefits from the management of infectious diseases are such that those who make the decisions have weak incentives to act, the levels of goods and services produced from animal agriculture are probably smaller than is socially optimal and resources are likely wasted. This work provides an overview of the existing literature on conceptual economic models in animal disease management, paying particular attention to inadequate incentives to make the required biosecurity efforts. A disease transmission model follows, emphasising policy and management issues which need to be addressed to enhance the benefits that consumers and producers obtain from animal protein markets. The article concludes with comments and suggestions on tackling infectious disease as a public good, and on directions for future research.

  10. Economical Production of Pu-238

    SciTech Connect

    Steven D. Howe; Douglas Crawford; Jorge Navarro; Terry Ring

    2013-02-01

    All space exploration missions traveling beyond Jupiter must use radioisotopic power sources for electrical power. The best isotope to power these sources is plutonium-238. The US supply of Pu-238 is almost exhausted and will be gone within the next decade. The Department of Energy has initiated a production program with a $10M allocation from NASA but the cost is estimated at over $100 M to get to production levels. The Center for Space Nuclear Research has conceived of a potentially better process to produce Pu-238 earlier and for significantly less cost. The new process will also produce dramatically less waste. Potentially, the front end costs could be provided by private industry such that the government only had to pay for the product produced. Under a NASA Phase I NIAC grant, the CSNR has evaluated the feasibility of using a low power, commercially available nuclear reactor to produce at least 1.5 kg of Pu-238 per year. The impact on the neutronics of the reactor have been assessed, the amount of Neptunium target material estimated, and the production rates calculated. In addition, the size of the post-irradiation processing facility has been established. In addition, a new method for fabricating the Pu-238 product into the form used for power sources has been identified to reduce the cost of the final product. In short, the concept appears to be viable, can produce the amount of Pu-238 needed to support the NASA missions, can be available within a few years, and will cost significantly less than the current DOE program.

  11. Ethanol fuels: use, production, and economics. [Textbook

    SciTech Connect

    Not Available

    1981-05-01

    This text is intended for use at the junior college or community college level. It contains the following chapters: issues and concerns; the production and use of alcohol fuels; ethanol-potential as fuel extender or alternative; ethanol production plausibility and feasibility in specific situations, feedstock considerations; introduction to basis chemistry, microbiology, and heat transfer; production of ethanol fuel; plant design considerations; plant operations; production economics; and safety. (MHR)

  12. Switchgrass: Production, Economics, and Net Energy

    USDA-ARS?s Scientific Manuscript database

    The critical questions for a biomass bioenergy production system are: • What are the economics? • Is energy from biomass net energy positive? • Is production system information available and verified? • Is the system sustainable? To address these questions, ten farmers in the mid-continental USA w...

  13. The behavioral economics of production.

    PubMed Central

    Allison, J; English, J

    1993-01-01

    In two experiments, thirsty rats licked an empty spout instrumentally for water delivered at a neighboring spout. Each such pair of spouts constituted a work station, and one, two, or three stations were available in the test enclosure. In 1-hr sessions, the rats worked alone or in the company of 1 or 2 other rats, and performed either five, 10, or 40 licks at the empty spout for each water delivery. The total number of empty-spout licks, summed across rats and stations, increased with the empty-lick requirement and, with some exceptions, the number of rats in the enclosure and the number of work stations available. A Cobb-Douglas production function, with instrumental responding as an output and the three independent variables as inputs, accounted for a significant percentage of the variance. Contrary to that function, output failed to increase with additional rats (or work stations) when the number of work stations (or rats) was relatively small. PMID:8283148

  14. High titer L-lactic acid production from corn stover with minimum wastewater generation and techno-economic evaluation based on Aspen plus modeling.

    PubMed

    Liu, Gang; Sun, Jiaoe; Zhang, Jian; Tu, Yi; Bao, Jie

    2015-12-01

    Technological potentials of l-lactic acid production from corn stover feedstock were investigated by experimental and techno-economic studies. An optimal performance with 104.5 g/L in l-lactic acid titer and 71.5% in overall yield from cellulose in corn stover to l-lactic acid using an engineered Pediococcus acidilactici strain were obtained by overcoming several technical barriers. A rigorous Aspen plus model for l-lactic acid production starting from dry dilute acid pretreated and biodetoxified corn stover was developed. The techno-economic analysis shows that the minimum l-lactic acid selling price (MLSP) was $0.523 per kg, which was close to that of the commercial l-lactic acid produced from starch feedstock, and 24% less expensive than that of ethanol from corn stover, even though the xylose utilization was not considered. The study provided a prototype of industrial application and an evaluation model for high titer l-lactic acid production from lignocellulose feedstock. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Process engineering economics of bioethanol production.

    PubMed

    Galbe, Mats; Sassner, Per; Wingren, Anders; Zacchi, Guido

    2007-01-01

    This work presents a review of studies on the process economics of ethanol production from lignocellulosic materials published since 1996. Our objective was to identify the most costly process steps and the impact of various parameters on the final production cost, e.g. plant capacity, raw material cost, and overall product yield, as well as process configuration. The variation in estimated ethanol production cost is considerable, ranging from about 0.13 to 0.81 US$ per liter ethanol. This can be explained to a large extent by actual process differences and variations in the assumptions underlying the techno-economic evaluations. The most important parameters for the economic outcome are the feedstock cost, which varied between 30 and 90 US$ per metric ton in the papers studied, and the plant capacity, which influences the capital cost. To reduce the ethanol production cost it is necessary to reach high ethanol yields, as well as a high ethanol concentration during fermentation, to be able to decrease the energy required for distillation and other downstream process steps. Improved pretreatment methods, enhanced enzymatic hydrolysis with cheaper and more effective enzymes, as well as improved fermentation systems present major research challenges if we are to make lignocellulose-based ethanol production competitive with sugar- and starch-based ethanol. Process integration, either internally or externally with other types of plants, e.g. heat and power plants, also offers a way of reducing the final ethanol production cost.

  16. Model confirmation in climate economics

    PubMed Central

    Millner, Antony; McDermott, Thomas K. J.

    2016-01-01

    Benefit–cost integrated assessment models (BC-IAMs) inform climate policy debates by quantifying the trade-offs between alternative greenhouse gas abatement options. They achieve this by coupling simplified models of the climate system to models of the global economy and the costs and benefits of climate policy. Although these models have provided valuable qualitative insights into the sensitivity of policy trade-offs to different ethical and empirical assumptions, they are increasingly being used to inform the selection of policies in the real world. To the extent that BC-IAMs are used as inputs to policy selection, our confidence in their quantitative outputs must depend on the empirical validity of their modeling assumptions. We have a degree of confidence in climate models both because they have been tested on historical data in hindcasting experiments and because the physical principles they are based on have been empirically confirmed in closely related applications. By contrast, the economic components of BC-IAMs often rely on untestable scenarios, or on structural models that are comparatively untested on relevant time scales. Where possible, an approach to model confirmation similar to that used in climate science could help to build confidence in the economic components of BC-IAMs, or focus attention on which components might need refinement for policy applications. We illustrate the potential benefits of model confirmation exercises by performing a long-run hindcasting experiment with one of the leading BC-IAMs. We show that its model of long-run economic growth—one of its most important economic components—had questionable predictive power over the 20th century. PMID:27432964

  17. Model confirmation in climate economics.

    PubMed

    Millner, Antony; McDermott, Thomas K J

    2016-08-02

    Benefit-cost integrated assessment models (BC-IAMs) inform climate policy debates by quantifying the trade-offs between alternative greenhouse gas abatement options. They achieve this by coupling simplified models of the climate system to models of the global economy and the costs and benefits of climate policy. Although these models have provided valuable qualitative insights into the sensitivity of policy trade-offs to different ethical and empirical assumptions, they are increasingly being used to inform the selection of policies in the real world. To the extent that BC-IAMs are used as inputs to policy selection, our confidence in their quantitative outputs must depend on the empirical validity of their modeling assumptions. We have a degree of confidence in climate models both because they have been tested on historical data in hindcasting experiments and because the physical principles they are based on have been empirically confirmed in closely related applications. By contrast, the economic components of BC-IAMs often rely on untestable scenarios, or on structural models that are comparatively untested on relevant time scales. Where possible, an approach to model confirmation similar to that used in climate science could help to build confidence in the economic components of BC-IAMs, or focus attention on which components might need refinement for policy applications. We illustrate the potential benefits of model confirmation exercises by performing a long-run hindcasting experiment with one of the leading BC-IAMs. We show that its model of long-run economic growth-one of its most important economic components-had questionable predictive power over the 20th century.

  18. Economic Analysis. Computer Simulation Models.

    ERIC Educational Resources Information Center

    Sterling Inst., Washington, DC. Educational Technology Center.

    A multimedia course in economic analysis was developed and used in conjunction with the United States Naval Academy. (See ED 043 790 and ED 043 791 for final reports of the project evaluation and development model.) This volume of the text discusses the simulation of behavioral relationships among variable elements in an economy and presents…

  19. Estimating the Performance and Economic Value of Multiple Concentrating Solar Power Technologies in a Production Cost Model

    SciTech Connect

    Jorgenson, Jennie; Denholm, Paul; Mehos, Mark; Turchi, Craig

    2013-12-01

    Concentrating solar power with thermal energy storage (CSP-TES) is a unique source of renewable energy in that the solar thermal energy can be dispatched similarly to conventional thermal generation. However, CSP-TES plants are energy-limited, meaning that their response might be restricted by solar availability. Therefore, the use of this limited solar energy must be optimally scheduled toprovide the greatest value to the system. The timing of CSP-TES dispatch depends on a variety of factors, including electricity demand patterns, the penetration of variable generation sources, and the configuration of the CSP-TES plant itself. We use an established CSP-TES modeling framework in a commercially available production cost model to compare the dispatch and value of two CSP-TEStechnologies (molten salt towers and parabolic troughs) in a Colorado test system. In addition, we consider a range of configuration parameters, such as the solar multiple and thermal energy storage limit, to evaluate how the operational and capacity value varies with plant configuration.

  20. Model space of economic events

    NASA Astrophysics Data System (ADS)

    Romanovsky, M. Yu.

    A method for constructing the model or virtual space of economic events when economic objects can be considered as material ones is suggested. We describe change of share rates in time at stock markets as the potential difference of attracted bodies in time in this virtual space. Each share of each enterprise is displayed by a single particle with a unit “charge”. It is shown that the random value of potential difference at the origin of coordinates measured at a definite time interval has the probability density coinciding with the known distribution of “Levy flights” or “Levy walks”. A distribution of alteration in time of the “Standard and Poor” index value obtained by Mantegna and Stanley (they shown that it is the “Levy walks” distribution too) (Mantegna and Stanley, Nature 376 (1995) 46) is used for determination of the introduced potential dependence on coordinates in the model space. A simple phenomenological model of interaction potential is introduced. The potential law of each particle turns out to be closed to r-2.14 in the minimum possible three-dimensional model space. This model permits calculation of time of random potential correlations at a certain point of the model space. These correlations could characterize the time period of making a decision by an investor at stock exchange. It is shown that this time is notably shorter in unstable periods (1987). A “microscopical” model of interaction in the virtual space is also discussed.

  1. Thermodynamic, economic, and environmental modeling of hydrogen (H2) co-production integrated with stationary Fuel Cell Systems (FCS).

    SciTech Connect

    Margalef, Pere; Brouwer, Jack; Colella, Whitney; Rankin, Aerel; Sun, Amy Cha-Tien

    2009-05-01

    The objective of this project is to analyze the potential for hydrogen co-production within high-temperature stationary fuel cell systems (H2-FCS) and identify novel designs with minimum CO2 and cost. Specific objectives are to (1) develop novel H2-FCS designs that release low greenhouse gas emissions; and (2) develop novel H2-FCS designs with low hydrogen production cost.

  2. Economic modeling and sensitivity analysis.

    PubMed

    Hay, J W

    1998-09-01

    The field of pharmacoeconomics (PE) faces serious concerns of research credibility and bias. The failure of researchers to reproduce similar results in similar settings, the inappropriate use of clinical data in economic models, the lack of transparency, and the inability of readers to make meaningful comparisons across published studies have greatly contributed to skepticism about the validity, reliability, and relevance of these studies to healthcare decision-makers. Using a case study in the field of lipid PE, two suggestions are presented for generally applicable reporting standards that will improve the credibility of PE. Health economists and researchers should be expected to provide either the software used to create their PE model or a multivariate sensitivity analysis of their PE model. Software distribution would allow other users to validate the assumptions and calculations of a particular model and apply it to their own circumstances. Multivariate sensitivity analysis can also be used to present results in a consistent and meaningful way that will facilitate comparisons across the PE literature. Using these methods, broader acceptance and application of PE results by policy-makers would become possible. To reduce the uncertainty about what is being accomplished with PE studies, it is recommended that these guidelines become requirements of both scientific journals and healthcare plan decision-makers. The standardization of economic modeling in this manner will increase the acceptability of pharmacoeconomics as a practical, real-world science.

  3. Ethanol production: energy, economic, and environmental losses.

    PubMed

    Pimentel, David; Patzek, Tad; Cecil, Gerald

    2007-01-01

    The prime focus of ethanol production from corn is to replace the imported oil used in American vehicles, without expending more fossil energy in ethanol production than is produced as ethanol energy. In a thorough and up-to-date evaluation of all the fossil energy costs of ethanol production from corn, every step in the production and conversion process must be included. In this study, 14 energy inputs in average U.S. corn production are included. Then, in the fermentation/distillation operation, 9 more identified fossil fuel inputs are included. Some energy and economic credits are given for the by-products, including dried distillers grains (DDG). Based on all the fossil energy inputs, a total of 1.43 kcal fossil energy is expended to produced 1 kcal ethanol. When the energy value of the DDG, based on the feed value of the DDG as compared to that of soybean meal, is considered, the energy cost of ethanol production is reduced slightly, to 1.28 kcal fossil energy input per 1 kcal ethanol produced. Several proethanol investigators have overlooked various energy inputs in U.S. corn production, including farm machinery, processing machinery, and the use of hybrid corn. In other studies, unrealistic, low energy costs were attributed to such inputs as nitrogen fertilizer, insecticides, and herbicides. Controversy continues concerning the energy and economic credits that should be assigned to the by-products. The U.S. Department of Energy reports that 17.0 billion L ethanol was produced in 2005. This represents only less than 1% of total oil use in the U.S. These yields are based on using about 18% of total U.S. corn production and 18% of cornland. Because the production of ethanol requires large inputs of both oil and natural gas in production, the U.S. is importing both oil and natural gas to produce ethanol. Furthermore, the U.S. Government is spending about dollar 3 billion annually to subsidize ethanol production, a subsidy of dollar 0.79/L ethanol produced. With

  4. Economic aspects of amino acids production.

    PubMed

    Mueller, Udo; Huebner, Susanna

    2003-01-01

    Amino acids represent basic elements of proteins, which as a main source of nutrition themselves serve as a major reserve for maintaining essential functions of humans as well as animals. Taking the recent state of scientific knowledge into account, the industrial sector of amino acids is a priori "suitable" to a specific kind of an ecologically sound way of production, which is based on biotechnology. The following article may point out characteristics of this particular industrial sector and illustrates the applicability of the latest economic methods, founded on development of the discipline of bionics in order to describe economic aspects of amino acids markets. The several biochemical and technological fields of application of amino acids lead to specific market structures in high developed and permanently evolving systems. The Harvard tradition of industrial economics explains how market structures mould the behaviour of the participants and influences market results beyond that. A global increase in intensity of competition confirms the notion that the supply-side is characterised by asymmetric information in contrast to Kantzenbachs concept of "narrow oligopoly" with symmetrical shared knowledge about market information. Departing from this point, certain strategies of companies in this market form shall be derived. The importance of Research and Development increases rapidly and leads to innovative manufacturing methods which replace more polluting manufacturing processes like acid hydrolysis. In addition to these modifications within the production processes the article deals furthermore with the pricing based on product life cycle concept and introduces specific applications of tools like activity based costing and target costing to the field of amino acid production. The authors come to the conclusion that based on a good transferability of latest findings in bionics and ecological compatibility competitors in amino acids manufacturing are well advised

  5. HOMER Economic Models - US Navy

    SciTech Connect

    Bush, Jason William; Myers, Kurt Steven

    2016-02-01

    This LETTER REPORT has been prepared by Idaho National Laboratory for US Navy NAVFAC EXWC to support in testing pre-commercial SIREN (Simulated Integration of Renewable Energy Networks) computer software models. In the logistics mode SIREN software simulates the combination of renewable power sources (solar arrays, wind turbines, and energy storage systems) in supplying an electrical demand. NAVFAC EXWC will create SIREN software logistics models of existing or planned renewable energy projects at five Navy locations (San Nicolas Island, AUTEC, New London, & China Lake), and INL will deliver additional HOMER computer models for comparative analysis. In the transient mode SIREN simulates the short time-scale variation of electrical parameters when a power outage or other destabilizing event occurs. In the HOMER model, a variety of inputs are entered such as location coordinates, Generators, PV arrays, Wind Turbines, Batteries, Converters, Grid costs/usage, Solar resources, Wind resources, Temperatures, Fuels, and Electric Loads. HOMER's optimization and sensitivity analysis algorithms then evaluate the economic and technical feasibility of these technology options and account for variations in technology costs, electric load, and energy resource availability. The Navy can then use HOMER’s optimization and sensitivity results to compare to those of the SIREN model. The U.S. Department of Energy (DOE) Idaho National Laboratory (INL) possesses unique expertise and experience in the software, hardware, and systems design for the integration of renewable energy into the electrical grid. NAVFAC EXWC will draw upon this expertise to complete mission requirements.

  6. Scleroglucan biopolymer production, properties, and economics

    SciTech Connect

    Compere, A. L.; Griffith, W. L.

    1980-01-01

    Production and solution properties which may make scleroglucan polysaccharide economically advantageous for onsite production and use in tertiary oil recovery were investigated. Scleroglucan, which is similar in viscosity and shear thinning to xanthan, can be produced in a 3-day batch or 12 h continuous fermentation. Yield is nearly 50% based on input glucose. Gross biopolymer-biomass separation may be effected using microscreening, a low energy process, followed by polish filtration. Polymer flux may be improved by hydrolysis with an endolaminarinase from Rhizopus arrhizius QM 1032. Simple feedstock requirements and low growth pH, together with the difficulty of resuspending dried polymer, may encourage field biopolymer fermentation and use of purified culture broth.

  7. Coupling Climate Models and Forward-Looking Economic Models

    NASA Astrophysics Data System (ADS)

    Judd, K.; Brock, W. A.

    2010-12-01

    Authors: Dr. Kenneth L. Judd, Hoover Institution, and Prof. William A. Brock, University of Wisconsin Current climate models range from General Circulation Models (GCM’s) with millions of degrees of freedom to models with few degrees of freedom. Simple Energy Balance Climate Models (EBCM’s) help us understand the dynamics of GCM’s. The same is true in economics with Computable General Equilibrium Models (CGE’s) where some models are infinite-dimensional multidimensional differential equations but some are simple models. Nordhaus (2007, 2010) couples a simple EBCM with a simple economic model. One- and two- dimensional ECBM’s do better at approximating damages across the globe and positive and negative feedbacks from anthroprogenic forcing (North etal. (1981), Wu and North (2007)). A proper coupling of climate and economic systems is crucial for arriving at effective policies. Brock and Xepapadeas (2010) have used Fourier/Legendre based expansions to study the shape of socially optimal carbon taxes over time at the planetary level in the face of damages caused by polar ice cap melt (as discussed by Oppenheimer, 2005) but in only a “one dimensional” EBCM. Economists have used orthogonal polynomial expansions to solve dynamic, forward-looking economic models (Judd, 1992, 1998). This presentation will couple EBCM climate models with basic forward-looking economic models, and examine the effectiveness and scaling properties of alternative solution methods. We will use a two dimensional EBCM model on the sphere (Wu and North, 2007) and a multicountry, multisector regional model of the economic system. Our aim will be to gain insights into intertemporal shape of the optimal carbon tax schedule, and its impact on global food production, as modeled by Golub and Hertel (2009). We will initially have limited computing resources and will need to focus on highly aggregated models. However, this will be more complex than existing models with forward

  8. Economic analysis of HPAI control in the Netherlands I: epidemiological modelling to support economic analysis.

    PubMed

    Longworth, N; Mourits, M C M; Saatkamp, H W

    2014-06-01

    Economic analysis of control strategies for contagious diseases is a necessity in the development of contingency plans. Economic impacts arising from epidemics such as highly pathogenic avian influenza (HPAI) consist of direct costs (DC), direct consequential costs (DCC), indirect consequential costs (ICC) and aftermath costs (AC). Epidemiological models to support economic analysis need to provide adequate outputs for these critical economic parameters. Of particular importance for DCC, ICC and AC is the spatial production structure of a region. Spatial simulation models are therefore particularly suited for economic analysis; however, they often require a large number of parameters. The aims of this study are (i) to provide an economic rationale of epidemiological modelling in general, (ii) to provide a transparent description of the parameterization of a spatially based epidemiological model for the analysis of HPAI control in the Netherlands and (iii) to discuss the validity and usefulness of this model for subsequent economic analysis. In the model, HPAI virus transmission occurs via local spread and animal movements. Control mechanisms include surveillance and tracing, movement restrictions and depopulation. Sensitivity analysis of key parameters indicated that the epidemiological outputs with the largest influence on the economic impacts (i.e. epidemic duration and number of farms in the movement restriction zone) were more robust than less influential indicators (i.e. number of infected farms). Economically relevant outputs for strategy comparison were most sensitive to the relative role of the different transmission parameters. The default simulation and results of the sensitivity analysis were consistent with the general outcomes of known HPAI models. Comparison was, however, limited due to the absence of some economically relevant outputs. It was concluded that the model creates economically relevant, adequate and credible output for subsequent use in

  9. Teaching Economics: A Cooperative Learning Model.

    ERIC Educational Resources Information Center

    Caropreso, Edward J.; Haggerty, Mark

    2000-01-01

    Describes an alternative approach to introductory economics based on a cooperative learning model, "Learning Together." Discussion of issues in economics education and cooperative learning in higher education leads to explanation of how to adapt the Learning Together Model to lesson planning in economics. A flow chart illustrates the process for a…

  10. Economic values of production and functional traits, including residual feed intake, in Finnish milk production.

    PubMed

    Hietala, P; Wolfová, M; Wolf, J; Kantanen, J; Juga, J

    2014-02-01

    Improving the feed efficiency of dairy cattle has a substantial effect on the economic efficiency and on the reduction of harmful environmental effects of dairy production through lower feeding costs and emissions from dairy farming. To assess the economic importance of feed efficiency in the breeding goal for dairy cattle, the economic values for the current breeding goal traits and the additional feed efficiency traits for Finnish Ayrshire cattle under production circumstances in 2011 were determined. The derivation of economic values was based on a bioeconomic model in which the profit of the production system was calculated, using the generated steady state herd structure. Considering beef production from dairy farms, 2 marketing strategies for surplus calves were investigated: (A) surplus calves were sold at a young age and (B) surplus calves were fattened on dairy farms. Both marketing strategies were unprofitable when subsidies were not included in the revenues. When subsidies were taken into account, a positive profitability was observed in both marketing strategies. The marginal economic values for residual feed intake (RFI) of breeding heifers and cows were -25.5 and -55.8 €/kg of dry matter per day per cow and year, respectively. The marginal economic value for RFI of animals in fattening was -29.5 €/kg of dry matter per day per cow and year. To compare the economic importance among traits, the standardized economic weight of each trait was calculated as the product of the marginal economic value and the genetic standard deviation; the standardized economic weight expressed as a percentage of the sum of all standardized economic weights was called relative economic weight. When not accounting for subsidies, the highest relative economic weight was found for 305-d milk yield (34% in strategy A and 29% in strategy B), which was followed by protein percentage (13% in strategy A and 11% in strategy B). The third most important traits were calving

  11. Preliminary Economics for Hydrocarbon Fuel Production from Cellulosic Sugars

    SciTech Connect

    Collett, James R.; Meyer, Pimphan A.; Jones, Susanne B.

    2014-05-18

    Biorefinery process and economic models built in CHEMCAD and a preliminary, genome-scale metabolic model for the oleaginous yeast Lipomyces starkeyi were used to simulate the bioconversion of corn stover to lipids, and the upgrading of these hydrocarbon precursors to diesel and jet fuel. The metabolic model was based on the recently released genome sequence for L. starkeyi and on metabolic pathway information from the literature. The process model was based on bioconversion, lipid extraction, and lipid oil upgrading data found in literature, on new laboratory experimental data, and on yield predictions from the preliminary L. starkeyi metabolic model. The current plant gate production cost for a distillate-range hydrocarbon fuel was estimated by the process model Base Case to be $9.5/gallon ($9.0 /gallon of gasoline equivalent) with assumptions of 2011$, 10% internal return on investment, and 2205 ton/day dry feed rate. Opportunities for reducing the cost to below $5.0/gallon, such as improving bioconversion lipid yield and hydrogenation catalyst selectivity, are presented in a Target Case. The process and economic models developed for this work will be updated in 2014 with new experimental data and predictions from a refined metabolic network model for L. starkeyi. Attaining a production cost of $3.0/gallon will require finding higher value uses for lignin other than power generation, such as conversion to additional fuel or to a co-product.

  12. Thermodynamics and economic feasibility of acetone production from syngas using the thermophilic production host Moorella thermoacetica.

    PubMed

    Redl, Stephanie; Sukumara, Sumesh; Ploeger, Tom; Wu, Liang; Ølshøj Jensen, Torbjørn; Nielsen, Alex Toftgaard; Noorman, Henk

    2017-01-01

    Syngas fermentation is a promising option for the production of biocommodities due to its abundance and compatibility with anaerobic fermentation. Using thermophilic production strains in a syngas fermentation process allows recovery of products with low boiling point from the off-gas via condensation. In this study we analyzed the production of acetone from syngas with the hypothetical production host derived from Moorella thermoacetica in a bubble column reactor at 60 °C with respect to thermodynamic and economic feasibility. We determined the cost of syngas production from basic oxygen furnace (BOF) process gas, from natural gas, and from corn stover and identified BOF gas as an economically interesting source for syngas. Taking gas-liquid mass transfer limitations into account, we applied a thermodynamics approach to derive the CO to acetone conversion rate under the process conditions. We estimated variable costs of production of 389 $/t acetone for a representative production scenario from BOF gas with costs for syngas as the main contributor. In comparison, the variable costs of production from natural gas- and corn stover-derived syngas were determined to be higher due to the higher feedstock costs (1724 and 2878 $/t acetone, respectively). We applied an approach of combining thermodynamic and economic assessment to analyze a hypothetical bioprocess in which the volatile product acetone is produced from syngas with a thermophilic microorganism. Our model allowed us to identify process metrics and quantify the variable production costs for different scenarios. Economical production of bulk chemicals is challenging, making rigorous thermodynamic/economic modeling critical before undertaking an experimental program and as an ongoing guide during the program. We intend this study to give an incentive to apply the demonstrated approach to other bioproduction processes.

  13. Economic lot sizing in a production system with random demand

    NASA Astrophysics Data System (ADS)

    Lee, Shine-Der; Yang, Chin-Ming; Lan, Shu-Chuan

    2016-04-01

    An extended economic production quantity model that copes with random demand is developed in this paper. A unique feature of the proposed study is the consideration of transient shortage during the production stage, which has not been explicitly analysed in existing literature. The considered costs include set-up cost for the batch production, inventory carrying cost during the production and depletion stages in one replenishment cycle, and shortage cost when demand cannot be satisfied from the shop floor immediately. Based on renewal reward process, a per-unit-time expected cost model is developed and analysed. Under some mild condition, it can be shown that the approximate cost function is convex. Computational experiments have demonstrated that the average reduction in total cost is significant when the proposed lot sizing policy is compared with those with deterministic demand.

  14. Drilling and production - Economics show CO2 EOR potential

    USGS Publications Warehouse

    Dubois, M.K.; Byrnes, A.P.

    2000-01-01

    CO2 EOR may be the key to recovering hundreds of millions of bbl of trapped oil from the mature fields in central Kansas. A simple model aided in assessing the economics of CO2 EOR for central Kansas and the Midcontinent. The model used CO2 Prophet, a DOE freeware reservoir numerical simulation program, to determine reservoir performance, including injected and produced fluid rates, and CO2 utilization. Economic parameters, e.g., oil price, CO2 costs, capital costs, net revenue interest, production taxes, and lease operating expenses, are typical for anticipated conditions in the region and present price climate. Preliminary economic analysis shows that CO2 EOR should give an internal rate of return (IRR) > 20%, before income tax, assuming oil sells for $20/bbl, CO2 costs $1/million cu ft, and gross utilization is 10 million cu ft of CO2/bbl of oil recovered. If the CO2 is reduced to $0.75/million cu ft, an oil price of $17/bbl yields an IRR of 20%. Reservoir and economic modeling shows that IRR is most sensitive to oil price and CO2 cost.

  15. Economic tour package model using heuristic

    NASA Astrophysics Data System (ADS)

    Rahman, Syariza Abdul; Benjamin, Aida Mauziah; Bakar, Engku Muhammad Nazri Engku Abu

    2014-07-01

    A tour-package is a prearranged tour that includes products and services such as food, activities, accommodation, and transportation, which are sold at a single price. Since the competitiveness within tourism industry is very high, many of the tour agents try to provide attractive tour-packages in order to meet tourist satisfaction as much as possible. Some of the criteria that are considered by the tourist are the number of places to be visited and the cost of the tour-packages. Previous studies indicate that tourists tend to choose economical tour-packages and aiming to visit as many places as they can cover. Thus, this study proposed tour-package model using heuristic approach. The aim is to find economical tour-packages and at the same time to propose as many places as possible to be visited by tourist in a given geographical area particularly in Langkawi Island. The proposed model considers only one starting point where the tour starts and ends at an identified hotel. This study covers 31 most attractive places in Langkawi Island from various categories of tourist attractions. Besides, the allocation of period for lunch and dinner are included in the proposed itineraries where it covers 11 popular restaurants around Langkawi Island. In developing the itinerary, the proposed heuristic approach considers time window for each site (hotel/restaurant/place) so that it represents real world implementation. We present three itineraries with different time constraints (1-day, 2-day and 3-day tour-package). The aim of economic model is to minimize the tour-package cost as much as possible by considering entrance fee of each visited place. We compare the proposed model with our uneconomic model from our previous study. The uneconomic model has no limitation to the cost with the aim to maximize the number of places to be visited. Comparison between the uneconomic and economic itinerary has shown that the proposed model have successfully achieved the objective that

  16. Global non-linear effect of temperature on economic production

    NASA Astrophysics Data System (ADS)

    Burke, Marshall; Hsiang, Solomon M.; Miguel, Edward

    2015-11-01

    Growing evidence demonstrates that climatic conditions can have a profound impact on the functioning of modern human societies, but effects on economic activity appear inconsistent. Fundamental productive elements of modern economies, such as workers and crops, exhibit highly non-linear responses to local temperature even in wealthy countries. In contrast, aggregate macroeconomic productivity of entire wealthy countries is reported not to respond to temperature, while poor countries respond only linearly. Resolving this conflict between micro and macro observations is critical to understanding the role of wealth in coupled human-natural systems and to anticipating the global impact of climate change. Here we unify these seemingly contradictory results by accounting for non-linearity at the macro scale. We show that overall economic productivity is non-linear in temperature for all countries, with productivity peaking at an annual average temperature of 13 °C and declining strongly at higher temperatures. The relationship is globally generalizable, unchanged since 1960, and apparent for agricultural and non-agricultural activity in both rich and poor countries. These results provide the first evidence that economic activity in all regions is coupled to the global climate and establish a new empirical foundation for modelling economic loss in response to climate change, with important implications. If future adaptation mimics past adaptation, unmitigated warming is expected to reshape the global economy by reducing average global incomes roughly 23% by 2100 and widening global income inequality, relative to scenarios without climate change. In contrast to prior estimates, expected global losses are approximately linear in global mean temperature, with median losses many times larger than leading models indicate.

  17. Global non-linear effect of temperature on economic production.

    PubMed

    Burke, Marshall; Hsiang, Solomon M; Miguel, Edward

    2015-11-12

    Growing evidence demonstrates that climatic conditions can have a profound impact on the functioning of modern human societies, but effects on economic activity appear inconsistent. Fundamental productive elements of modern economies, such as workers and crops, exhibit highly non-linear responses to local temperature even in wealthy countries. In contrast, aggregate macroeconomic productivity of entire wealthy countries is reported not to respond to temperature, while poor countries respond only linearly. Resolving this conflict between micro and macro observations is critical to understanding the role of wealth in coupled human-natural systems and to anticipating the global impact of climate change. Here we unify these seemingly contradictory results by accounting for non-linearity at the macro scale. We show that overall economic productivity is non-linear in temperature for all countries, with productivity peaking at an annual average temperature of 13 °C and declining strongly at higher temperatures. The relationship is globally generalizable, unchanged since 1960, and apparent for agricultural and non-agricultural activity in both rich and poor countries. These results provide the first evidence that economic activity in all regions is coupled to the global climate and establish a new empirical foundation for modelling economic loss in response to climate change, with important implications. If future adaptation mimics past adaptation, unmitigated warming is expected to reshape the global economy by reducing average global incomes roughly 23% by 2100 and widening global income inequality, relative to scenarios without climate change. In contrast to prior estimates, expected global losses are approximately linear in global mean temperature, with median losses many times larger than leading models indicate.

  18. Computerized Economic Modeling: From Laboratory to Classroom.

    ERIC Educational Resources Information Center

    Breece, James H.

    1988-01-01

    Investigates the growing popularity of computerized economic modeling as a computer-assisted instructional aid and the associated educational benefits. Provides an overview of current modeling, simulation, and econometrics programs and attempts to identify trends in computer-assisted instruction in economics. (Author/GEA)

  19. Projecting global tropical cyclone economic damages with validation of tropical cyclone economic damage model

    NASA Astrophysics Data System (ADS)

    Iseri, Y.; Iwasaki, A.; Miyazaki, C.; Kanae, S.

    2014-12-01

    Tropical cyclones (TCs) sometimes cause serious damages to human society and thus possible changes of TC properties in the future have been concerned. In fact, the Fifth Assessment Report (AR5) by IPCC (Intergovernmental Panel on Climate Change) mentions likely increasing in intensity and rain rate of TCs. In addition, future change of socioeconomic condition (e.g. population growth) might worsen TC impacts in the future. Thereby, in this study, we developed regression models to estimate economic damages by TCs (hereafter TC damage model), and employed those models to project TC economic damages under several future climate and socioeconomic scenarios. We developed the TC damage models for each of 4 regions; western North Pacific, North American, North Indian, and Southern Hemisphere. The inputs for TC damage model are tropical cyclone central pressure, populations in the area exposed by tropical cyclone wind, and GDP (Gross Domestic Product) per capita. The TC damage models we firstly developed tended to overestimate very low damages and also underestimate very high damages. Thereby we modified structure of TC damage models to improve model performance, and then executed extensive validation of the model. The modified model presented better performance in estimating very low and high TC damages. After the modification and validation of the model, we determined the structure of TC damage models and projected TC economic damages. The result indicated increase in TC economic damage in global scale, while TC economic damage against world GDP would decrease in the future, which result is consistent with previous study.

  20. Economic assessment of biodiesel production from waste frying oils.

    PubMed

    Araujo, Victor Kraemer Wermelinger Sancho; Hamacher, Silvio; Scavarda, Luiz Felipe

    2010-06-01

    Waste frying oils (WFO) can be a good source for the production of biodiesel because this raw material is not part of the food chain, is low cost and can be used in a way that resolves environmental problems (i.e. WFO is no longer thrown into the sewage network). The goal of this article is to propose a method to evaluate the costs of biodiesel production from WFO to develop an economic assessment of this alternative. This method embraces a logistics perspective, as the cost of collection of oil from commercial producers and its delivery to biodiesel depots or plants can be relevant and is an issue that has been little explored in the academic literature. To determine the logistics cost, a mathematical programming model is proposed to solve the vehicle routing problem (VRP), which was applied in an important urban center in Brazil (Rio de Janeiro), a relevant and potential center for biodiesel production and consumption. Eighty-one biodiesel cost scenarios were compared with information on the commercialization of biodiesel in Brazil. The results obtained demonstrate the economic viability of biodiesel production from WFO in the urban center studied and the relevance of logistics in the total biodiesel production cost. (c) 2010 Elsevier Ltd. All rights reserved.

  1. HTGR Application Economic Model Users' Manual

    SciTech Connect

    A.M. Gandrik

    2012-01-01

    The High Temperature Gas-Cooled Reactor (HTGR) Application Economic Model was developed at the Idaho National Laboratory for the Next Generation Nuclear Plant Project. The HTGR Application Economic Model calculates either the required selling price of power and/or heat for a given internal rate of return (IRR) or the IRR for power and/or heat being sold at the market price. The user can generate these economic results for a range of reactor outlet temperatures; with and without power cycles, including either a Brayton or Rankine cycle; for the demonstration plant, first of a kind, or nth of a kind project phases; for up to 16 reactor modules; and for module ratings of 200, 350, or 600 MWt. This users manual contains the mathematical models and operating instructions for the HTGR Application Economic Model. Instructions, screenshots, and examples are provided to guide the user through the HTGR Application Economic Model. This model was designed for users who are familiar with the HTGR design and Excel and engineering economics. Modification of the HTGR Application Economic Model should only be performed by users familiar with the HTGR and its applications, Excel, and Visual Basic.

  2. Economics. Does science drive the productivity train?

    PubMed

    Malakoff, D

    2000-08-25

    From the president on down, many are hailing science as the fuel for today's booming economy, and bigger research budgets are seen as essential to continued prosperity. But skeptics say the information technology revolution is overrated as a contributor to economic growth when compared to the truly society-shaking innovations of the past, such as electricity or the telephone. Even some science lobbyists worry that hitching basic research's star too closely to economic arguments could backfire, prompting legislators to take a firmer hand in guiding cash toward less risky projects that they believe will pay off big.

  3. Techno-Economic Analysis of Biofuels Production Based on Gasification

    SciTech Connect

    Swanson, R. M.; Platon, A.; Satrio, J. A.; Brown, R. C.; Hsu, D. D.

    2010-11-01

    This study compares capital and production costs of two biomass-to-liquid production plants based on gasification. The first biorefinery scenario is an oxygen-fed, low-temperature (870?C), non-slagging, fluidized bed gasifier. The second scenario is an oxygen-fed, high-temperature (1,300?C), slagging, entrained flow gasifier. Both are followed by catalytic Fischer-Tropsch synthesis and hydroprocessing to naphtha-range (gasoline blend stock) and distillate-range (diesel blend stock) liquid fractions. Process modeling software (Aspen Plus) is utilized to organize the mass and energy streams and cost estimation software is used to generate equipment costs. Economic analysis is performed to estimate the capital investment and operating costs. Results show that the total capital investment required for nth plant scenarios is $610 million and $500 million for high-temperature and low-temperature scenarios, respectively. Product value (PV) for the high-temperature and low-temperature scenarios is estimated to be $4.30 and $4.80 per gallon of gasoline equivalent (GGE), respectively, based on a feedstock cost of $75 per dry short ton. Sensitivity analysis is also performed on process and economic parameters. This analysis shows that total capital investment and feedstock cost are among the most influential parameters affecting the PV.

  4. Economic development and the allocation of petroleum products in Sudan

    SciTech Connect

    Cain, M. ); Yousif, M.A.R. )

    1991-01-01

    The Sudanese economy has been characterized in recent years by severe energy shortages which have affected all economic activity. More than 94% of the commercial energy is imported and the level of such imports is seriously limited by the current foreign exchange crisis. However, the problem is not just one of foreign exchange; there is also the problem of utilization of resources to avoid bottleneck problems of supply. The allocation of petroleum products in Sudan has had a severe effect on all aspects of economic life. The aim of this paper is to highlight the problem and to build a model to optimize the distribution of petroleum products in order to achieve at least a minimal supply in all regions. A large linear programming model has been developed and the solution indicates that current facilities should be able to satisfy 96% of the 1986 demand, about 30% more than the actual supply. Furthermore, with a little investment in storage facilities and extra trucks, the supply could satisfy total demand in the immediate future.

  5. "Economic microscope": The agent-based model set as an instrument in an economic system research

    NASA Astrophysics Data System (ADS)

    Berg, D. B.; Zvereva, O. M.; Akenov, Serik

    2017-07-01

    To create a valid model of a social or economic system one must consider a lot of parameters, conditions and restrictions. Systems and, consequently, the corresponding models are proved to be very complicated. The problem of such system model engineering can't be solved only with mathematical methods usage. The decision could be found in computer simulation. Simulation does not reject mathematical methods, mathematical expressions could become the foundation for a computer model. In these materials the set of agent-based computer models is under discussion. All the set models simulate productive agents communications, but every model is geared towards the specific goal, and, thus, has its own algorithm and its own peculiarities. It is shown that computer simulation can discover new features of the agents' behavior that can not be obtained by analytical solvation of mathematical equations and thus plays the role of some kind of economic microscope.

  6. Moving forward socio-economically focused models of deforestation.

    PubMed

    Dezécache, Camille; Salles, Jean-Michel; Vieilledent, Ghislain; Hérault, Bruno

    2017-01-05

    Whilst high-resolution spatial variables contribute to a good fit of spatially explicit deforestation models, socio-economic processes are often beyond the scope of these models. Such a low level of interest in the socio-economic dimension of deforestation limits the relevancy of these models for decision-making and may be the cause of their failure to accurately predict observed deforestation trends in the medium term. This study aims to propose a flexible methodology for taking into account multiple drivers of deforestation in tropical forested areas, where the intensity of deforestation is explicitly predicted based on socio-economic variables. By coupling a model of deforestation location based on spatial environmental variables with several sub-models of deforestation intensity based on socio-economic variables, we were able to create a map of predicted deforestation over the period 2001-2014 in French Guiana. This map was compared to a reference map for accuracy assessment, not only at the pixel scale but also over cells ranging from 1 to approximately 600 sq. km. Highly significant relationships were explicitly established between deforestation intensity and several socio-economic variables: population growth, the amount of agricultural subsidies, gold and wood production. Such a precise characterization of socio-economic processes allows to avoid overestimation biases in high deforestation areas, suggesting a better integration of socio-economic processes in the models. Whilst considering deforestation as a purely geographical process contributes to the creation of conservative models unable to effectively assess changes in the socio-economic and political contexts influencing deforestation trends, this explicit characterization of the socio-economic dimension of deforestation is critical for the creation of deforestation scenarios in REDD+ projects.

  7. How to estimate productivity costs in economic evaluations.

    PubMed

    Krol, Marieke; Brouwer, Werner

    2014-04-01

    Productivity costs are frequently omitted from economic evaluations, despite their often strong impact on cost-effectiveness outcomes. This neglect may be partly explained by the lack of standardization regarding the methodology of estimating productivity costs. This paper aims to contribute to standardization of productivity cost methodology by offering practical guidance on how to estimate productivity costs in economic evaluations. The paper discusses the identification, measurement and valuation of productivity losses. It is recommended to include not only productivity losses related to absenteeism from and reduced productivity at paid work, but also those related to unpaid work. Hence, it is recommended to use a measurement instrument including questions about both paid and unpaid productivity, such as the iMTA Productivity Cost Questionnaire (iPCQ) or the Valuation of Lost Productivity (VOLP). We indicate how to apply the friction cost and the human capital approach and give practical guidance on deriving final cost estimates.

  8. The Commercialisation of University Research and Economic Productivity

    ERIC Educational Resources Information Center

    Clark, Paul

    2007-01-01

    This article focuses on the relationship between university research (in this case science research) and national economic productivity, particularly in the context of the emerging knowledge economy. It addresses the question of whether university research output should be treated as a public good or a private good, in economic terms, and analyses…

  9. Microalgae production: technical and economic evaluations.

    PubMed

    Tapie, P; Bernard, A

    1988-09-20

    A review of the various literature data for large-scale algae production costs is described. Costs were updated and recomputed in order to compare the different schemes. Total production costs of a nonprocessed biomass range from US$0.15 to US$4.0 kg(-1), according to various authors. Process performance hypotheses and proposed technologies are analyzed to explain these variations. A cost analysis for a tubular bioreactor system is then presented that shows that, assuming a productivity of 60 tons/ha yr, production costs would range from FF24 to FF29 kg(-1) for such a system. Operating costs as well as fixed charges account for approximately 50% of the cost. Parametric sensitivity of these costs is then analyzed: If productivity would be 30, 45, or 90 tons/ha yr, total cost would be around FF48, FF33 and FF19 kg(-1). Advantages and disadvantages of the proposed tubular technology are finally discussed.

  10. Techno-economic and Monte Carlo probabilistic analysis of microalgae biofuel production system.

    PubMed

    Batan, Liaw Y; Graff, Gregory D; Bradley, Thomas H

    2016-11-01

    This study focuses on the characterization of the technical and economic feasibility of an enclosed photobioreactor microalgae system with annual production of 37.85 million liters (10 million gallons) of biofuel. The analysis characterizes and breaks down the capital investment and operating costs and the production cost of unit of algal diesel. The economic modelling shows total cost of production of algal raw oil and diesel of $3.46 and $3.69 per liter, respectively. Additionally, the effects of co-products' credit and their impact in the economic performance of algal-to-biofuel system are discussed. The Monte Carlo methodology is used to address price and cost projections and to simulate scenarios with probabilities of financial performance and profits of the analyzed model. Different markets for allocation of co-products have shown significant shifts for economic viability of algal biofuel system. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Temperatures and cyclones strongly associated with economic production in the Caribbean and Central America.

    PubMed

    Hsiang, Solomon M

    2010-08-31

    Understanding the economic impact of surface temperatures is an important question for both economic development and climate change policy. This study shows that in 28 Caribbean-basin countries, the response of economic output to increased temperatures is structurally similar to the response of labor productivity to high temperatures, a mechanism omitted from economic models of future climate change. This similarity is demonstrated by isolating the direct influence of temperature from that of tropical cyclones, an important correlate. Notably, output losses occurring in nonagricultural production (-2.4%/+1 degrees C) substantially exceed losses occurring in agricultural production (-0.1%/+1 degrees C). Thus, these results suggest that current models of future climate change that focus on agricultural impacts but omit the response of workers to thermal stress may underestimate the global economic costs of climate change.

  12. Temperatures and cyclones strongly associated with economic production in the Caribbean and Central America

    PubMed Central

    Hsiang, Solomon M.

    2010-01-01

    Understanding the economic impact of surface temperatures is an important question for both economic development and climate change policy. This study shows that in 28 Caribbean-basin countries, the response of economic output to increased temperatures is structurally similar to the response of labor productivity to high temperatures, a mechanism omitted from economic models of future climate change. This similarity is demonstrated by isolating the direct influence of temperature from that of tropical cyclones, an important correlate. Notably, output losses occurring in nonagricultural production (–2.4%/+1 °C) substantially exceed losses occurring in agricultural production (–0.1%/+1 °C). Thus, these results suggest that current models of future climate change that focus on agricultural impacts but omit the response of workers to thermal stress may underestimate the global economic costs of climate change. PMID:20713696

  13. Productivity costs in economic evaluations: past, present, future.

    PubMed

    Krol, Marieke; Brouwer, Werner; Rutten, Frans

    2013-07-01

    Productivity costs occur when the productivity of individuals is affected by illness, treatment, disability or premature death. The objective of this paper was to review past and current developments related to the inclusion, identification, measurement and valuation of productivity costs in economic evaluations. The main debates in the theory and practice of economic evaluations of health technologies described in this review have centred on the questions of whether and how to include productivity costs, especially productivity costs related to paid work. The past few decades have seen important progress in this area. There are important sources of productivity costs other than absenteeism (e.g. presenteeism and multiplier effects in co-workers), but their exact influence on costs remains unclear. Different measurement instruments have been developed over the years, but which instrument provides the most accurate estimates has not been established. Several valuation approaches have been proposed. While empirical research suggests that productivity costs are best included in the cost side of the cost-effectiveness ratio, the jury is still out regarding whether the human capital approach or the friction cost approach is the most appropriate valuation method to do so. Despite the progress and the substantial amount of scientific research, a consensus has not been reached on either the inclusion of productivity costs in economic evaluations or the methods used to produce productivity cost estimates. Such a lack of consensus has likely contributed to ignoring productivity costs in actual economic evaluations and is reflected in variations in national health economic guidelines. Further research is needed to lessen the controversy regarding the estimation of health-related productivity costs. More standardization would increase the comparability and credibility of economic evaluations taking a societal perspective.

  14. Agent-based modeling in ecological economics.

    PubMed

    Heckbert, Scott; Baynes, Tim; Reeson, Andrew

    2010-01-01

    Interconnected social and environmental systems are the domain of ecological economics, and models can be used to explore feedbacks and adaptations inherent in these systems. Agent-based modeling (ABM) represents autonomous entities, each with dynamic behavior and heterogeneous characteristics. Agents interact with each other and their environment, resulting in emergent outcomes at the macroscale that can be used to quantitatively analyze complex systems. ABM is contributing to research questions in ecological economics in the areas of natural resource management and land-use change, urban systems modeling, market dynamics, changes in consumer attitudes, innovation, and diffusion of technology and management practices, commons dilemmas and self-governance, and psychological aspects to human decision making and behavior change. Frontiers for ABM research in ecological economics involve advancing the empirical calibration and validation of models through mixed methods, including surveys, interviews, participatory modeling, and, notably, experimental economics to test specific decision-making hypotheses. Linking ABM with other modeling techniques at the level of emergent properties will further advance efforts to understand dynamics of social-environmental systems.

  15. Liquid hydrogen production and economics for NASA Kennedy Space Center

    NASA Astrophysics Data System (ADS)

    Block, D. L.

    1985-12-01

    Detailed economic analyses for the production of liquid hydrogen used to power the Space Shuttle are presented. The hydrogen production and energy needs of the NASA Kennedy Space Center are reviewed, and steam reformation, polygeneration, and electrolysis for liquid hydrogen production are examined on an equal economic basis. The use of photovoltaics as an electrolysis power source is considered. The 1985 present worth is calculated based on life cycle costs over a 21-year period beginning with full operation in 1990. Two different sets of escalation, inflation, and discount rates are used, with revenue credit being given for energy or other products of the hydrogen production process. The results show that the economic analyses are very dependent on the escalation rates used. The least net present value is found for steam reformation of natural gas, while the best net present value is found for the electrolysis process which includes the phasing of photovoltaics.

  16. Understanding and modeling the economics of ECM

    NASA Astrophysics Data System (ADS)

    Wells, Wayne E.; Edinbarough, Immanuel A.

    2004-12-01

    Traditional economic analysis methods for manufacturing decisions include only the clearly identified immediate cost and revenue streams. Environmental issues have generally been seen as costs, in the form of waste material losses, conformance tests and pre-discharge treatments. The components of the waste stream often purchased as raw materials, become liabilities at the "end of the pipe" and their intrinsic material value is seldom recognized. A new mathematical treatment of manufacturing economics is proposed in which the costs of separation are compared with the intrinsic value of the waste materials to show how their recovery can provide an economic advantage to the manufacturer. The model is based on a unique combination of thermodynamic analysis, economic modeling and linear optimization. This paper describes the proposed model, and examines case studies in which the changed decision rules have yielded significant savings while protecting the environment. The premise proposed is that by including the value of the waste materials in the profit objective of the firm and applying the appropriate technological solution, manufacturing processes can become closed systems in which losses approach zero and environmental problems are converted into economic savings.

  17. Refuse Derived Fuel (RDF) production and gasification in a pilot plant integrated with an Otto cycle ICE through Aspen plus™ modelling: Thermodynamic and economic viability.

    PubMed

    Násner, Albany Milena Lozano; Lora, Electo Eduardo Silva; Palacio, José Carlos Escobar; Rocha, Mateus Henrique; Restrepo, Julian Camilo; Venturini, Osvaldo José; Ratner, Albert

    2017-08-07

    This work deals with the development of a Refuse Derived Fuel (RDF) gasification pilot plant using air as a gasification agent. A downdraft fixed bed reactor is integrated with an Otto cycle Internal Combustion Engine (ICE). Modelling was carried out using the Aspen Plus™ software to predict the ideal operational conditions for maximum efficiency. Thermodynamics package used in the simulation comprised the Non-Random Two-Liquid (NRTL) model and the Hayden-O'Connell (HOC) equation of state. As expected, the results indicated that the Equivalence Ratio (ER) has a direct influence over the gasification temperature and the composition of the Raw Produced Gas (RPG), and effects of ER over the Lower Heating Value (LHV) and Cold Gasification Efficiency (CGE) of the RPG are also discussed. A maximum CGE efficiency of 57-60% was reached for ER values between 0.25 and 0.3, also an average reactor temperature values in the range of 680-700°C, with a peak LHV of 5.8MJ/Nm(3). RPG was burned in an ICE, reaching an electrical power of 50kWel. The economic assessment of the pilot plant implementation was also performed, showing the project is feasible, with power above 120kWel with an initial investment of approximately US$ 300,000. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Modeling Regional Economic Impacts of Natural Disasters

    NASA Astrophysics Data System (ADS)

    Boissonnade, A.; Hallegate, S.; Muir-Wood, R.; Schlumberger, M.; Onur, T.

    2007-05-01

    Common features of natural disasters are intense regional impacts and the need for assessing their economic impacts on the construction sectors. The years 2004 and 2005 were record-setting time for natural disasters with major disasters or catastrophic (Cat) events all around the world with dramatic consequences in human lives and economic losses around the world, affecting developed and developing countries. Although there is a large body of literature on assessing the impact of cat events, there is little available research on the quantification and modeling of the regional economic impact of such events on the cost and length of reconstruction. Current available econometric models have serious limitations because they need detailed information for modeling the complex interactions between the different stakeholders of the economy at a regional level that is generally not available. Also, very little research was performed for quantifying the demand surge, defined as the sudden increase in the cost of repairs due to amplified payments, following a hurricane or a series of hurricane events or other natural disasters. Demand surge is an important component of the overall economic impact of cat events and there is a need to better quantify it. This paper presents results of a research program that started after the 2004 and 2005 U.S. hurricane seasons. A large data set of economic and observed losses resulting from the hurricanes that affected Florida and the Gulf states in the US was collected at county level. This provided us with the basis for assessing the change in repair costs before and after these historical events, to quantify the demand surge (after removing the underlying baseline trends) at several dozens of locations across the areas affected, and to provide information on how the changes in demand surge vary spatially and temporally in affected areas for which the amount of structure losses were reported. A parallel research effort was undertaken for

  19. Gross regional domestic product estimation: Application of two-way unbalanced panel data models to economic growth in East Nusa Tenggara province

    NASA Astrophysics Data System (ADS)

    Wibowo, Wahyu; Sinu, Elisabeth B.; Setiawan

    2017-03-01

    The condition of East Nusa Tenggara Province which recently developed new districts can affect the number of information or data collected become unbalanced. One of the consequences of ignoring the data incompleteness is the estimator become not valid. Therefore, the analysis of unbalanced panel data is very crucial.The aim of this paper is to find the estimation of Gross Regional Domestic Product in East Nusa Tenggara Province using unbalanced panel data regression model for two-way error component which assume random effect model (REM). In this research, we employ Feasible Generalized Least Squares (FGLS) as regression coefficients estimation method. Since variance of the model is unknown, ANOVA method is considered to obtain the variance components in order to construct the variance-covariance matrix. The data used in this research is secondary data taken from Central Bureau of Statistics of East Nusa Tenggara Province in 21 districts period 2004-2013. The predictors are the number of labor over 15 years old (X1), electrification ratios (X2), and local revenues (X3) while Gross Regional Domestic Product based on constant price 2000 is the response (Y). The FGLS estimation result shows that the value of R2 is 80,539% and all the predictors chosen are significantly affect (α = 5%) the Gross Regional Domestic Product in all district of East Nusa Tenggara Province. Those variables are the number of labor over 15 years old (X1), electrification ratios (X2), and local revenues (X3) with 0,22986, 0,090476, and 0,14749 of elasticities, respectively.

  20. [Economic dimension and environmental impact of beef production in France].

    PubMed

    Peyraud, Jean-Louis

    2011-11-01

    Following recent publication of data on its environmental impact, beef production is being strongly challenged. However, these data concern global ruminant production, which is highly diverse and does not necessarily correspond to the European and French situations. While it is undeniable that ruminant production contributes to global warming, there are several ways of mitigating greenhouse gas emissions, and permanent pastures serve as carbon sinks. Beef production is also a vital economic sector for many regions, where it would not be possible to produce cereals or to develop intensive animal production systems. Beef production also contributes to many collective services, justifying its continued financial support.

  1. Models for the Economics of Resilience.

    PubMed

    Gilbert, Stanley; Ayyub, Bilal M

    2016-12-01

    Estimating the economic burden of disasters requires appropriate models that account for key characteristics and decision making needs. Natural disasters in 2011 resulted in $366 billion in direct damages and 29,782 fatalities worldwide. Average annual losses in the US amount to about $55 billion. Enhancing community and system resilience could lead to significant savings through risk reduction and expeditious recovery. The management of such reduction and recovery is facilitated by an appropriate definition of resilience and associated metrics with models for examining the economics of resilience. This paper provides such microeconomic models, compares them, examines their sensitivities to key parameters, and illustrates their uses. Such models enable improving the resiliency of systems to meet target levels.

  2. Cognitive Capitalism: Economic Freedom Moderates the Effects of Intellectual and Average Classes on Economic Productivity.

    PubMed

    Coyle, Thomas R; Rindermann, Heiner; Hancock, Dale

    2016-10-01

    Cognitive ability stimulates economic productivity. However, the effects of cognitive ability may be stronger in free and open economies, where competition rewards merit and achievement. To test this hypothesis, ability levels of intellectual classes (top 5%) and average classes (country averages) were estimated using international student assessments (Programme for International Student Assessment; Trends in International Mathematics and Science Study; and Progress in International Reading Literacy Study) (N = 99 countries). The ability levels were correlated with indicators of economic freedom (Fraser Institute), scientific achievement (patent rates), innovation (Global Innovation Index), competitiveness (Global Competitiveness Index), and wealth (gross domestic product). Ability levels of intellectual and average classes strongly predicted all economic criteria. In addition, economic freedom moderated the effects of cognitive ability (for both classes), with stronger effects at higher levels of freedom. Effects were particularly robust for scientific achievements when the full range of freedom was analyzed. The results support cognitive capitalism theory: cognitive ability stimulates economic productivity, and its effects are enhanced by economic freedom. © The Author(s) 2016.

  3. Modelling utility-scale wind power plants. Part 1: Economics

    NASA Astrophysics Data System (ADS)

    Milligan, Michael R.

    1999-10-01

    As the worldwide use of wind turbine generators continues to increase in utility-scale applications, it will become increasingly important to assess the economic and reliability impact of these intermittent resources. Although the utility industry in the United States appears to be moving towards a restructured environment, basic economic and reliability issues will continue to be relevant to companies involved with electricity generation. This article is the first of two which address modelling approaches and results obtained in several case studies and research projects at the National Renewable Energy Laboratory (NREL). This first article addresses the basic economic issues associated with electricity production from several generators that include large-scale wind power plants. An important part of this discussion is the role of unit commitment and economic dispatch in production cost models. This paper includes overviews and comparisons of the prevalent production cost modelling methods, including several case studies applied to a variety of electric utilities. The second article discusses various methods of assessing capacity credit and results from several reliability-based studies performed at NREL.

  4. Physical-Socio-Economic Modeling of Climate Change

    NASA Astrophysics Data System (ADS)

    Chamberlain, R. G.; Vatan, F.

    2008-12-01

    Because of the global nature of climate change, any assessment of the effects of plans, policies, and response to climate change demands a model that encompasses the entire Earth System, including socio- economic factors. Physics-based climate models of the factors that drive global temperatures, rainfall patterns, and sea level are necessary but not sufficient to guide decision making. Actions taken by farmers, industrialists, environmentalists, politicians, and other policy makers may result in large changes to economic factors, international relations, food production, disease vectors, and beyond. These consequences will not be felt uniformly around the globe or even across a given region. Policy models must comprehend all of these considerations. Combining physics-based models of the Earth's climate and biosphere with societal models of population dynamics, economics, and politics is a grand challenge with high stakes. We propose to leverage our recent advances in modeling and simulation of military stability and reconstruction operations to models that address all these areas of concern. Following over twenty years' experience of successful combat simulation, JPL has started developing Minerva, which will add demographic, economic, political, and media/information models to capabilities that already exist. With these new models, for which we have design concepts, it will be possible to address a very wide range of potential national and international problems that were previously inaccessible. Our climate change model builds on Minerva and expands the geographical horizon from playboxes containing regions and neighborhoods to the entire globe. This system consists of a collection of interacting simulation models that specialize in different aspects of the global situation. They will each contribute to and draw from a pool of shared data. The basic models are: the physical model; the demographic model; the political model; the economic model; and the media

  5. Economic feasibility of agricultural alcohol production within a biomass system

    SciTech Connect

    Hertzmark, D.; Flaim, S.; Ray, D.; Parvin, G.

    1980-12-01

    The technical and economic feasibility of agricultural alcohol production in the United States is discussed. The beverage fermentation processes are compared and contrasted with the wet milling of corn, and alternative agricultural products for alcohol production are discussed. Alcohol costs for different fermentation methods and for various agricultural crops (corn, sugar cane, sugar beets, etc.) are presented, along with a brief discussion of US government policy implications. (JMT)

  6. Schumpeterian economic dynamics as a quantifiable model of evolution

    NASA Astrophysics Data System (ADS)

    Thurner, Stefan; Klimek, Peter; Hanel, Rudolf

    2010-07-01

    We propose a simple quantitative model of Schumpeterian economic dynamics. New goods and services are endogenously produced through combinations of existing goods. As soon as new goods enter the market, they may compete against already existing goods. In other words, new products can have destructive effects on existing goods. As a result of this competition mechanism, existing goods may be driven out from the market—often causing cascades of secondary defects (Schumpeterian gales of destruction). The model leads to generic dynamics characterized by phases of relative economic stability followed by phases of massive restructuring of markets—which could be interpreted as Schumpeterian business 'cycles'. Model time series of product diversity and productivity reproduce several stylized facts of economics time series on long timescales, such as GDP or business failures, including non-Gaussian fat tailed distributions and volatility clustering. The model is phrased in an open, non-equilibrium setup which can be understood as a self-organized critical system. Its diversity dynamics can be understood by the time-varying topology of the active production networks.

  7. Perspectives on the economic analysis of ethanol production from biomass

    SciTech Connect

    Prebluda, H.J.; Williams, R.

    1981-01-01

    The potential and economics of ethanol production from biomass is examined. Among the topics covered are: the Brazilian gasohol program; the effect of large scale conversion of grain to alcohol on U.S. food and animal feed prices; the Ex-Ferm process for fermenting sugar cane; the effect on cane sugar markets of the large-scale development in the U.S. of high fructose corn syrup; and better utilization of by-products. Significant breakthroughs which have recently taken place and which will improve the economic picture for making alcohol from solid waste are reviewed. (Refs. 26).

  8. An object-oriented approach to energy-economic modeling

    SciTech Connect

    Wise, M.A.; Fox, J.A.; Sands, R.D.

    1993-12-01

    In this paper, the authors discuss the experiences in creating an object-oriented economic model of the U.S. energy and agriculture markets. After a discussion of some central concepts, they provide an overview of the model, focusing on the methodology of designing an object-oriented class hierarchy specification based on standard microeconomic production functions. The evolution of the model from the class definition stage to programming it in C++, a standard object-oriented programming language, will be detailed. The authors then discuss the main differences between writing the object-oriented program versus a procedure-oriented program of the same model. Finally, they conclude with a discussion of the advantages and limitations of the object-oriented approach based on the experience in building energy-economic models with procedure-oriented approaches and languages.

  9. Sparse High Dimensional Models in Economics

    PubMed Central

    Fan, Jianqing; Lv, Jinchi; Qi, Lei

    2010-01-01

    This paper reviews the literature on sparse high dimensional models and discusses some applications in economics and finance. Recent developments of theory, methods, and implementations in penalized least squares and penalized likelihood methods are highlighted. These variable selection methods are proved to be effective in high dimensional sparse modeling. The limits of dimensionality that regularization methods can handle, the role of penalty functions, and their statistical properties are detailed. Some recent advances in ultra-high dimensional sparse modeling are also briefly discussed. PMID:22022635

  10. Techno Economic Analysis of Hydrogen Production by gasification of biomass

    SciTech Connect

    Francis Lau

    2002-12-01

    Biomass represents a large potential feedstock resource for environmentally clean processes that produce power or chemicals. It lends itself to both biological and thermal conversion processes and both options are currently being explored. Hydrogen can be produced in a variety of ways. The majority of the hydrogen produced in this country is produced through natural gas reforming and is used as chemical feedstock in refinery operations. In this report we will examine the production of hydrogen by gasification of biomass. Biomass is defined as organic matter that is available on a renewable basis through natural processes or as a by-product of processes that use renewable resources. The majority of biomass is used in combustion processes, in mills that use the renewable resources, to produce electricity for end-use product generation. This report will explore the use of hydrogen as a fuel derived from gasification of three candidate biomass feedstocks: bagasse, switchgrass, and a nutshell mix that consists of 40% almond nutshell, 40% almond prunings, and 20% walnut shell. In this report, an assessment of the technical and economic potential of producing hydrogen from biomass gasification is analyzed. The resource base was assessed to determine a process scale from feedstock costs and availability. Solids handling systems were researched. A GTI proprietary gasifier model was used in combination with a Hysys(reg. sign) design and simulation program to determine the amount of hydrogen that can be produced from each candidate biomass feed. Cost estimations were developed and government programs and incentives were analyzed. Finally, the barriers to the production and commercialization of hydrogen from biomass were determined. The end-use of the hydrogen produced from this system is small PEM fuel cells for automobiles. Pyrolysis of biomass was also considered. Pyrolysis is a reaction in which biomass or coal is partially vaporized by heating. Gasification is a more

  11. Process simulation and economical evaluation of enzymatic biodiesel production plant.

    PubMed

    Sotoft, Lene Fjerbaek; Rong, Ben-Guang; Christensen, Knud V; Norddahl, Birgir

    2010-07-01

    Process simulation and economical evaluation of an enzymatic biodiesel production plant has been carried out. Enzymatic biodiesel production from high quality rapeseed oil and methanol has been investigated for solvent free and cosolvent production processes. Several scenarios have been investigated with different production scales (8 and 200 mio. kg biodiesel/year) and enzyme price. The cosolvent production process is found to be most expensive and is not a viable choice, while the solvent free process is viable for the larger scale production of 200 mio. kg biodiesel/year with the current enzyme price. With the suggested enzyme price of the future, both the small and large scale solvent free production proved viable. The product price was estimated to be 0.73-1.49 euro/kg biodiesel with the current enzyme price and 0.05-0.75 euro/kg with the enzyme price of the future for solvent free process. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  12. Thorium: Crustal abundance, joint production, and economic availability

    DOE PAGES

    Jordan, Brett W.; Eggert, Roderick G.; Dixon, Brent W.; ...

    2015-03-02

    Recently, interest in thorium's potential use in a nuclear fuel cycle has been renewed. Thorium is more abundant, at least on average, than uranium in the earth's crust and, therefore, could theoretically extend the use of nuclear energy technology beyond the economic limits of uranium resources. This paper provides an economic assessment of thorium availability by creating cumulative-availability and potential mining-industry cost curves, based on known thorium resources. These tools provide two perspectives on the economic availability of thorium. In the long term, physical quantities of thorium likely will not be a constraint on the development of a thorium fuelmore » cycle. In the medium term, however, thorium supply may be limited by constraints associated with its production as a by-product of rare earth elements and heavy mineral sands. As a result, environmental concerns, social issues, regulation, and technology also present issues for the medium and long term supply of thorium.« less

  13. Thorium: Crustal abundance, joint production, and economic availability

    SciTech Connect

    Jordan, Brett W.; Eggert, Roderick G.; Dixon, Brent W.; Carlsen, Brett W.

    2015-03-02

    Recently, interest in thorium's potential use in a nuclear fuel cycle has been renewed. Thorium is more abundant, at least on average, than uranium in the earth's crust and, therefore, could theoretically extend the use of nuclear energy technology beyond the economic limits of uranium resources. This paper provides an economic assessment of thorium availability by creating cumulative-availability and potential mining-industry cost curves, based on known thorium resources. These tools provide two perspectives on the economic availability of thorium. In the long term, physical quantities of thorium likely will not be a constraint on the development of a thorium fuel cycle. In the medium term, however, thorium supply may be limited by constraints associated with its production as a by-product of rare earth elements and heavy mineral sands. As a result, environmental concerns, social issues, regulation, and technology also present issues for the medium and long term supply of thorium.

  14. Economic losses to Iberian swine production from forest fires

    Treesearch

    Juan Ramon Molina Martinez; Miguel Herrera Machuca; Ricardo Zamora Diaz; Fancisco Rodriguez y Silva; Armando Gonzalez-Caban

    2011-01-01

    Most forestry property in Andalusia is privately held. One of the most important possibilities for economic development of rural areas is the use of pasture lands (dehesa in Spanish). During the spring–summer season, swine grazing takes advantage of grasses between the trees, and during winter (harsher times), they use Quercus tree fruit. Swine production has a direct...

  15. A Technical and Economic Review of Solar Hydrogen Production Technologies

    ERIC Educational Resources Information Center

    Wilhelm, Erik; Fowler, Michael

    2006-01-01

    Hydrogen energy systems are being developed to replace fossil fuels-based systems for transportation and stationary application. One of the challenges facing the widespread adoption of hydrogen as an energy vector is the lack of an efficient, economical, and sustainable method of hydrogen production. In the short term, hydrogen produced from…

  16. Culturally and economically important nontimber forest products of northern Maine

    Treesearch

    Michelle J. Baumflek; Marla R. Emery; Clare. Ginger

    2010-01-01

    Nontimber forest products (NTFPs) gathered for food, medicine, craft, spiritual, aesthetic, and utilitarian purposes make substantial contributions to the economic viability and cultural vitality of communities. In the St. John River watershed of northern Maine, people identifying with cultural groups including Acadian, Maliseet, Mi'kmaq, Scotch-Irish, and Swedish...

  17. Economic Indicators of the Farm Sector. Costs of Production, 1986.

    ERIC Educational Resources Information Center

    Economic Research Service (USDA), Washington, DC.

    This report contains 121 tables that estimate the costs of production of various commodities on United States farms in 1986. The report first assesses costs and returns on a per-unit basis, such as one acre or one animal, under three sections of a budget: cash receipts, cash expenses, and economic costs. The budgets are based on national…

  18. Economic Indicators of the Farm Sector. Costs of Production, 1985.

    ERIC Educational Resources Information Center

    Economic Research Service (USDA), Washington, DC.

    This report presents the Economic Research Service's estimates of the costs of producing wheat, feed grains, cotton, and dairy commodities. It includes costs for other farm products that compete with the required commodities, namely rice, peanuts, soybeans, flax, sunflowers, fed cattle, hogs, sheep, and sugar. The report begins by assessing costs…

  19. Increased wood-fiber production: technology, economics, and ecology

    Treesearch

    William R. Bentley

    1973-01-01

    Forest tree improvement is a form of technological change, and it should be viewed as such. The economic objective of technological change is to increase productivity per dollar invested. This is accomplished through selection and breeding for increased growth rates or reduced losses to insects and disease. Programs which yield improved planting stock make forest...

  20. A Technical and Economic Review of Solar Hydrogen Production Technologies

    ERIC Educational Resources Information Center

    Wilhelm, Erik; Fowler, Michael

    2006-01-01

    Hydrogen energy systems are being developed to replace fossil fuels-based systems for transportation and stationary application. One of the challenges facing the widespread adoption of hydrogen as an energy vector is the lack of an efficient, economical, and sustainable method of hydrogen production. In the short term, hydrogen produced from…

  1. National environmental/economic infrastructure system model

    SciTech Connect

    Drake, R.H.; Hardie, R.W.; Loose, V.W.; Booth, S.R.

    1997-08-01

    This is the final report for a one-year Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The ultimate goal was to develop a new methodology for macroeconomic modeling applied to national environmental and economic problems. A modeling demonstration and briefings were produced, and significant internal technical support and program interest has been generated. External contacts with DOE`s Office of Environmental Management (DOE-EM), US State Department, and the US intelligence community were established. As a result of DOE-EM interest and requests for further development, this research has been redirected to national environmental simulations as a new LDRD project.

  2. The economic viability of smallholder timber production under expanding açaí palm production in the Amazon Estuary

    USGS Publications Warehouse

    Fortini, Lucas; Douglas R. Carter,

    2015-01-01

    Relatively little attention has been paid to the economic potentials and limitations of tropical timber production and management at smallholder scales, with the most relevant research focusing on community forestry efforts. As a rare tropical example of long-lasting small-scale timber production, in this study we explore the economics of smallholder vertically integrated timber use to better understand the activity in the context of its primary land use alternative in the Amazon Estuary, açaí palm fruit production. We use data from landowner and firm surveys, participatory monitoring of firms, and detailed forest and sawmill operation monitoring to devise financial returns models of smallholder timber micro firms and açaí palm fruit production. We then compare the economics of the two activities to better understand how differences may shape decisions at the small holder scale that impact current land use shifts in the region.

  3. Modelling the interaction between flooding events and economic growth

    NASA Astrophysics Data System (ADS)

    Grames, Johanna; Grass, Dieter; Prskawetz, Alexia; Blöschl, Günther

    2015-04-01

    Socio-hydrology describes the interaction between the socio-economy, water and population dynamics. Recent models analyze the interplay of community risk-coping culture, flooding damage and economic growth (Di Baldassarre, 2013, Viglione, 2014). These models descriptively explain the feedbacks between socio-economic development and natural disasters like floods. Contrary to these descriptive models, our approach develops an optimization model, where the intertemporal decision of an economic agent interacts with the hydrological system. This is the first economic growth model describing the interaction between the consumption and investment decisions of an economic agent and the occurrence of flooding events: Investments in defense capital can avoid floods even when the water level is high, but on the other hand such investment competes with investment in productive capital and hence may reduce the level of consumption. When floods occur, the flood damage therefore depends on the existing defense capital. The aim is to find an optimal tradeoff between investments in productive versus defense capital such as to optimize the stream of consumption in the long-term. We assume a non-autonomous exogenous periodic rainfall function (Yevjevich et.al. 1990, Zakaria 2001) which implies that the long-term equilibrium will be periodic . With our model we aim to derive mechanisms that allow consumption smoothing in the long term, and at the same time allow for optimal investment in flood defense to maximize economic output. We choose an aggregate welfare function that depends on the consumption level of the society as the objective function. I.e. we assume a social planer with perfect foresight that maximizes the aggregate welfare function. Within our model framework we can also study whether the path and level of defense capital (that protects people from floods) is related to the time preference rate of the social planner. Our model also allows to investigate how the frequency

  4. Thermodynamic laws, economic methods and the productive power of energy

    NASA Astrophysics Data System (ADS)

    Kümmel, Reiner; Ayres, Robert U.; Lindenberger, Dietmar

    2010-07-01

    Energy plays only a minor role in orthodox theories of economic growth, because standard economic equilibrium conditions say that the output elasticity of a production factor, which measures the factor's productive power, is equal to the factor's share in total factor cost. Having commanded only a tiny cost share of about 5 percent so far, energy is often neglected altogether. On the other hand, energy conversion in the machines of the capital stock has been the basis of industrial growth. How can the physically obvious economic importance of energy be reconciled with the conditions for economic equilibrium, which result from the maximization of profit or overall welfare? We show that these equilibrium conditions no longer yield the equality of cost shares and output elasticities, if the optimization calculus takes technological constraints on the combinations of capital, labor, and energy into account. New econometric analyses of economic growth in Germany, Japan, and the USA yield output elasticities that are for energy much larger and for labor much smaller than their cost shares. Social consequences are discussed.

  5. Defense Economic Impact Modeling System (DEIMS). A New Concept in Economic Forecasting for Defense Expenditures.

    ERIC Educational Resources Information Center

    Blond, David L.

    The Defense Economic Impact Modeling System (DEIMS) analyzes the economic effect of defense expenditures on the United States economy by using a consistent, reliable framework of economic models and government policy assumptions. Planning information on defense requirements is also provided to private sector firms. The DEIMS allows the Department…

  6. Economics of production efficiency: Nutritional grouping of the lactating cow.

    PubMed

    Cabrera, V E; Kalantari, A S

    2016-01-01

    Nutritional grouping of lactating cows under total mixed ration (TMR) feeding systems has been discussed in the literature since 1970. Most studies have concluded that using multiple, more-homogeneous TMR feeding groups is economically beneficial because of either nutrient cost savings, improved productivity, or both. Nonetheless, no consensus has been formed around this technique nor has it been widely adopted. By using optimal criteria for grouping and more precise nutrient specifications of diets, the latest studies have reported a consistently greater income over feed cost ($/cow per year) with multiple TMR groups compared with 1 TMR (3 TMR=$46 and 2 TMR=$21 to $39). Critical factors that determine the economic value of nutritional grouping are: (1) criteria for grouping, (2) nutrient specifications of diets, (3) effects on milk production, (4) health and environmental benefits, (5) number, size, and frequency of grouping, and (6) additional costs and benefits. It has been documented that grouping cows according to their simultaneous nutritional requirements (a.k.a., cluster grouping) is optimal. Cluster grouping is superior to other methods, such as grouping according to days in milk, milk production, or production and body weight combined. However, the dairy industry still uses less-than-optimal grouping criteria. Using cluster grouping will enhance the positive economic effects of multiple TMR. In addition, nutrient specifications of diets for groups do not seem optimal either. Milk lead factors, which are only based on group average milk production, are used. Diets could, however, be formulated more precisely based on overall group nutrient requirements. Providing more precise diets should also be in favor of grouping economics. Furthermore, an area that requires more attention is the potential negative effect of grouping on the milk production of moved cows because of either or both social interactions or diet concentration changes. Although the literature

  7. Models for Products

    ERIC Educational Resources Information Center

    Speiser, Bob; Walter, Chuck

    2011-01-01

    This paper explores how models can support productive thinking. For us a model is a "thing", a tool to help make sense of something. We restrict attention to specific models for whole-number multiplication, hence the wording of the title. They support evolving thinking in large measure through the ways their users redesign them. They assume new…

  8. Models for Products

    ERIC Educational Resources Information Center

    Speiser, Bob; Walter, Chuck

    2011-01-01

    This paper explores how models can support productive thinking. For us a model is a "thing", a tool to help make sense of something. We restrict attention to specific models for whole-number multiplication, hence the wording of the title. They support evolving thinking in large measure through the ways their users redesign them. They assume new…

  9. Integrated approach to economical, reliable, safe nuclear power production

    SciTech Connect

    Not Available

    1982-06-01

    An Integrated Approach to Economical, Reliable, Safe Nuclear Power Production is the latest evolution of a concept which originated with the Defense-in-Depth philosophy of the nuclear industry. As Defense-in-Depth provided a framework for viewing physical barriers and equipment redundancy, the Integrated Approach gives a framework for viewing nuclear power production in terms of functions and institutions. In the Integrated Approach, four plant Goals are defined (Normal Operation, Core and Plant Protection, Containment Integrity and Emergency Preparedness) with the attendant Functional and Institutional Classifications that support them. The Integrated Approach provides a systematic perspective that combines the economic objective of reliable power production with the safety objective of consistent, controlled plant operation.

  10. Short communication: economics of sex-biased milk production.

    PubMed

    Ettema, J F; Østergaard, S

    2015-02-01

    In a recent data study using 2.4 million lactations of 1.5 million cows, it was reported that gestation of a female calf in the first parity increases cumulative milk production by approximately 445kg over the first 2 lactations. The reported effect in this study is large and remarkable because it has not been found before. To our knowledge, the economic implications of this or any other sex bias have not been studied. The objective of the current study was to quantify the reported influence of fetal sex across lactations by using a simulation model of a dairy herd including youngstock. Two scenarios were evaluated and compared with a scenario in which cows and heifers were exclusively bred with conventional (nonsexed) semen. In the first scenario, sexed semen was used moderately-on 30% of all heifers and 30% of the first parity cows. A second scenario was studied in which sexed semen was used intensively-on all heifers and 50% of the first-parity cows. The simulated proportion of cows giving birth to 2 consecutive heifers increased from 23% when using exclusively conventional semen up to 31 and 48% when using sexed semen moderately and intensively, respectively. The proportion of cows having 2 consecutive bulls decreased from 27% (conventional semen only) to 20 and 8% when using sexed semen moderately and intensively, respectively. When incorporating the sex bias in the simulation model, the simulated milk yield in the scenario in which sexed semen was used moderately increased by 48kg of energy-corrected milk (ECM) per cow/yr, compared with only 36kg of ECM when not incorporating the sex bias in the model. For the scenario in which sexed semen was used intensively, milk yield increased by 66 and 99kg of ECM when excluding and including the sex bias, respectively. The economic implications of the assumed sex bias were €4.0 and €9.9 per cow/yr, in the scenarios in which sexed semen was used moderately and intensively, respectively.

  11. [Ecological economic analysis of a rice-crab model].

    PubMed

    Chen, Feixing; Zhang, Zengjie

    2002-03-01

    Based on field investigation and experimental data analysis, ecological economic principles were applied to study the structure and function, the characteristics of material and energy flows, and the economic and ecological benefits of a rice-crab model. The results show that rice-crab model had a higher integral benefit than rice model, and its net income, cost-benefit ratio, and labor productivity were increased by 382%, 67.7% and 295%, respectively. In view of the ecological benefits produced, the total nitrogen, alkaline-hydrolyzal nitrogen, total phosphorus, rapidly available phosphorus, rapidly available potassium, and organic matter in the soil after 1-year carb breeding were increased by 10.6%, 3.3%, 5.8%, 11.7%, 3.5% and 10.5%, respectively. Moreover, 6.375 kg N.hm-2 of non-point source pollution load could be cut down annually.

  12. Switchgrass biomass to ethanol production economics: Field to fuel approach

    NASA Astrophysics Data System (ADS)

    Haque, Mohua

    Scope and Method of Study. Switchgrass has been proposed as a dedicated energy crop. The first essay determines switchgrass yield response to nitrogen fertilizer for a single annual harvest in July and for a single annual harvest in October based on a field experiments conducted at Stillwater, OK. Data were fitted to several functional forms to characterize both the July harvest and the October harvest response functions. Extending the harvest window to take advantage of reduction in harvest machinery investment costs has important biological consequences. The second essay determines the cost to deliver a ton of switchgrass biomass to a 2,000 tons per day plant located in Oklahoma. The model accounts for differences in yield and nitrogen fertilizer requirements across harvest months. The data were incorporated into a multi-region, multi-period, monthly time-step, mixed integer mathematical programming model that was constructed to determine the optimal strategy. Desirable feedstock properties, biomass to biofuel conversion rate, and investment required in plant differs depending on which conversion technology is used. The third essay determines the breakeven ethanol price for a cellulosic biorefinery. A comprehensive mathematical programming model that encompasses the chain from land acquisition to ethanol production was constructed and solved. Findings and Conclusions. The July and October harvest plateau yield of 4.36 and 5.49 tons per acre were achieved with an estimated annual nitrogen fertilizer application of 80 and 63 pounds per acre, respectively. Farm gate production costs were estimated to be 60 per ton for the July harvest and 50 per ton for the October harvest. Based on the model results, the strategy of extending harvest over many months is economically preferable to a strategy of harvesting only in peak yield harvest months. Restricting harvest to a two-month harvest season would increase the cost to deliver feedstock by 23 percent. For a capital

  13. Home Economics Education Career Path Guide and Model Curriculum Standards.

    ERIC Educational Resources Information Center

    California State Univ., Northridge.

    This curriculum guide developed in California and organized in 10 chapters, provides a home economics education career path guide and model curriculum standards for high school home economics programs. The first chapter contains information on the following: home economics education in California, home economics careers for the future, home…

  14. Home Economics Education Career Path Guide and Model Curriculum Standards.

    ERIC Educational Resources Information Center

    California State Univ., Northridge.

    This curriculum guide developed in California and organized in 10 chapters, provides a home economics education career path guide and model curriculum standards for high school home economics programs. The first chapter contains information on the following: home economics education in California, home economics careers for the future, home…

  15. Floating production systems in a ``new economic regime``

    SciTech Connect

    Eriksen, K.; D`Souza, R.B.; Wilson, A.J.S.; Johansson, O.

    1995-12-31

    Except for a short period before, during and after the Gulf War, the oil prices have been depressed for 8--10 years. This has forced industry to be profitable at these low oil price levels. Since 1975 various floating production systems have been evaluated and used as field development solutions around the world. As technical challenges have been overcome, floating production systems have become leading contenders for traditional and deepwater field developments in this new economic regime. There are many types of Floating production systems. A few examples are--the semisubmersible Floating Production System (FPS), the monohull Floating Production, Storage and Offloading system (FPSO), the Spar Buoy and the Deep Draft Floater. As the FPS and FPSO represent proven technology and are leading contenders for several field developments in both the North Sea and the Gulf of Mexico, this paper will concentrate on these concepts.

  16. Breeding objectives for pigs in Kenya. II: economic values incorporating risks in different smallholder production systems.

    PubMed

    Mbuthia, Jackson Mwenda; Rewe, Thomas Odiwuor; Kahi, Alexander Kigunzu

    2015-02-01

    This study estimated economic values for production traits (dressing percentage (DP), %; live weight for growers (LWg), kg; live weight for sows (LWs), kg) and functional traits (feed intake for growers (FEEDg), feed intake for sow (FEEDs), preweaning survival rate (PrSR), %; postweaning survival (PoSR), %; sow survival rate (SoSR), %, total number of piglets born (TNB) and farrowing interval (FI), days) under different smallholder pig production systems in Kenya. Economic values were estimated considering two production circumstances: fixed-herd and fixed-feed. Under the fixed-herd scenario, economic values were estimated assuming a situation where the herd cannot be increased due to other constraints apart from feed resources. The fixed-feed input scenario assumed that the herd size is restricted by limitation of feed resources available. In addition to the tradition profit model, a risk-rated bio-economic model was used to derive risk-rated economic values. This model accounted for imperfect knowledge concerning risk attitude of farmers and variance of input and output prices. Positive economic values obtained for traits DP, LWg, LWs, PoSR, PrSR, SoSR and TNB indicate that targeting them in improvement would positively impact profitability in pig breeding programmes. Under the fixed-feed basis, the risk-rated economic values for DP, LWg, LWs and SoSR were similar to those obtained under the fixed-herd situation. Accounting for risks in the EVs did not yield errors greater than ±50 % in all the production systems and basis of evaluation meaning there would be relatively little effect on the real genetic gain of a selection index. Therefore, both traditional and risk-rated models can be satisfactorily used to predict profitability in pig breeding programmes.

  17. Developing models that analyze the economic/environmental trade-offs implicit in water resource management

    NASA Astrophysics Data System (ADS)

    Howitt, R. E.

    2016-12-01

    Hydro-economic models have been used to analyze optimal supply management and groundwater use for the past 25 years. They are characterized by an objective function that usually maximizes economic measures such as consumer and producer surplus subject to hydrologic equations of motion or water distribution systems. The hydrologic and economic components are sometimes fully integrated. Alternatively they may use an iterative interactive process. Environmental considerations have been included in hydro-economic models as inequality constraints. Representing environmental requirements as constraints is a rigid approximation of the range of management alternatives that could be used to implement environmental objectives. The next generation of hydro-economic models, currently being developed, require that the environmental alternatives be represented by continuous or semi-continuous functions which relate water resource use allocated to the environment with the probabilities of achieving environmental objectives. These functions will be generated by process models of environmental and biological systems which are now advanced to the state that they can realistically represent environmental systems and flexibility to interact with economic models. Examples are crop growth models, climate modeling, and biological models of forest, fish, and fauna systems. These process models can represent environmental outcomes in a form that is similar to economic production functions. When combined with economic models the interacting process models can reproduce a range of trade-offs between economic and environmental objectives, and thus optimize social value of many water and environmental resources. Some examples of this next-generation of hydro-enviro- economic models are reviewed. In these models implicit production functions for environmental goods are combined with hydrologic equations of motion and economic response functions. We discuss models that show interaction between

  18. JPRS Report, Soviet Union, EKO: Economics & Organization of Industrial Production.

    DTIC Science & Technology

    1988-03-28

    Scientific Works of R. G. Karagedov: "Pribyl v sisteme ekonomicheskikh kategoriy sotsia- lizma" [Profit in the System of Economic Categories of...Laser Beam (1) Roborization: Problems of Effectiveness L. I. Volchkevich. A Robot Is a Robot ! (4) Yu. A. Gorodner and V. F. Zaluzhentsev. What Is...Reducing the Productivity of Robots ! (4) V. A. Shibeko. It Is Time To Grow Up (4) Systems and Methods of Management. Management Consulting M. A

  19. Software development for the economic model of R.Barro

    NASA Astrophysics Data System (ADS)

    Kalimoldayev, Maksat N.; Amirkhanova, Gulshat A.

    2016-12-01

    In this paper we describe the process of creating software for R.Barro economic model. The goal of the paper is the analysis of existing languages and platforms and selections of them as means for developing advanced software for modeling economic processes, and also the construction of algorithms and programs using traditional and modern methods of software development. Prototyping was selected as an approach for the development, it allows us to obtain in a short time the product, which is available for testing and further improvement in order to meet the requirements. The paper describes the version of the program that meets the recommended requirements, shows the schematic diagram of this program and describes its main functions.

  20. The nutrition intervention improved adult human capital and economic productivity.

    PubMed

    Martorell, Reynaldo; Melgar, Paul; Maluccio, John A; Stein, Aryeh D; Rivera, Juan A

    2010-02-01

    This article reviews key findings about the long-term impact of a nutrition intervention carried out by the Institute of Nutrition of Central America and Panama from 1969 to 1977. Results from follow-up studies in 1988-89 and 2002-04 show substantial impact on adult human capital and economic productivity. The 1988-89 study showed that adult body size and work capacity increased for those provided improved nutrition through age 3 y, whereas the 2002-04 follow-up showed that schooling was increased for women and reading comprehension and intelligence increased in both men and women. Participants were 26-42 y of age at the time of the 2002-04 follow-up, facilitating the assessment of economic productivity. Wages of men increased by 46% in those provided with improved nutrition through age 2 y. Findings for cardiovascular disease risk factors were heterogeneous; however, they suggest that improved nutrition in early life is unlikely to increase cardiovascular disease risk later in life and may indeed lower risk. In conclusion, the substantial improvement in adult human capital and economic productivity resulting from the nutrition intervention provides a powerful argument for promoting improvements in nutrition in pregnant women and young children.

  1. Economic and environmental assessment of syrup production. Colombian case.

    PubMed

    Dávila, Javier A; Hernández, Valentina; Castro, Eulogio; Cardona, Carlos A

    2014-06-01

    This work presents a techno-economic and environmental assessment of the glucose syrups production from sugarcane bagasse, plantain husk, cassava husk, mango peel, rice husk and corncobs. According to the economic analysis, the corncob had both, the lowest production cost (2.48USD/kg syrup) and the highest yield (0.61kgofsugars/kg of wet agroindustrial waste) due to its high content in cellulose and hemicellulose. This analysis also revealed that a heat integration strategy is necessary since the utilities consumption represent an important factor in the production cost. According to the results, the pretreatment section requires more energy in the syrup production in comparison with the requirements of other sections such as production and sugar concentration. The environmental assessment revealed that the solid wastes such as furfural and hydroxymethylfurfural affected the environmental development of the process for all the agroindustrial wastes, being the rice husk the residue with the lowest environmental impact. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. SRWC bioenergy productivity and economic feasibility on marginal lands.

    PubMed

    Ghezehei, Solomon B; Shifflett, Shawn D; Hazel, Dennis W; Nichols, Elizabeth Guthrie

    2015-09-01

    Evolving bioenergy markets necessitate consideration of marginal lands for woody biomass production worldwide particularly the southeastern U.S., a prominent wood pellet exporter to Europe. Growing short rotation woody crops (SRWCs) on marginal lands minimizes concerns about using croplands for bioenergy production and reinforces sustainability of wood supply to existing and growing global biomass markets. We estimated mean annual aboveground green biomass increments (MAIs) and assessed economic feasibility of various operationally established (0.5 ha-109 ha) SRWC stands on lands used to mitigate environmental liabilities of municipal wastewater, livestock wastewater and sludge, and subsurface contamination by petroleum and pesticides. MAIs (Mg ha(-1) yr(-1)) had no consistent relationship with stand density or age. Non-irrigated Populus, Plantanus occidentalis L. and Pinus taeda L. stands produced 2.4-12.4 Mg ha(-1) yr(-1). Older, irrigated Taxodium distchum L., Fraxinus pennsylvanica L., and coppiced P. occidentalis stands had higher MAIs (10.6-21.3 Mg ha(-1) yr(-1)) than irrigated Liquidambar styraciflua L. and non-coppiced, irrigated P. occidentalis (8-18 Mg ha(-1) yr(-1)). Natural hardwood MAIs at 20-60 years were less than hardwood and P. taeda productivities at 5-20 years. Unlike weed control, irrigation and coppicing improved managed hardwood productivity. Rotation length affected economic outcomes although the returns were poor due to high establishment and maintenance costs, low productivities and low current stumpage values, which are expected to quickly change with development of robust global markets.

  3. Impacts of supplyshed-level differences in productivity and land Costs on the economics of hybrid poplar production in Minnesota, USA

    Treesearch

    William Lazarus; William L. Headlee; Ronald S. Zalesny

    2015-01-01

    The joint effects of poplar biomass productivity and land costs on poplar production economics were compared for 12 Minnesota counties and two genetic groups, using a process-based model (3-PG) to estimate productivity. The counties represent three levels of productivity and a range of land costs (annual rental rates) from $128/ha to $534/ha. An optimal rotation age...

  4. Upstream and downstream strategies to economize biodiesel production.

    PubMed

    Hasheminejad, Meisam; Tabatabaei, Meisam; Mansourpanah, Yaghoub; Khatami far, Mahdi; Javani, Azita

    2011-01-01

    In recent years biodiesel has drawn considerable amount of attention as a clean and renewable fuel. Biodiesel is produced from renewable sources such as vegetable oils and animal fat mainly through catalytic or non-catalytic transesterification method as well as supercritical method. However, as a consequence of disadvantages of these methods, the production cost increases dramatically. This article summarizes different biodiesel production methods with a focus on their advantages and disadvantages. The downstream and upstream strategies such as using waste cooking oils, application of non-edible plant oils, plant genetic engineering, using membrane separation technology for biodiesel production, separation and purification, application of crude glycerin as an energy supplement for ruminants, glycerin ultra-purification and their consequent roles in economizing the production process are fully discussed in this article. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Impact of production strategies and animal performance on economic values of dairy sheep traits.

    PubMed

    Krupová, Z; Wolfová, M; Krupa, E; Oravcová, M; Daňo, J; Huba, J; Polák, P

    2012-03-01

    The objective of this study was to carry out a sensitivity analysis on the impact of various production strategies and performance levels on the relative economic values (REVs) of traits in dairy sheep. A bio-economic model implemented in the program package ECOWEIGHT was used to simulate the profit function for a semi-extensive production system with the Slovak multi-purpose breed Improved Valachian and to calculate the REV of 14 production and functional traits. The following production strategies were analysed: differing proportions of milk processed to cheese, customary weaning and early weaning of lambs with immediate sale or sale after artificial rearing, seasonal lambing in winter and aseasonal lambing in autumn. Results of the sensitivity analysis are presented in detail for the four economically most important traits: 150 days milk yield, conception rate of ewes, litter size and ewe productive lifetime. Impacts of the differences in the mean value of each of these four traits on REVs of all other traits were also examined. Simulated changes in the production circumstances had a higher impact on the REV for milk yield than on REVs of the other traits investigated. The proportion of milk processed to cheese, weaning management strategy for lambs and level of milk yield were the main factors influencing the REV of milk yield. The REVs for conception rate of ewes were highly sensitive to the current mean level of the trait. The REV of ewe productive lifetime was most sensitive to variation in ewe conception rate, and the REV of litter size was most affected by weaning strategy for lambs. On the basis of the results of sensitivity analyses, it is recommended that economic values of traits for the overall breeding objective for dairy sheep be calculated as the weighted average of the economic values obtained for the most common production strategies of Slovak dairy sheep farms and that economic values be adjusted after substantial changes in performance levels

  6. An economic model for evaluating high-speed aircraft designs

    NASA Technical Reports Server (NTRS)

    Vandervelden, Alexander J. M.

    1989-01-01

    A Class 1 method for determining whether further development of a new aircraft design is desirable from all viewpoints is presented. For the manufacturer the model gives an estimate of the total cost of research and development from the preliminary design to the first production aircraft. Using Wright's law of production, one can derive the average cost per aircraft produced for a given break-even number. The model will also provide the airline with a good estimate of the direct and indirect operating costs. From the viewpoint of the passenger, the model proposes a tradeoff between ticket price and cruise speed. Finally all of these viewpoints are combined in a Comparative Aircraft Seat-kilometer Economic Index.

  7. Attribution of hydrologic trends using integrated hydrologic and economic models

    NASA Astrophysics Data System (ADS)

    Maneta, M. P.; Brugger, D. R.; Silverman, N. L.

    2014-12-01

    Hydrologic change has been detected in many regions of the world in the form of trends in annual streamflows, varying depths to the regional water table, or other alterations of the hydrologic balance. Most models used to investigate these changes implement sophisticated descriptions of the physical system but use simplified descriptions of the socioeconomic system. These simplifications come in the form of prescribed water diversions and land use change scenarios, which provide little insight into coupled natural-human systems and have limited predictive capabilities. We present an integrated model that adds realism to the description of the hydrologic system in agricultural regions by incorporating a component that updates the allocation of land and water to crops in response to hydroclimatic (water available) and economic conditions (prices of commodities and agricultural inputs). This component assumes that farmers allocate resources to maximize their net revenues, thus justifying the use of optimality conditions to constrain the parameters of an empirical production function that captures the economic behavior of farmers. Because the model internalizes the feedback between climate, agricultural markets, and farming activity into the hydrologic system, it can be used to understand to what extent human economic activity can exacerbate or buffer the regional hydrologic impacts of climate change in agricultural regions. It can also help in the attribution of causes of hydrologic change. These are important issues because local policy and management cannot solve climate change, but they can address land use and agricultural water use. We demonstrate the model in a case study.

  8. The economic prospects of cellulosic biomass for biofuel production

    NASA Astrophysics Data System (ADS)

    Kumarappan, Subbu

    competitive with existing crops, and additional subsidy support would be required. Among the states in the eastern half of US, the states of Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, and Virginia are found to be economically more suitable to cultivate perennial energy crops. The third paper estimates the optimal feedstock composition of annual and perennial feedstocks from a biorefinery's perspective. The objective function of the optimization model is to minimize the cumulative costs covering harvesting, transport, storage, and GHG costs, of biomass procurement over a biorefinery's productive period of 20 years subject to various constraints on land availability, feedstock availability, processing capacity, contracting needs and storage. The results suggest that the economic tradeoff is between higher production costs for dedicated energy crops and higher collection and transport costs for agricultural residues; the delivered costs of biomass drives the results. These tradeoffs are reflected in optimal spatial planting pattern as preferred by the biorefinery: energy crops are grown in fields closer to the biorefinery and agricultural residues can be sourced from fields farther away from the biorefinery. The optimization model also provides useful insights into the price premiums paid for annual and perennial feedstocks. For the parameters used in the case study, the energy crop price premium ranges from 2 to 8 per ton for fields located within a 10 mile radius. For agricultural residues, the price premiums range from 5 to 16 per ton within a 10-20 mile radius.

  9. Technology and economic assessment of lactic acid production and uses

    SciTech Connect

    Datta, R.; Tsai, S.P.

    1996-03-01

    Lactic acid has been an intermediate-volume specialty chemical (world production {approximately}50,000 tons/yr) used in a wide range of food-processing and industrial applications. Potentially, it can become a very large-volume, commodity-chemical intermediate produced from carbohydrates for feedstocks of biodegradable polymers, oxygenated chemicals, environmentally friendly ``green`` solvents, and other intermediates. In the past, efficient and economical technologies for the recovery and purification of lactic acid from fermentation broths and its conversion to the chemical or polymer intermediates had been the key technology impediments and main process cost centers. Development and deployment of novel separations technologies, such as electrodialysis with bipolar membranes, extractive and catalytic distillations, and chemical conversion, can enable low-cost production with continuous processes in large-scale operations. The emerging technologies can use environmentally sound lactic acid processes to produce environmentally useful products, with attractive process economics. These technology advances and recent product and process commercialization strategies are reviewed and assessed.

  10. International Jobs and Economic Development Impacts (I-JEDI) Model

    SciTech Connect

    2016-09-01

    International Jobs and Economic Development Impacts (I-JEDI) is a freely available economic model that estimates gross economic impacts from wind, solar, biomass, and geothermal energy projects. Building on a similar model for the United States, I-JEDI was developed by the National Renewable Energy Laboratory under the U.S. government's Enhancing Capacity for Low Emission Development Strategies (EC-LEDS) program to support partner countries in assessing economic impacts of LEDS actions in the energy sector.

  11. Total Economic Value of Wetlands Products and Services in Uganda

    PubMed Central

    Kakuru, Willy; Turyahabwe, Nelson; Mugisha, Johnny

    2013-01-01

    Wetlands provide food and non-food products that contribute to income and food security in Uganda. This study determined the economic value of wetland resources and their contribution to food security in the three agroecological zones of Uganda. The values of wetland resources were estimated using primary and secondary data. Market price, Productivity, and Contingent valuation methods were used to estimate the value of wetland resources. The per capita value of fish was approximately US$ 0.49 person−1. Fish spawning was valued at approximately US$ 363,815 year−1, livestock pastures at US$ 4.24 million, domestic water use at US$ 34 million year−1, and the gross annual value added by wetlands to milk production at US$ 1.22 million. Flood control was valued at approximately US$ 1,702,934,880 hectare−1 year−1 and water regulation and recharge at US$ 7,056,360 hectare−1 year−1. Through provision of grass for mulching, wetlands were estimated to contribute to US$ 8.65 million annually. The annual contribution of non-use values was estimated in the range of US$ 7.1 million for water recharge and regulation and to US$ 1.7 billion for flood control. Thus, resource investment for wetlands conservation is economically justified to create incentives for continued benefits. PMID:24163614

  12. Total economic value of wetlands products and services in Uganda.

    PubMed

    Kakuru, Willy; Turyahabwe, Nelson; Mugisha, Johnny

    2013-01-01

    Wetlands provide food and non-food products that contribute to income and food security in Uganda. This study determined the economic value of wetland resources and their contribution to food security in the three agroecological zones of Uganda. The values of wetland resources were estimated using primary and secondary data. Market price, Productivity, and Contingent valuation methods were used to estimate the value of wetland resources. The per capita value of fish was approximately US$ 0.49 person⁻¹. Fish spawning was valued at approximately US$ 363,815 year⁻¹, livestock pastures at US$ 4.24 million, domestic water use at US$ 34 million year⁻¹, and the gross annual value added by wetlands to milk production at US$ 1.22 million. Flood control was valued at approximately US$ 1,702,934,880 hectare⁻¹ year⁻¹ and water regulation and recharge at US$ 7,056,360 hectare⁻¹ year⁻¹. Through provision of grass for mulching, wetlands were estimated to contribute to US$ 8.65 million annually. The annual contribution of non-use values was estimated in the range of US$ 7.1 million for water recharge and regulation and to US$ 1.7 billion for flood control. Thus, resource investment for wetlands conservation is economically justified to create incentives for continued benefits.

  13. Effects of sex control and twinning on economic optimization of culling cows in Japanese Black cow-calf production systems.

    PubMed

    Oishi, K; Hirooka, H

    2012-01-15

    The effects of sex control and twinning techniques on determination of optimal culling parity of cows in beef cow-calf production systems were deterministically analyzed using a herd model simulation. The model simulated the annualized net revenue as an economic indicator during the whole life cycle of a cow. Biological factors (survivability, growth, reproduction, and feed requirements) and economic factors (returns from sales of live calves and cows' carcasses and production costs) were included in the model. Some biological and economic parameters relating to these factors were altered from a base condition in order to adapt the production systems with sex control and twinning techniques. Based on the model, early culling was optimal for all production systems when biological efficiency was used as an indicator of production; however, later culling was optimal for single production, but slightly earlier culling was optimal for twin production, when annualized net revenue was evaluated. The introduction of sex control did not greatly affect the determination of the optimal culling parity of cows. When production included the sex control, female sexing increased biological efficiency, whereas male sexing increased annualized net revenue. In the present beef cow-calf production circumstances in Japan, introduction of sex control did not have economically appreciable effects, but twinning was economically beneficial. For production involving sex control, improvement in the conception rate per mating and/or reduction of technical cost were required for this technology to be profitable. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Assessing Expertise in Economic Problem Solving: A Model.

    ERIC Educational Resources Information Center

    Miller, Steven L.; VanFossen, Phillip J.

    1994-01-01

    Examines research literature and schematic models associated with the expert-novice model in cognitive psychology. Describes a model for rendering expertise in problem solving within economics. Reports that a preliminary study indicates that this model effectively rendered both expert and novice problem solving in economics. (CFR)

  15. An integrated hydrological, ecological, and economical (HEE) modeling system for assessing water resources and ecosystem production: calibration and validation in the upper and middle parts of the Yellow River Basin, China

    NASA Astrophysics Data System (ADS)

    Li, Xianglian; Yang, Xiusheng; Gao, Wei

    2006-08-01

    Effective management of water resources in arid and semi-arid areas demands studies that cross over the disciplinaries of natural and social sciences. An integrated Hydrological, Ecological and Economical (HEE) modeling system at regional scale has been developed to assess water resources use and ecosystem production in arid and semi-arid areas. As a physically-based distributed modeling system, the HEE modeling system requires various input parameters including those for soil, vegetation, topography, groundwater, and water and agricultural management at different spatial levels. A successful implementation of the modeling system highly depends on how well it is calibrated. This paper presented an automatic calibration procedure for the HEE modeling system and its test in the upper and middle parts of the Yellow River basin. Previous to calibration, comprehensive literature investigation and sensitivity analysis were performed to identify important parameters for calibration. The automatic calibration procedure was base on conventional Monte Carlo sampling method together with a multi-objective criterion for calibration over multi-site and multi-output. The multi-objective function consisted of optimizing statistics of mean absolute relative error (MARE), Nash-Sutcliffe model efficiency coefficient (E NS), and coefficient of determination (R2). The modeling system was calibrated against streamflow and harvest yield data from multiple sites/provinces within the basin over 2001 by using the proposed automatic procedure, and validated over 1993-1995. Over the calibration period, the mean absolute relative error of simulated daily streamflow was within 7% while the statistics R2 and E NS of daily streamflow were 0.61 and 0.49 respectively. Average simulated harvest yield over the calibration period was about 9.2% less than that of observations. Overall calibration results have indicated that the calibration procedures developed in this study can efficiently calibrate

  16. The impact of economic crisis on the Greek hospitals' productivity.

    PubMed

    Mitropoulos, Panagiotis; Mitropoulos, Ioannis; Karanikas, Haralampos; Polyzos, Nikolaos

    2017-04-10

    During the recent economic crisis, Greece implemented a comprehensive reform in the health care system. The 2010 health reform occurred under the constraints imposed by the memorandum of understanding that the Greek Government signed with its EU/International Monetary Fund creditors to control its deficit. The objective of the study is to examine the impact of the reform on the efficiency and productivity of public hospitals in Greece. We use the Malmquist productivity index to comparatively examine the potential changes before and after the reform years. We compare productivity, efficiency, and technological changes using panel data of 111 public acute hospitals operating in Greece throughout the recession period of 2009 to 2012. Bootstrapping methods are applied to allow for uncertainty owing to sampling error and for statistical inference for the Malmquist productivity index and its decompositions. The analysis indicates that the productivity has been increased following the policy changes. It appears that the expected benefits from the reform in general have been achieved, at least in the short-term. This result is examined in the light of management and operations activities, which are related with the reform process. Therefore, at a second stage, the Malmquist index is regressed on variables that may potentially be statistically associated with productivity growth.

  17. An Economic Evaluation of Binary Cycle Geothermal Electricity Production

    DTIC Science & Technology

    2003-03-01

    Fridleifsson, I. B. "The Role of Goethermal Energy in the World," Geo-Heat Center Quarterly Bulletin, Vol 17, Iss 3: 1-5 31 Aug 1996. Gawlik, K. and C...ENV/03-07 Abstract The U.S. is heavily dependent on fossil fuels to produce electricity. Geothermal energy , the heat in the earth’s crust, can...provide an alternative source of energy for electricity production as well as reduce fossil fuel consumption. The economic analysis presented in this

  18. [Economic determinants of the demand for importation of pharmacochemical and pharmaceutical products].

    PubMed

    Santos, Anderson Moreira Aristides Dos; Tejada, César Augusto Oviedo; Jacinto, Paulo de Andrade

    2017-09-28

    : This article analyzes the relationship between the demand for importation of pharmacochemical and pharmaceutical products and economic variables (exchange rate, import prices, and aggregate income) in Brazil, using monthly data from 1997-2014. The main results showed that increases in aggregate income and price reductions in imports have a positive and significant impact (elastic and inelastic, respectively) on imports. Exchange rate was only significant in the more aggregate model. Thus, aggregate income was a robust variable with strong impact on the importation of pharmacochemical and pharmaceutical products. The arguments in the literature that this industry's international trade deficit is related to a deficit in knowledge and technology and the current study's results provide evidence that as economic activity grows, there is a greater demand for this type of product. Additionally, if domestic production is insufficient, there is a need for imports, which can generate pressure on the trade deficit in the industry and contribute to Brazil's dependence on other countries.

  19. Economic evaluation of United States ethanol production from ligno-cellulosic feedstocks

    NASA Astrophysics Data System (ADS)

    Choi, Youn-Sang

    This paper evaluates the economic feasibility and economy-wide impacts of the U. S. ethanol production from lignocellulosic feedstocks (LCF) using Tennessee Valley Authority's (TVA's) dilute acid hydrolysis process. A nonlinear mathematical programming model of a single ethanol producer, whose objective is profit maximization, is developed. Because of differences in their chemical composition and production process, lignocellulosic feedstocks are divided into two groups: Biomass feedstocks, which refer to crop residues, energy crops and woody biomass, and municipal solid waste (MSW). Biomass feedstocks are more productive and less costly in producing ethanol and co-products, while MSW generates an additional income to the producer from a tipping fee and recycling. The analysis suggests that, regardless of types of feedstocks used, TVA's conversion process can enhance the economic viability of ethanol production as long as furfural is produced from the hemicellulose fraction of feedstocks as a co-product. The high price of furfural makes it a major factor in determining the economic feasibility of ethanol production. Along with evaluating economic feasibility of LCF-to-ethanol production, the optimal size of a plant producing ethanol using TVA's conversion process is estimated. The larger plant would have the advantage of economies of scale, but also have a disadvantage of increased collection and transportation costs for bulky biomass from more distant locations. We assume that the plant is located in the state of Missouri and utilizes only feedstocks produced in the state. The results indicate that the size of a plant using Biomass feedstocks is much bigger than one using MSW. The difference of plant sizes results from plant location and feedstock availability. One interesting finding is that energy crops are not feasible feedstocks for LCF-to-ethanol production due to their high price. Next, a static CGE model is developed to estimate the U.S. economy

  20. Uncertainty in techno-economic estimates of cellulosic ethanol production due to experimental measurement uncertainty.

    PubMed

    Vicari, Kristin J; Tallam, Sai Sandeep; Shatova, Tatyana; Joo, Koh Kang; Scarlata, Christopher J; Humbird, David; Wolfrum, Edward J; Beckham, Gregg T

    2012-04-17

    Cost-effective production of lignocellulosic biofuels remains a major financial and technical challenge at the industrial scale. A critical tool in biofuels process development is the techno-economic (TE) model, which calculates biofuel production costs using a process model and an economic model. The process model solves mass and energy balances for each unit, and the economic model estimates capital and operating costs from the process model based on economic assumptions. The process model inputs include experimental data on the feedstock composition and intermediate product yields for each unit. These experimental yield data are calculated from primary measurements. Uncertainty in these primary measurements is propagated to the calculated yields, to the process model, and ultimately to the economic model. Thus, outputs of the TE model have a minimum uncertainty associated with the uncertainty in the primary measurements. We calculate the uncertainty in the Minimum Ethanol Selling Price (MESP) estimate for lignocellulosic ethanol production via a biochemical conversion process: dilute sulfuric acid pretreatment of corn stover followed by enzymatic hydrolysis and co-fermentation of the resulting sugars to ethanol. We perform a sensitivity analysis on the TE model and identify the feedstock composition and conversion yields from three unit operations (xylose from pretreatment, glucose from enzymatic hydrolysis, and ethanol from fermentation) as the most important variables. The uncertainty in the pretreatment xylose yield arises from multiple measurements, whereas the glucose and ethanol yields from enzymatic hydrolysis and fermentation, respectively, are dominated by a single measurement: the fraction of insoluble solids (fIS) in the biomass slurries. We calculate a $0.15/gal uncertainty in MESP from the TE model due to uncertainties in primary measurements. This result sets a lower bound on the error bars of the TE model predictions. This analysis highlights the

  1. Uncertainty in techno-economic estimates of cellulosic ethanol production due to experimental measurement uncertainty

    PubMed Central

    2012-01-01

    Background Cost-effective production of lignocellulosic biofuels remains a major financial and technical challenge at the industrial scale. A critical tool in biofuels process development is the techno-economic (TE) model, which calculates biofuel production costs using a process model and an economic model. The process model solves mass and energy balances for each unit, and the economic model estimates capital and operating costs from the process model based on economic assumptions. The process model inputs include experimental data on the feedstock composition and intermediate product yields for each unit. These experimental yield data are calculated from primary measurements. Uncertainty in these primary measurements is propagated to the calculated yields, to the process model, and ultimately to the economic model. Thus, outputs of the TE model have a minimum uncertainty associated with the uncertainty in the primary measurements. Results We calculate the uncertainty in the Minimum Ethanol Selling Price (MESP) estimate for lignocellulosic ethanol production via a biochemical conversion process: dilute sulfuric acid pretreatment of corn stover followed by enzymatic hydrolysis and co-fermentation of the resulting sugars to ethanol. We perform a sensitivity analysis on the TE model and identify the feedstock composition and conversion yields from three unit operations (xylose from pretreatment, glucose from enzymatic hydrolysis, and ethanol from fermentation) as the most important variables. The uncertainty in the pretreatment xylose yield arises from multiple measurements, whereas the glucose and ethanol yields from enzymatic hydrolysis and fermentation, respectively, are dominated by a single measurement: the fraction of insoluble solids (fIS) in the biomass slurries. Conclusions We calculate a $0.15/gal uncertainty in MESP from the TE model due to uncertainties in primary measurements. This result sets a lower bound on the error bars of the TE model predictions

  2. Economical Recovery of By-products in the Mining Industry

    SciTech Connect

    Berry, J.B.

    2001-12-05

    The U.S. Department of Energy (DOE) Office of Industrial Technologies, Mining Industry of the Future Program, works with the mining industry to further the industry's advances toward environmental and economic goals. Two of these goals are (1) responsible emission and by-product management and (2) low-cost and efficient production (DOE 1998). DOE formed an alliance with the National Mining Association (NMA) to strengthen the basis for research projects conducted to benefit the mining industry. NMA and industry representatives actively participate in this alliance by evaluating project proposals and by recommending research project selection to DOE. Similarly, the National Research Council (NRC) has recently and independently recommended research and technology development opportunities in the mining industry (NRC 2001). The Oak Ridge National Laboratory (ORNL) and Colorado School of Mines engineers conducted one such project for DOE regarding by -product recovery from mining process residue. The results of this project include this report on mining industry process residue and waste with opportunity for by-product recovery. The U.S. mineral processing industry produces over 30,000,000 metric tons per year of process residue and waste that may contain hazardous species as well as valuable by-products. This study evaluates the copper, lead, and zinc commodity sectors which generate between 23,300,000 and 24,000,000 metric tons per year. The distribution of residual elements in process residues and wastes varies over wide ranges* because of variations in the original ore content as it is extracted from the earth's crust. In the earth's crust, the elements of interest to mining fall into two general geochemical classifications, lithophiles and chalcophiles** (Cox 1997). Groups of elements are almost always present together in a given geochemical classification, but the relative amounts of each element are unique to a particular ore body. This paper generally describes

  3. Advanced Small Modular Reactor Economics Model Development

    SciTech Connect

    Harrison, Thomas J.

    2014-10-01

    The US Department of Energy Office of Nuclear Energy’s Advanced Small Modular Reactor (SMR) research and development activities focus on four key areas: Developing assessment methods for evaluating advanced SMR technologies and characteristics; and Developing and testing of materials, fuels and fabrication techniques; and Resolving key regulatory issues identified by US Nuclear Regulatory Commission and industry; and Developing advanced instrumentation and controls and human-machine interfaces. This report focuses on development of assessment methods to evaluate advanced SMR technologies and characteristics. Specifically, this report describes the expansion and application of the economic modeling effort at Oak Ridge National Laboratory. Analysis of the current modeling methods shows that one of the primary concerns for the modeling effort is the handling of uncertainty in cost estimates. Monte Carlo–based methods are commonly used to handle uncertainty, especially when implemented by a stand-alone script within a program such as Python or MATLAB. However, a script-based model requires each potential user to have access to a compiler and an executable capable of handling the script. Making the model accessible to multiple independent analysts is best accomplished by implementing the model in a common computing tool such as Microsoft Excel. Excel is readily available and accessible to most system analysts, but it is not designed for straightforward implementation of a Monte Carlo–based method. Using a Monte Carlo algorithm requires in-spreadsheet scripting and statistical analyses or the use of add-ons such as Crystal Ball. An alternative method uses propagation of error calculations in the existing Excel-based system to estimate system cost uncertainty. This method has the advantage of using Microsoft Excel as is, but it requires the use of simplifying assumptions. These assumptions do not necessarily bring into question the analytical results. In fact, the

  4. A statistical mechanical model of economics

    NASA Astrophysics Data System (ADS)

    Lubbers, Nicholas Edward Williams

    Statistical mechanics pursues low-dimensional descriptions of systems with a very large number of degrees of freedom. I explore this theme in two contexts. The main body of this dissertation explores and extends the Yard Sale Model (YSM) of economic transactions using a combination of simulations and theory. The YSM is a simple interacting model for wealth distributions which has the potential to explain the empirical observation of Pareto distributions of wealth. I develop the link between wealth condensation and the breakdown of ergodicity due to nonlinear diffusion effects which are analogous to the geometric random walk. Using this, I develop a deterministic effective theory of wealth transfer in the YSM that is useful for explaining many quantitative results. I introduce various forms of growth to the model, paying attention to the effect of growth on wealth condensation, inequality, and ergodicity. Arithmetic growth is found to partially break condensation, and geometric growth is found to completely break condensation. Further generalizations of geometric growth with growth in- equality show that the system is divided into two phases by a tipping point in the inequality parameter. The tipping point marks the line between systems which are ergodic and systems which exhibit wealth condensation. I explore generalizations of the YSM transaction scheme to arbitrary betting functions to develop notions of universality in YSM-like models. I find that wealth vi condensation is universal to a large class of models which can be divided into two phases. The first exhibits slow, power-law condensation dynamics, and the second exhibits fast, finite-time condensation dynamics. I find that the YSM, which exhibits exponential dynamics, is the critical, self-similar model which marks the dividing line between the two phases. The final chapter develops a low-dimensional approach to materials microstructure quantification. Modern materials design harnesses complex

  5. Economics of sugar production with Trichoderma reesei Rutgers C-30

    SciTech Connect

    Perez, J.; Wilke, C.R.; Blanch, H.W.

    1980-08-01

    The economics of sugar production from bioconversion of corn stover utilizing cellulase obtained from Trichoderma reesei strain Rutgers C-30 were investigated. The cost of manufacturing sugar is 10.5 cents per pound. This reduced cost is due to cellulase activities ranging from 7 to 14 IU/ml from batch cultures and from 3.5 to 6 IU/ml from continuous cultures. Hydrolysis can be carried out at substrate concentrations up to 25% and give product streams containing up to 15% sugars. This corresponds to a maximum yield of 86%. A sensitivity analysis indicates that sugar can be produced at near competitive prices from corn stover costing $0 to $50 per ton. By utilizing new fermentation technology, sugar at these prices can be used to produce 95% alcohol at a cost ranging from $1.80 to $3.00 per gallon.

  6. A Model for Rural Economic Development.

    ERIC Educational Resources Information Center

    Rampp, Lary; Johnson, Deke

    This paper offers definitions and descriptions, and explores the dynamics, of "strategic grantseeking" as a means of supporting economic development programs. Strategic grantseeking is a natural and dynamic tool usable with any economic development program. It consists of a set of concepts, procedures, and tools which are integrated into…

  7. An Economic Model of Interpersonal Communication.

    ERIC Educational Resources Information Center

    Cissna, Linda Surbaugh; Cissna, Kenneth N.

    A Marxian economic analysis of interpersonal communication within a capitalist system finds that capitalism, with its attendant stress on wholly economic values, produces a commodity-oriented society. Mass media advertising is the primary vehicle through which the capitalist culture indoctrinates the ideas of competition for the intangibles (love,…

  8. Annual Economic Burden of Productivity Losses Among Adult Survivors of Childhood Cancers.

    PubMed

    Guy, Gery P; Berkowitz, Zahava; Ekwueme, Donatus U; Rim, Sun Hee; Yabroff, K Robin

    2016-11-01

    Although adult survivors of childhood cancers have poorer health and greater health limitations than other adults, substantial gaps remain in understanding the economic consequences of surviving childhood cancer. Therefore, we estimated the economic burden of productivity losses among adult survivors of childhood cancers. We examined health status, functional limitations, and productivity loss among adult survivors of childhood cancers (n = 239) diagnosed at ≤14 years of age compared with adults without a history of cancer (n = 304 265) by using the 2004-2014 National Health Interview Survey. We estimated economic burden using the productivity loss from health-related unemployment, missed work days, missed household productivity, and multivariable regression models controlling for age, sex, race/ethnicity, education, comorbidities, and survey year. Childhood cancer survivorship is associated with a substantial economic burden. Adult survivors of childhood cancers are more likely to be in poorer health, need assistance with personal care and routine needs, have work limitations, be unable to work because of health, miss more days of work, and have greater household productivity loss compared with adults without a history of cancer (all P < .05). The annual productivity loss for adult survivors of childhood cancer is $8169 per person compared with $3083 per person for individuals without a history of cancer. These findings underscore the importance of efforts to reduce the health and economic burden among adult survivors of childhood cancer. In addition, this study highlights the potential productivity losses that could be avoided during adulthood from the prevention of childhood cancer in the United States. Copyright © 2016 by the American Academy of Pediatrics.

  9. Economic costs of chronic disease through lost productive life years (PLYs) among Australians aged 45-64 years from 2015 to 2030: results from a microsimulation model.

    PubMed

    Schofield, Deborah; Shrestha, Rupendra N; Cunich, Michelle M; Tanton, Robert; Veerman, Lennert; Kelly, Simon J; Passey, Megan E

    2016-09-22

    To project the number of older workers with lost productive life years (PLYs) due to chronic disease and resultant lost income; and lost taxes and increased welfare payments from 2015 to 2030. Using a microsimulation model, Health&WealthMOD2030, the costs of chronic disease in Australians aged 45-64 were projected to 2030. The model integrates household survey data from the Australian Bureau of Statistics Surveys of Disability, Ageing and Carers (SDACs) 2003 and 2009, output from long-standing microsimulation models (STINMOD (Static Incomes Model) and APPSIM (Australian Population and Policy Simulation Model)) used by various government departments, population and labour force growth data from Treasury, and disease trends data from the Australian Burden of Disease and Injury Study (2003). Respondents aged 45-64 years in the SDACs 2003 and 2009 formed the base population. Lost PLYs due to chronic disease; resultant lost income, lost taxes and increased welfare payments in 2015, 2020, 2025 and 2030. We projected 380 000 (6.4%) people aged 45-64 years with lost PLYs in 2015, increasing to 462 000 (6.5%) in 2030-a 22% increase in absolute numbers. Those with lost PLYs experience the largest reduction in income than any other group in each year compared to those employed full time without a chronic disease, and this income gap widens over time. The total economic loss due to lost PLYs consisted of lost income modelled at $A12.6 billion in 2015, increasing to $A20.5 billion in 2030-a 62.7% increase. Additional costs to the government consisted of increased welfare payments at $A6.2 billion in 2015, increasing to $A7.3 billion in 2030-a 17.7% increase; and a loss of $A3.1 billion in taxes in 2015, increasing to $A4.7 billion in 2030-a growth of 51.6%. There is a need for greater investment in effective preventive health interventions which improve workers' health and work capacity. Published by the BMJ Publishing Group Limited. For permission to use (where not

  10. Essays on Applied Resource Economics Using Bioeconomic Optimization Models

    NASA Astrophysics Data System (ADS)

    Affuso, Ermanno

    With rising demographic growth, there is increasing interest in analytical studies that assess alternative policies to provide an optimal allocation of scarce natural resources while ensuring environmental sustainability. This dissertation consists of three essays in applied resource economics that are interconnected methodologically within the agricultural production sector of Economics. The first chapter examines the sustainability of biofuels by simulating and evaluating an agricultural voluntary program that aims to increase the land use efficiency in the production of biofuels of first generation in the state of Alabama. The results show that participatory decisions may increase the net energy value of biofuels by 208% and reduce emissions by 26%; significantly contributing to the state energy goals. The second chapter tests the hypothesis of overuse of fertilizers and pesticides in U.S. peanut farming with respect to other inputs and address genetic research to reduce the use of the most overused chemical input. The findings suggest that peanut producers overuse fungicide with respect to any other input and that fungi resistant genetically engineered peanuts may increase the producer welfare up to 36.2%. The third chapter implements a bioeconomic model, which consists of a biophysical model and a stochastic dynamic recursive model that is used to measure potential economic and environmental welfare of cotton farmers derived from a rotation scheme that uses peanut as a complementary crop. The results show that the rotation scenario would lower farming costs by 14% due to nitrogen credits from prior peanut land use and reduce non-point source pollution from nitrogen runoff by 6.13% compared to continuous cotton farming.

  11. Optimizing cultivation of agricultural products using socio-economic and environmental scenarios.

    PubMed

    RaheliNamin, Behnaz; Mortazavi, Samar; Salmanmahiny, Abdolrassoul

    2016-11-01

    The combination of degrading natural conditions and resources, climate change, growing population, urban development, and competition in a global market complicate optimization of land for agricultural products. The use of pesticides and fertilizers for crop production in the agricultural fields has become excessive in the recent years and Golestan Province of Iran is no exception in this regard. For this, effective management with an efficient and cost-effective practice should be undertaken, maintaining public service at a high level and preserving the environment. Improving the production efficiency of agriculture, efficient use of water resources, decreasing the use of pesticides and fertilizers, improving farmer revenue, and conservation of natural resources are the main objectives of the allocation, ranking, and optimization of agricultural products. The goal of this paper is to use an optimization procedure to lower the negative effects of agriculture while maintaining a high production rate, which is currently a gap in the study area. We collected information about fertilizer and pesticide consumption and other data in croplands of eastern Golestan Province through face-to-face interviews with farmers to optimize cultivation of the agricultural products. The toxicity of pesticides according to LD50 was also included in the optimization model. A decision-support software system called multiple criteria analysis tool was used to simultaneously minimize consumption of water, chemical fertilizers, and pesticides and maximize socio-economic returns. Three scenarios for optimization of agricultural products were generated that alternatively emphasized on environmental and socio-economic goals. Comparing socio-economic and environmental performance of the optimized agricultural products under the three scenarios illustrated the conflict between social, economic, and environmental objectives. Of the six crops studied (wheat, barley, rice, soybeans, oilseed rape

  12. Economic contract theory tests models of mutualism.

    PubMed

    Weyl, E Glen; Frederickson, Megan E; Yu, Douglas W; Pierce, Naomi E

    2010-09-07

    Although mutualisms are common in all ecological communities and have played key roles in the diversification of life, our current understanding of the evolution of cooperation applies mostly to social behavior within a species. A central question is whether mutualisms persist because hosts have evolved costly punishment of cheaters. Here, we use the economic theory of employment contracts to formulate and distinguish between two mechanisms that have been proposed to prevent cheating in host-symbiont mutualisms, partner fidelity feedback (PFF) and host sanctions (HS). Under PFF, positive feedback between host fitness and symbiont fitness is sufficient to prevent cheating; in contrast, HS posits the necessity of costly punishment to maintain mutualism. A coevolutionary model of mutualism finds that HS are unlikely to evolve de novo, and published data on legume-rhizobia and yucca-moth mutualisms are consistent with PFF and not with HS. Thus, in systems considered to be textbook cases of HS, we find poor support for the theory that hosts have evolved to punish cheating symbionts; instead, we show that even horizontally transmitted mutualisms can be stabilized via PFF. PFF theory may place previously underappreciated constraints on the evolution of mutualism and explain why punishment is far from ubiquitous in nature.

  13. Economic contract theory tests models of mutualism

    PubMed Central

    Weyl, E. Glen; Frederickson, Megan E.; Yu, Douglas W.; Pierce, Naomi E.

    2010-01-01

    Although mutualisms are common in all ecological communities and have played key roles in the diversification of life, our current understanding of the evolution of cooperation applies mostly to social behavior within a species. A central question is whether mutualisms persist because hosts have evolved costly punishment of cheaters. Here, we use the economic theory of employment contracts to formulate and distinguish between two mechanisms that have been proposed to prevent cheating in host–symbiont mutualisms, partner fidelity feedback (PFF) and host sanctions (HS). Under PFF, positive feedback between host fitness and symbiont fitness is sufficient to prevent cheating; in contrast, HS posits the necessity of costly punishment to maintain mutualism. A coevolutionary model of mutualism finds that HS are unlikely to evolve de novo, and published data on legume–rhizobia and yucca–moth mutualisms are consistent with PFF and not with HS. Thus, in systems considered to be textbook cases of HS, we find poor support for the theory that hosts have evolved to punish cheating symbionts; instead, we show that even horizontally transmitted mutualisms can be stabilized via PFF. PFF theory may place previously underappreciated constraints on the evolution of mutualism and explain why punishment is far from ubiquitous in nature. PMID:20733067

  14. Proof of Economic Viability of Blended Learning Business Models

    ERIC Educational Resources Information Center

    Druhmann, Carsten; Hohenberg, Gregor

    2014-01-01

    The discussion on economically sustainable business models with respect to information technology is lacking in many aspects of proven approaches. In the following contribution the economic viability is valued based on a procedural model for design and evaluation of e-learning business models in the form of a case study. As a case study object a…

  15. Modeling of the Gross Regional Product on the Basis of Production Functions

    ERIC Educational Resources Information Center

    Sadovin, Nikolay S.; Kokotkina, Tatiana N.; Barkalova, Tatiana G.; Tsaregorodsev, Evgeny I.

    2016-01-01

    The article is devoted to elaboration and construction of a static model of macroeconomics in which economics is considered as an unstructured holistic unit, the input of which receives the resources, and the output is the result of the functioning of economics in the form of gross domestic product or gross regional product. Resources are…

  16. Manufacturing economic outlook for production of electric vehicle

    SciTech Connect

    Patten, J.A.; Murthy, M.; Cheung, N.N.Y.; Hartgen, D.T.

    1994-12-31

    Results of a study on the manufacturing of components of electric vehicles (EVs) in North Carolina are reported. Data are obtained from a consumer survey to ascertain the level of customer interest in EVs, coupled with data related to automobile manufacturing. The model uses input/output analysis for the EV manufacturing sector. An estimate is also made of the value of the potential economic impact (salaries of employees) of NC`s share of the total US manufacturing of EVs. The total US manufacturing effort for EVs was evaluated at the present California mandated levels of 2, 5 and 10% levels. This analysis indicates the NC manufacturing economic impact to be $8.6--$86 million annually, over the range of number of vehicles and vehicle cost. The range of the NC economic impacts went from a loss of $2--$10 million in carburators, pistons and rings to a gain of $19--$95 million for electric motors/generators. The above points out significant and potentially negative impact of EVs for certain automobile component industries. This suggests that in regions not participating in the development of EV manufacturing, the potential loss of manufacturing (due to the replacement of internal combustion engine vehicles by EVs) could be substantial. Suggestions are made to reduce this impact.

  17. Assessing the Economic Viability of Bio-based Products for Missouri Value-added Crop Production

    SciTech Connect

    Nicholas Kalaitzandonakes

    2005-11-30

    While research and development on biobased products has continued strong over the years, parallel attention on the economics and management of such product innovation has been lacking. With the financial support of the Department of Energy, the Economics and Management of Agrobiotechnology Center at the University of Missouri-Columbia has launched a pilot graduate education program that seeks to fill the gap. Within this context, a multi-disciplinary research and teaching program has been structured with an emphasis on new product and innovation economics and management. More specifically, this pilot graduate education program has the following major objectives: (1) To provide students with a strong background in innovation economics, management, and strategy. (2) To diversify the students academic background with coursework in science and technology. (3) To familiarize the student with biobased policy initiatives through interaction with state and national level organizations and policymakers. (4) To facilitate active collaboration with industry involved in the development and production of biobased products. The pilot education program seeks to develop human capital and research output. Although the research is, initially, focused on issues related to the State of Missouri, the results are expected to have national implications for the economy, producers, consumers and environment.

  18. Global economic burden of Chagas disease: a computational simulation model

    PubMed Central

    Lee, Bruce Y; Bacon, Kristina M; Bottazzi, Maria Elena; Hotez, Peter J

    2013-01-01

    Summary Background As Chagas disease continues to expand beyond tropical and subtropical zones, a growing need exists to better understand its resulting economic burden to help guide stakeholders such as policy makers, funders, and product developers. We developed a Markov simulation model to estimate the global and regional health and economic burden of Chagas disease from the societal perspective. Methods Our Markov model structure had a 1 year cycle length and consisted of five states: acute disease, indeterminate disease, cardiomyopathy with or without congestive heart failure, megaviscera, and death. Major model parameter inputs, including the annual probabilities of transitioning from one state to another, and present case estimates for Chagas disease came from various sources, including WHO and other epidemiological and disease-surveillance-based reports. We calculated annual and lifetime health-care costs and disability-adjusted life-years (DALYs) for individuals, countries, and regions. We used a discount rate of 3% to adjust all costs and DALYs to present-day values. Findings On average, an infected individual incurs US$474 in health-care costs and 0·51 DALYs annually. Over his or her lifetime, an infected individual accrues an average net present value of $3456 and 3·57 DALYs. Globally, the annual burden is $627·46 million in health-care costs and 806 170 DALYs. The global net present value of currently infected individuals is $24·73 billion in health-care costs and 29 385 250 DALYs. Conversion of this burden into costs results in annual per-person costs of $4660 and lifetime per-person costs of $27 684. Global costs are $7·19 billion per year and $188·80 billion per lifetime. More than 10% of these costs emanate from the USA and Canada, where Chagas disease has not been traditionally endemic. A substantial proportion of the burden emerges from lost productivity from cardiovascular disease-induced early mortality. Interpretation The economic burden

  19. Scale-up and economic analysis of biodiesel production from municipal primary sewage sludge.

    PubMed

    Olkiewicz, Magdalena; Torres, Carmen M; Jiménez, Laureano; Font, Josep; Bengoa, Christophe

    2016-08-01

    Municipal wastewater sludge is a promising lipid feedstock for biodiesel production, but the need to eliminate the high water content before lipid extraction is the main limitation for scaling up. This study evaluates the economic feasibility of biodiesel production directly from liquid primary sludge based on experimental data at laboratory scale. Computational tools were used for the modelling of the process scale-up and the different configurations of lipid extraction to optimise this step, as it is the most expensive. The operational variables with a major influence in the cost were the extraction time and the amount of solvent. The optimised extraction process had a break-even price of biodiesel of 1232 $/t, being economically competitive with the current cost of fossil diesel. The proposed biodiesel production process from waste sludge eliminates the expensive step of sludge drying, lowering the biodiesel price.

  20. Metropolitan and state economic regions (MASTER) model - overview

    SciTech Connect

    Adams, R.C.; Moe, R.J.; Scott, M.J.

    1983-05-01

    The Metropolitan and State Economic Regions (MASTER) model is a unique multi-regional economic model designed to forecast regional economic activity and assess the regional economic impacts caused by national and regional economic changes (e.g., interest rate fluctuations, energy price changes, construction and operation of a nuclear waste storage facility, shutdown of major industrial operations). MASTER can be applied to any or all of the 268 Standard Metropolitan Statistical Areas (SMSAs) and 48 non-SMSA rest-of-state-areas (ROSAs) in the continental US. The model can also be applied to any or all of the continental US counties and states. This report is divided into four sections: capabilities and applications of the MASTER model, development of the model, model simulation, and validation testing.

  1. The global historical and future economic loss and cost of earthquakes during the production of adaptive worldwide economic fragility functions

    NASA Astrophysics Data System (ADS)

    Daniell, James; Wenzel, Friedemann

    2014-05-01

    macroseismic intensity, capital stock estimate, GDP estimate, year and the combined seismic building index (a created combination of the global seismic code index, building practice factor, building age and infrastructure vulnerability). The analysis provided three key results: a) The production of economic fragility functions from the 1900-2008 events showed very good correlation to the economic loss and cost from earthquakes from 2009-2013, in real-time. This methodology has been extended to other natural disaster types (typhoon, flood, drought). b) The reanalysis of historical earthquake events in order to check associated historical loss and costs versus the expected exposure in terms of intensities. The 1939 Chillan, 1948 Turkmenistan, 1950 Iran, 1972 Managua, 1980 Western Nepal and 1992 Erzincan earthquake events were seen as huge outliers compared with the modelled capital stock and GDP and thus additional studies were undertaken to check the original loss results. c) A worldwide GIS layer database of capital stock (gross and net), GDP, infrastructure age and economic indices over the period 1900-2013 have been created in conjunction with the CATDAT database in order to define correct economic loss and costs.

  2. Projecting county pulpwood production with historical production and macro-economic variables

    Treesearch

    Consuelo Brandeis; Dayton M. Lambert

    2014-01-01

    We explored forecasting of county roundwood pulpwood produc-tion with county-vector autoregressive (CVAR) and spatial panelvector autoregressive (SPVAR) methods. The analysis used timberproducts output data for the state of Florida, together with a set ofmacro-economic variables. Overall, we found the SPVAR specifica-tion produced forecasts with lower error rates...

  3. Production of butyl solvents from lignocellulose: An economic analysis

    SciTech Connect

    Wright, J D; Daling, R; Sandel, R L; Fitzpatrick, S W

    1986-11-01

    A process is described that produces butyl solvents, butanol, isopropanol, and ethanol from wood or other lignocellulosic feedstock. Two new elements of technology introduced are the processing batch reactor developed at SERI that produces high yields of fermentable sugars (hexoses and pentoses) at the appropriate concentration for the butyl solvents fermentation and a novel method of separating products using liquid-liquid extraction, which reduces the separation energy required to about 30% of energy required in the conventional batch method. Economic analysis suggests that the project is attractive at a feedstock capacity of 400,000 dry MTA or larger (178 million lb/yr solvents). There are, however, uncertainties associated with the project because of the relatively early stage of development of the key elements of the process technology and the sensitivity of the DCFIROR to estimated capital cost. A further conclusion is that the process economics would benefit greatly from reduced capital cost of the fermentation section. This could perhaps be accomplished by developing a continuous fermentation process. Such fermentation technology has been demonstrated on laboratory scale, but as far as is known, has not been developed to pilot scale. 21 refs., 4 figs., 3 tabs.

  4. Black liquor fractionation for biofuels production - a techno-economic assessment.

    PubMed

    Mesfun, Sennai; Lundgren, Joakim; Grip, Carl-Erik; Toffolo, Andrea; Nilsson, Rasika Lasanthi Kudahettige; Rova, Ulrika

    2014-08-01

    The hemicelluloses fraction of black liquor is an underutilized resource in many chemical pulp mills. It is possible to extract and separate the lignin and hemicelluloses from the black liquor and use the hemicelluloses for biochemical conversion into biofuels and chemicals. Precipitation of the lignin from the black liquor would consequently decrease the thermal load on the recovery boiler, which is often referred to as a bottleneck for increased pulp production. The objective of this work is to techno-economically evaluate the production of sodium-free lignin as a solid fuel and butanol to be used as fossil gasoline replacement by fractionating black liquor. The hydrolysis and fermentation processes are modeled in Aspen Plus to analyze energy and material balances as well as to evaluate the plant economics. A mathematical model of an existing pulp and paper mill is used to analyze the effects on the energy performance of the mill subprocesses.

  5. An economic order quantity model with shortage and inflation

    NASA Astrophysics Data System (ADS)

    Wulan, Elis Ratna; Nurjaman, Wildan

    2015-09-01

    The effect of inflation has become a persistent characteristic and more significant problem of many developing economies especially in the third world countries. While making effort to achieve optimal quantity of product to be produced or purchased using the simplest and on the shelf classical EOQ model, the non-inclusion of conflicting economic realities as shortage and inflation has rendered its result quite uneconomical and hence the purpose for this study. Mathematical expression was developed for each of the cost components the sum of which become the total inventory model over the period (0,L) ((TIC(0,L)). L is planning horizon and TIC(0,L) is total inventory cost over a period of (0,L). Significant savings with increase in quantity was achieved based on deference in the varying price regime. With the assumptions considered and subject to the availability of reliable inventory cost element, the developed model is found to produce a feasible, and economic inventory stock-level with the numerical example of a material supply of a manufacturing company.

  6. Supercritical biodiesel production and power cogeneration: technical and economic feasibilities.

    PubMed

    Deshpande, A; Anitescu, G; Rice, P A; Tavlarides, L L

    2010-03-01

    An integrated supercritical fluid technology with power cogeneration to produce biodiesel fuels, with no need for the costly separations involved with the conventional technology, is proposed, documented for technical and economic feasibility, and preliminarily designed. The core of the integrated system consists of the transesterification of various triglyceride sources (e.g., vegetable oils and animal fats) with supercritical methanol/ethanol. Part of the reaction products can be combusted by a diesel power generator integrated in the system which, in turn, provides the power needed to pressurize the system and the heat of the exhaust gases necessary in the transesterification step. The latter energy demand can also be satisfied by a fired heater, especially for higher plant capacities. Different versions of this system can be implemented based on the main target of the technology: biodiesel production or diesel engine applications, including power generation. The process options considered for biodiesel fuel production estimate break-even processing costs of biodiesel as low as $0.26/gal ($0.07/L) with a diesel power generator and $0.35/gal ($0.09/L) with a fired heater for a plant capacity of 15,000 gal/day (56,775 L/day). Both are significantly lower than the current processing costs of approximately $0.51/gal ($0.13/L) of biodiesel produced by conventional catalytic methods. A retail cost of biodiesel produced by the proposed method is likely to be competitive with the prices of diesel fuels.

  7. Economic costs of chronic disease through lost productive life years (PLYs) among Australians aged 45–64 years from 2015 to 2030: results from a microsimulation model

    PubMed Central

    Schofield, Deborah; Shrestha, Rupendra N; Cunich, Michelle M; Tanton, Robert; Veerman, Lennert; Kelly, Simon J

    2016-01-01

    Objectives To project the number of older workers with lost productive life years (PLYs) due to chronic disease and resultant lost income; and lost taxes and increased welfare payments from 2015 to 2030. Design, setting and participants Using a microsimulation model, Health&WealthMOD2030, the costs of chronic disease in Australians aged 45–64 were projected to 2030. The model integrates household survey data from the Australian Bureau of Statistics Surveys of Disability, Ageing and Carers (SDACs) 2003 and 2009, output from long-standing microsimulation models (STINMOD (Static Incomes Model) and APPSIM (Australian Population and Policy Simulation Model)) used by various government departments, population and labour force growth data from Treasury, and disease trends data from the Australian Burden of Disease and Injury Study (2003). Respondents aged 45–64 years in the SDACs 2003 and 2009 formed the base population. Main outcome measures Lost PLYs due to chronic disease; resultant lost income, lost taxes and increased welfare payments in 2015, 2020, 2025 and 2030. Results We projected 380 000 (6.4%) people aged 45–64 years with lost PLYs in 2015, increasing to 462 000 (6.5%) in 2030—a 22% increase in absolute numbers. Those with lost PLYs experience the largest reduction in income than any other group in each year compared to those employed full time without a chronic disease, and this income gap widens over time. The total economic loss due to lost PLYs consisted of lost income modelled at $A12.6 billion in 2015, increasing to $A20.5 billion in 2030—a 62.7% increase. Additional costs to the government consisted of increased welfare payments at $A6.2 billion in 2015, increasing to $A7.3 billion in 2030—a 17.7% increase; and a loss of $A3.1 billion in taxes in 2015, increasing to $A4.7 billion in 2030—a growth of 51.6%. Conclusions There is a need for greater investment in effective preventive health interventions which improve workers’ health

  8. Stokes integral of economic growth. Calculus and the Solow model

    NASA Astrophysics Data System (ADS)

    Mimkes, Jürgen

    2010-04-01

    Economic growth depends on capital and labor and two-dimensional calculus has been applied to economic theory. This leads to Riemann and Stokes integrals and to the first and second laws of production and growth. The mathematical structure is the same as in thermodynamics, economic properties may be related to physical terms: capital to energy, production to physical work, GDP per capita to temperature, production function to entropy. This is called econophysics. Production, trade and banking may be compared to motors, heat pumps or refrigerators. The Carnot process of the first law creates two levels in each system: cold and hot in physics; buyer and seller, investor and saver, rich and poor in economics. The efficiency rises with the income difference of rich and poor. The results of econophysics are compared to neoclassical theory.

  9. Artemisinin resistance--modelling the potential human and economic costs.

    PubMed

    Lubell, Yoel; Dondorp, Arjen; Guérin, Philippe J; Drake, Tom; Meek, Sylvia; Ashley, Elizabeth; Day, Nicholas P J; White, Nicholas J; White, Lisa J

    2014-11-23

    Artemisinin combination therapy is recommended as first-line treatment for falciparum malaria across the endemic world and is increasingly relied upon for treating vivax malaria where chloroquine is failing. Artemisinin resistance was first detected in western Cambodia in 2007, and is now confirmed in the Greater Mekong region, raising the spectre of a malaria resurgence that could undo a decade of progress in control, and threaten the feasibility of elimination. The magnitude of this threat has not been quantified. This analysis compares the health and economic consequences of two future scenarios occurring once artemisinin-based treatments are available with high coverage. In the first scenario, artemisinin combination therapy (ACT) is largely effective in the management of uncomplicated malaria and severe malaria is treated with artesunate, while in the second scenario ACT are failing at a rate of 30%, and treatment of severe malaria reverts to quinine. The model is applied to all malaria-endemic countries using their specific estimates for malaria incidence, transmission intensity and GDP. The model describes the direct medical costs for repeated diagnosis and retreatment of clinical failures as well as admission costs for severe malaria. For productivity losses, the conservative friction costing method is used, which assumes a limited economic impact for individuals that are no longer economically active until they are replaced from the unemployment pool. Using conservative assumptions and parameter estimates, the model projects an excess of 116,000 deaths annually in the scenario of widespread artemisinin resistance. The predicted medical costs for retreatment of clinical failures and for management of severe malaria exceed US$32 million per year. Productivity losses resulting from excess morbidity and mortality were estimated at US$385 million for each year during which failing ACT remained in use as first-line treatment. These 'ballpark' figures for the

  10. 50 CFR Table 3c to Part 680 - Crab Product Codes for Economic Data Reports

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Crab Product Codes for Economic Data... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 680, Table 3c Table 3c to Part 680—Crab Product Codes for Economic Data Reports Code Description 01 Whole crab. 80 Sections. 81 Meats. 97 Other (specify). ...

  11. 50 CFR Table 3c to Part 680 - Crab Product Codes for Economic Data Reports

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Crab Product Codes for Economic Data... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 680, Table 3c Table 3c to Part 680—Crab Product Codes for Economic Data Reports Code Description 01 Whole crab. 80 Sections. 81 Meats. 97 Other (specify). ...

  12. 50 CFR Table 3c to Part 680 - Crab Product Codes for Economic Data Reports

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Crab Product Codes for Economic Data... EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 680, Table 3c Table 3c to Part 680—Crab Product Codes for Economic Data Reports Code Description 01 Whole crab. 80 Sections. 81 Meats. 97 Other (specify). ...

  13. Economic implications of Japan's aging population: a macro-economic demographic modeling approach.

    PubMed

    Ogawa, N

    1982-01-01

    This paper utilizes a macroeconomic demographic model to analyze the probable impact of population aging on various public programs in Japan. Rapid fertility decline aided by mortality decline has caused the proportion of the Japanese population aged 65 and over to increase from 4.9% in 1950 to 9.0% in 1980. A population projection based on the 1975 population census assumes a recovery of fertility from a total fertility rate (TFR) of 1.9 in 1976 to 2.16 in 1980 and a gradual decline to 2.1 by 1987, while an alternative projection assumes a continuing fertility decline to a TFR of 1.65 in 2025. According to these assumptions, in 2025 18.12% to 21.29% of the total population would be aged 65 or over and 38.66% to 43.80% of the working age population would be aged 45-64. A macroeconomic neoclassical growth model with some Keynesian features was formulated to evaluate the future impact of population aging on social security programs. Population changes are transmitted to economic variables in the model through the supply of labor, level of savings, public health care plans, and old-age pension schemes. The simulation experiments included the 2 population projections and 2 alternative production functions, 1 with the quality of labor incorporated and 1 without. The results indicated that, regardless of the population projection and production function used, the growth of the economy is likely to slow to 1 or 0% in the beginning of the next century due to decreased growth of the labor force and a change in its quality due to age-compositional variations. Public health insurance schemes and pension plans will require increasing financial resources as a result of accelerated population aging; depending on the choice of benefit levels, the proportion of national income allocated to them is expected to range from 14%-40% in the year 2010. Per capita gross national product will continue to grow despite decreased economic growth, but savings might be adversely affected if the

  14. TOWARD EFFICIENT RIPARIAN RESTORATION: INTEGRATING ECONOMIC, PHYSICAL, AND BIOLOGICAL MODELS

    EPA Science Inventory

    This paper integrates economic, biological, and physical models to determine the efficient combination and spatial allocation of conservation efforts for water quality protection and salmonid habitat enhancement in the Grande Ronde basin, Oregon. The integrated modeling system co...

  15. TOWARD EFFICIENT RIPARIAN RESTORATION: INTEGRATING ECONOMIC, PHYSICAL, AND BIOLOGICAL MODELS

    EPA Science Inventory

    This paper integrates economic, biological, and physical models to determine the efficient combination and spatial allocation of conservation efforts for water quality protection and salmonid habitat enhancement in the Grande Ronde basin, Oregon. The integrated modeling system co...

  16. Economic modeling and energy policy planning. [technology transfer, market research

    NASA Technical Reports Server (NTRS)

    Thompson, R. G.; Schwartz, A., Jr.; Lievano, R. J.; Stone, J. C.

    1974-01-01

    A structural economic model is presented for estimating the demand functions for natural gas and crude oil in industry and in steam electric power generation. Extensions of the model to other commodities are indicated.

  17. A Note on Simulation Models in the Economics Classroom.

    ERIC Educational Resources Information Center

    Day, Edward

    1987-01-01

    Describes the disadvantages of using "canned" simulations as a part of an undergraduate economics course. Identifies four advantages of having students develop their own computer simulation models. Outlines the model-building process and displays a sample program. (JDH)

  18. Economic modeling and energy policy planning. [technology transfer, market research

    NASA Technical Reports Server (NTRS)

    Thompson, R. G.; Schwartz, A., Jr.; Lievano, R. J.; Stone, J. C.

    1974-01-01

    A structural economic model is presented for estimating the demand functions for natural gas and crude oil in industry and in steam electric power generation. Extensions of the model to other commodities are indicated.

  19. Techno-Economic Analysis of Biochemical Scenarios for Production of Cellulosic Ethanol

    SciTech Connect

    Kazi, F. K.; Fortman, J.; Anex, R.; Kothandaraman, G.; Hsu, D.; Aden, A.; Dutta, A.

    2010-06-01

    A techno-economic analysis on the production of cellulosic ethanol by fermentation was conducted to understand the viability of liquid biofuel production processes within the next 5-8 years. Initially, 35 technologies were reviewed, then a two-step down selection was performed to choose scenarios to be evaluated in a more detailed economic analysis. The lignocellulosic ethanol process was selected because it is well studied and portions of the process have been tested at pilot scales. Seven process variations were selected and examined in detail. Process designs were constrained to public data published in 2007 or earlier, without projecting for future process improvements. Economic analysis was performed for an 'nth plant' (mature technology) to obtain total investment and product value (PV). Sensitivity analysis was performed on PV to assess the impact of variations in process and economic parameters. Results show that the modeled dilute acid pretreatment process without any downstream process variation had the lowest PV of $3.40/gal of ethanol ($5.15/gallon of gasoline equivalent) in 2007 dollars. Sensitivity analysis shows that PV is most sensitive to feedstock and enzyme costs.

  20. Economic evaluation in chronic pain: a systematic review and de novo flexible economic model.

    PubMed

    Sullivan, W; Hirst, M; Beard, S; Gladwell, D; Fagnani, F; López Bastida, J; Phillips, C; Dunlop, W C N

    2016-07-01

    There is unmet need in patients suffering from chronic pain, yet innovation may be impeded by the difficulty of justifying economic value in a field beset by data limitations and methodological variability. A systematic review was conducted to identify and summarise the key areas of variability and limitations in modelling approaches in the economic evaluation of treatments for chronic pain. The results of the literature review were then used to support the development of a fully flexible open-source economic model structure, designed to test structural and data assumptions and act as a reference for future modelling practice. The key model design themes identified from the systematic review included: time horizon; titration and stabilisation; number of treatment lines; choice/ordering of treatment; and the impact of parameter uncertainty (given reliance on expert opinion). Exploratory analyses using the model to compare a hypothetical novel therapy versus morphine as first-line treatments showed cost-effectiveness results to be sensitive to structural and data assumptions. Assumptions about the treatment pathway and choice of time horizon were key model drivers. Our results suggest structural model design and data assumptions may have driven previous cost-effectiveness results and ultimately decisions based on economic value. We therefore conclude that it is vital that future economic models in chronic pain are designed to be fully transparent and hope our open-source code is useful in order to aspire to a common approach to modelling pain that includes robust sensitivity analyses to test structural and parameter uncertainty.

  1. Approach and development strategy for an agent-based model of economic confidence.

    SciTech Connect

    Sprigg, James A.; Pryor, Richard J.; Jorgensen, Craig Reed

    2004-08-01

    We are extending the existing features of Aspen, a powerful economic modeling tool, and introducing new features to simulate the role of confidence in economic activity. The new model is built from a collection of autonomous agents that represent households, firms, and other relevant entities like financial exchanges and governmental authorities. We simultaneously model several interrelated markets, including those for labor, products, stocks, and bonds. We also model economic tradeoffs, such as decisions of households and firms regarding spending, savings, and investment. In this paper, we review some of the basic principles and model components and describe our approach and development strategy for emulating consumer, investor, and business confidence. The model of confidence is explored within the context of economic disruptions, such as those resulting from disasters or terrorist events.

  2. [Decision modeling for economic evaluation of health technologies].

    PubMed

    de Soárez, Patrícia Coelho; Soares, Marta Oliveira; Novaes, Hillegonda Maria Dutilh

    2014-10-01

    Most economic evaluations that participate in decision-making processes for incorporation and financing of technologies of health systems use decision models to assess the costs and benefits of the compared strategies. Despite the large number of economic evaluations conducted in Brazil, there is a pressing need to conduct an in-depth methodological study of the types of decision models and their applicability in our setting. The objective of this literature review is to contribute to the knowledge and use of decision models in the national context of economic evaluations of health technologies. This article presents general definitions about models and concerns with their use; it describes the main models: decision trees, Markov chains, micro-simulation, simulation of discrete and dynamic events; it discusses the elements involved in the choice of model; and exemplifies the models addressed in national economic evaluation studies of diagnostic and therapeutic preventive technologies and health programs.

  3. Folding Our Way to Productivity. Active Learning Lessons. Economics International.

    ERIC Educational Resources Information Center

    Baranova, Daira; Bottomoley, Alice; Brock, John; Shappo, Natalia

    This lesson plan was developed through "Economics International," an international program to help build economic education infrastructures in the emerging market economies. It provides a lesson description; economic concepts; content standards and benchmarks; related subject areas; instructional objectives; time required for lesson…

  4. The Production, Consumption and Distribution of Economic Podcasts

    ERIC Educational Resources Information Center

    Swan, Kathy; Hofer, Mark; Swan, Gerry; Mazur, Joan

    2010-01-01

    Podcasting remains one of the hot "buzz words" in technology today--both in and out of schools. For high school economics teachers, there is a growing number of podcasts targeted for instruction on economics. While the podcasts can be useful resources for teachers trying to enhance students' economic thinking, they are not produced…

  5. Folding Our Way to Productivity. Active Learning Lessons. Economics International.

    ERIC Educational Resources Information Center

    Baranova, Daira; Bottomoley, Alice; Brock, John; Shappo, Natalia

    This lesson plan was developed through "Economics International," an international program to help build economic education infrastructures in the emerging market economies. It provides a lesson description; economic concepts; content standards and benchmarks; related subject areas; instructional objectives; time required for lesson…

  6. The Production, Consumption and Distribution of Economic Podcasts

    ERIC Educational Resources Information Center

    Swan, Kathy; Hofer, Mark; Swan, Gerry; Mazur, Joan

    2010-01-01

    Podcasting remains one of the hot "buzz words" in technology today--both in and out of schools. For high school economics teachers, there is a growing number of podcasts targeted for instruction on economics. While the podcasts can be useful resources for teachers trying to enhance students' economic thinking, they are not produced…

  7. Assessing the agricultural costs of climate change: Combining results from crop and economic models

    NASA Astrophysics Data System (ADS)

    Howitt, R. E.

    2016-12-01

    Any perturbation to a resource system used by humans elicits both technical and behavioral changes. For agricultural production, economic criteria and their associated models are usually good predictors of human behavior in agricultural production. Estimation of the agricultural costs of climate change requires careful downscaling of global climate models to the level of agricultural regions. Plant growth models for the dominant crops are required to accurately show the full range of trade-offs and adaptation mechanisms needed to minimize the cost of climate change. Faced with the shifts in the fundamental resource base of agriculture, human behavior can either exacerbate or offset the impact of climate change on agriculture. In addition, agriculture can be an important source of increased carbon sequestration. However the effectiveness and timing of this sequestration depends on agricultural practices and farmer behavior. Plant growth models and economic models have been shown to interact in two broad fashions. First there is the direct embedding of a parametric representation plant growth simulations in the economic model production function. A second and more general approach is to have plant growth and crop process models interact with economic models as they are simulated. The development of more general wrapper programs that transfer information between models rapidly and efficiently will encourage this approach. However, this method does introduce complications in terms of matching up disparate scales both in time and space between models. Another characteristic behavioral response of agricultural production is the distinction between the intensive margin which considers the quantity of resource, for example fertilizer, used for a given crop, and the extensive margin of adjustment that measures how farmers will adjust their crop proportions in response to climate change. Ideally economic models will measure the response to both these margins of adjustment

  8. The production economics of nursing: a discussion paper.

    PubMed

    Newbold, David

    2008-01-01

    Nursing is numerically the largest health profession providing direct care, and this, plus the imperative for effective cost control, makes their costs and impact a legitimate study focus and policy target. Production theory techniques can help nurse executives maximize outcome and minimize costs, yet little of such evidence currently exists in mainstream nursing workforce research. The balance of available evidence supports an inverse association between nurse staffing levels and adverse outcomes. However, 'adequate' staffing levels may be perceived as expensive and some providers may try to reduce them. The response, in some US and Australian states, is legislation to force hospitals to implement mandatory minimum patient-to-nurse (P/N) ratios. In this paper, existing data from Aiken et al. [2003. Education levels of hospital nurses and patient mortality. Journal of the American Medical Association 290, 1617-1623] is re-interpreted using production theory, to illustrate the possible relationship between two key workforce variables "Staff Level" and "Staff Mix", and clinical outcome, and show how this informs decision making. Consistent with other studies, this suggests that diminishing returns to each variable exist. This preliminary analysis suggests that increasing the number of graduate RNs in the workforce might be the most cost-effective way to expand the nursing workforce. However, more detailed and rigorous research is needed to estimate speciality specific cost and production functions and compute the optimal solution. This can predict the most cost-effective staff combination for a set outcome, or the set of inputs yielding best outcome for a given budget. With this, nurse executives can systematically maintain service quality or safety in the most economical way.

  9. Estimation of economic impacts of cellulosic biofuel production: a comparative analysis of three biofuel pathways: Economic impacts of biofuel production

    SciTech Connect

    Zhang, Yimin; Goldberg, Marshall; Tan, Eric; Meyer, Pimphan Aye

    2016-03-07

    The development of a cellulosic biofuel industry utilizing domestic biomass resources is expected to create opportunities for economic growth resulting from the construction and operation of new biorefineries. We applied an economic input-output model to estimate potential economic impacts, particularly gross job growth, resulting from the construction and operation of biorefineries using three different technology pathways: 1) cellulosic ethanol via biochemical conversion in Iowa, 2) renewable diesel blendstock via biological conversion in Georgia, and 3) renewable diesel and gasoline blendstock via fast pyrolysis in Mississippi. Combining direct, indirect, and induced effects, capital investment associated with the construction of a biorefinery processing 2,000 dry metric tons of biomass per day (DMT/day) could yield between 5,960 and 8,470 full-time equivalent (FTE) jobs during the construction period. Fast pyrolysis biorefineries produce the most jobs on a project level thanks to the highest capital requirement among the three pathways. Normalized for one million dollars of capital investment, the fast pyrolysis biorefineries are estimated to yield slighter more jobs (12.1 jobs) than the renewable diesel (11.8 jobs) and the cellulosic ethanol (11.6 jobs) biorefineries. While operating biorefineries is not labor-intensive, the annual operation of a 2,000 DMT/day biorefinery could support between 720 and 970 jobs when the direct, indirect, and induced effects are considered. The major factor, which results in the variations among the three pathways, is the type of biomass feedstock used for biofuels. The agriculture/forest, services, and trade industries are the primary sectors that will benefit from the ongoing operation of biorefineries.

  10. A microbial model of economic trading and comparative advantage.

    PubMed

    Enyeart, Peter J; Simpson, Zachary B; Ellington, Andrew D

    2015-01-07

    The economic theory of comparative advantage postulates that beneficial trading relationships can be arrived at by two self-interested entities producing the same goods as long as they have opposing relative efficiencies in producing those goods. The theory predicts that upon entering trade, in order to maximize consumption both entities will specialize in producing the good they can produce at higher efficiency, that the weaker entity will specialize more completely than the stronger entity, and that both will be able to consume more goods as a result of trade than either would be able to alone. We extend this theory to the realm of unicellular organisms by developing mathematical models of genetic circuits that allow trading of a common good (specifically, signaling molecules) required for growth in bacteria in order to demonstrate comparative advantage interactions. In Conception 1, the experimenter controls production rates via exogenous inducers, allowing exploration of the parameter space of specialization. In Conception 2, the circuits self-regulate via feedback mechanisms. Our models indicate that these genetic circuits can demonstrate comparative advantage, and that cooperation in such a manner is particularly favored under stringent external conditions and when the cost of production is not overly high. Further work could involve implementing the models in living bacteria and searching for naturally occurring cooperative relationships between bacteria that conform to the principles of comparative advantage.

  11. Barriers to knowledge production, knowledge translation, and urban health policy change: ideological, economic, and political considerations.

    PubMed

    Muntaner, Carles; Chung, Haejoo; Murphy, Kelly; Ng, Edwin

    2012-12-01

    In this paper, we consider social forces that affect the processes of both knowledge production and knowledge translation in relation to urban health research. First, we briefly review our conceptual model, derived from a social-conflict framework, to outline how unequal power relations and health inequalities are causally linked. Second, we critically discuss ideological, political, and economic barriers that exist within academia that affect knowledge production related to urban health and health inequalities. Third, we broaden the scope of our analysis to examine how the ideological, political, and economic environment beyond the academy creates barriers to health equity policy making. We conclude with some key questions about the role that knowledge translation can possibly play in light of these constraints on research and policy for urban health.

  12. Techno-economic analysis of monosaccharide production via fast pyrolysis of lignocellulose.

    PubMed

    Zhang, Yanan; Brown, Tristan R; Hu, Guiping; Brown, Robert C

    2013-01-01

    The economic feasibility of a facility producing monosaccharides, hydrogen and transportation fuels via fast pyrolysis and upgrading pathway was evaluated by modeling a 2000 dry metric ton biomass/day facility using Aspen Plus®. Equipment sizing and cost were based on Aspen Economic Evaluation® software. The results indicate that monosaccharide production capacity could reach 338 metric tons/day. Co-product yields of hydrogen and gasoline were 23.4 and 141 metric tons/day, respectively. The total installed equipment and total capital costs were estimated to be $210 million and $326 million, respectively. A facility internal rate of return (IRR) of 11.4% based on market prices of $3.33/kg hydrogen, $2.92/gal gasoline and diesel, $0.64/kg monosaccharide was calculated. Sensitivity analysis demonstrates that fixed capital cost, feedstock cost, product yields, and product credits have the greatest impacts on facility IRR. Further research is needed to optimize yield of sugar via the proposed process to improve economic feasibility.

  13. Preliminary Economics for the Production of Pyrolysis Oil from Lignin in a Cellulosic Ethanol Biorefinery

    SciTech Connect

    Jones, Susanne B.; Zhu, Yunhua

    2009-04-01

    price of $1.33 for the 2012 goal case process as reported in the 2007 State of Technology Model (NREL 2008). Hence, pyrolysis oil does not appear to be an economically attractive product in this scenario. Further research regarding fast pyrolysis of raw lignin from a cellulosic plant as an end product is not recommended. Other processes, such as high-pressure liquefaction or wet gasification, and higher value products, such as gasoline and diesel from fast pyrolysis oil should be considered in future studies.

  14. A Model of the Economic Theory of Regulation for Undergraduates.

    ERIC Educational Resources Information Center

    Wilson, Brooks

    1995-01-01

    Presents a model of the economic theory of regulation and recommends its use in undergraduate economics classes. Describes the use of computer-assisted instruction to teach the theory. Maintains that the approach enables students to gain access to graphs and tables that they produce themselves. (CFR)

  15. Community Colleges and Economic Development: Models of Institutional Effectiveness.

    ERIC Educational Resources Information Center

    Katsinas, Stephen G.; Lacey, Vincent A.

    An overview is provided of the nontraditional, direct involvement of community colleges in economic development activities. While a review of the literature and a discussion of the factors leading to community colleges' participation in economic development are included, the primary focus of the monograph is on seven models of nontraditional…

  16. Development and use of an economic evaluation model to assess establishment of local centralized rural biogas plants in Greece.

    PubMed

    Georgakakis, D; Christopoulou, N; Chatziathanassiou, A; Venetis, T

    2003-01-01

    An economic evaluation model was developed in the Laboratory of Agricultural Structures (LAS) of the Agricultural University of Athens-the Modified Basic Economic Evaluation Model (MBEEM). This model is an improved version of the original Basic Economic Evaluation Model, available in LAS, and it is used to assess the cost-effectiveness of biogas production systems. Because of the parameters involved, a computer model was developed to facilitate the application of the MBEEM. The model was used in this work to determine the cost-effective size of a local centralized biogas production system fed with pig wastes.

  17. The economic aspects of artificial snow production in the perspective of climate change

    NASA Astrophysics Data System (ADS)

    Gonseth, C.

    2012-04-01

    levels that are not optimal in the sense that they do not maximize social welfare. More generally, economic analysis has the potential to explain current investment and snow production levels and to determine optimal ones. It can also predict the evolution of these levels under a warmer climate. For instance, such predictions were carried out for Switzerland as well as for other Alpine countries using a computable general equilibrium model of the world economy with a time horizon up to 2050, the GEMINI-E3 model. With all these points in mind, this presentation aims at reviewing what has been done so far on the economic aspects of artificial snow production and also at identifying avenues for future research.

  18. Economic and life cycle assessments of biomass utilization for bioenergy products

    DOE PAGES

    Liu, Weiguo; Wang, Jingxin; Richard, Tom L.; ...

    2017-05-04

    A modeling process was developed to examine the economic and environmental benefits of utilizing energy crops for biofuels and bioproducts. Three energy crops (hybrid willow, switchgrass and miscanthus) that can potentially grow on marginal agricultural land or abandoned mine land in the northeastern United States were considered in the analytical process for the production of biofuels, biopower and pellet fuel. The supply chain components for both the economic analysis and life cycle modeling processes included feedstock establishment, harvest, transportation, storage, preprocessing, conversion, distribution and final usage. Sensitivity analysis was also conducted to assess the effects of energy crop yield, transportationmore » distance, conversion rate, facility capacity and internal rate of return (IRR) on the production of bioenergy products. The required selling price (RSP) ranged from $ 7.7/GJ to $ 47.9/GJ for different bioproducts. The production of biopower had the highest RSP and pellet fuel had the lowest. The results also indicated that bioenergy production using hybrid willow demonstrated lower RSP than the two perennial grass feedstocks. Pellet production presented the lowest greenhouse gas (GHG) emissions (less than 10 kg CO2 eq per 1,000 MJ) and fossil energy consumption (less than 150 MJ per 1,000 MJ). The production of biofuel resulted in the highest GHG emissions. Sensitivity analysis indicated that IRR was the most sensitive factor to RSP and followed by conversion rate for biofuel and biopower production. As a result, conversion rate and transportation distance of feedstock presented a significant effect on environmental impacts during the production of the bioproducts.« less

  19. Processing and economic impacts of biomass delignification for ethanol production

    SciTech Connect

    Elander, R.T.; Hsu, T.

    1995-12-31

    The need for chemical pretreatment of biomass for the enzyme-catalyzed production of ethanol from lignocellulosic feedstocks has been established. Past research in the Alternative Fuels Division of the National Renewable Energy Laboratory has focused on dilute acid prehydrolysis processes as a means of hydrolyzing the hemicellulose component of biomass. Such processes provide a solid residue that is more easily hydrolyzable by cellulose enzymes, as well as a hemicellulose-sugar component that can be converted by pentose-fermenting microorganisms. This work investigates the technical and economic feasibility of including a separate biomass delignification/fractionation step, either in conjunction with dilute acid prehydrolysis or as an independent pretreatment process. These alternatives would not only solubilize the hemicellulose component of a biomass feedstock, but the lignin fraction as well. The resulting residual solids would be primarily composed of cellulose. The benefits found in converting such material to ethanol may include lower cellulose requirements, shorter bioconversion times, higher effective cellulose concentrations resulting in higher ethanol concentrations, smaller reactor volumes, and more efficient enzyme recycle options. A technoeconomic assessment indicates that improvements in these process parameters can lead to significant savings that can cover the costs of such process additions.

  20. The Changing Economic Model of Scholarly Publishing: Uncertainty, Complexity and Multi-media Serials.

    ERIC Educational Resources Information Center

    Cox, John

    1998-01-01

    Discusses scholarly publishing, comparing traditional, 80s, and present models of scholarly publishing; outlines economic factors characterizing the models: costs of production, subscription decline, numbers of articles published, editorial expenses and fees, office expenses, pressure for profit, start-up costs of new journals; and describes how…

  1. Hydro-economic Modeling: Reducing the Gap between Large Scale Simulation and Optimization Models

    NASA Astrophysics Data System (ADS)

    Forni, L.; Medellin-Azuara, J.; Purkey, D.; Joyce, B. A.; Sieber, J.; Howitt, R.

    2012-12-01

    The integration of hydrological and socio economic components into hydro-economic models has become essential for water resources policy and planning analysis. In this study we integrate the economic value of water in irrigated agricultural production using SWAP (a StateWide Agricultural Production Model for California), and WEAP (Water Evaluation and Planning System) a climate driven hydrological model. The integration of the models is performed using a step function approximation of water demand curves from SWAP, and by relating the demand tranches to the priority scheme in WEAP. In order to do so, a modified version of SWAP was developed called SWEAP that has the Planning Area delimitations of WEAP, a Maximum Entropy Model to estimate evenly sized steps (tranches) of water derived demand functions, and the translation of water tranches into crop land. In addition, a modified version of WEAP was created called ECONWEAP with minor structural changes for the incorporation of land decisions from SWEAP and series of iterations run via an external VBA script. This paper shows the validity of this integration by comparing revenues from WEAP vs. ECONWEAP as well as an assessment of the approximation of tranches. Results show a significant increase in the resulting agricultural revenues for our case study in California's Central Valley using ECONWEAP while maintaining the same hydrology and regional water flows. These results highlight the gains from allocating water based on its economic compared to priority-based water allocation systems. Furthermore, this work shows the potential of integrating optimization and simulation-based hydrologic models like ECONWEAP.ercentage difference in total agricultural revenues (EconWEAP versus WEAP).

  2. A physical and economic model of the nuclear fuel cycle

    NASA Astrophysics Data System (ADS)

    Schneider, Erich Alfred

    A model of the nuclear fuel cycle that is suitable for use in strategic planning and economic forecasting is presented. The model, to be made available as a stand-alone software package, requires only a small set of fuel cycle and reactor specific input parameters. Critical design criteria include ease of use by nonspecialists, suppression of errors to within a range dictated by unit cost uncertainties, and limitation of runtime to under one minute on a typical desktop computer. Collision probability approximations to the neutron transport equation that lead to a computationally efficient decoupling of the spatial and energy variables are presented and implemented. The energy dependent flux, governed by coupled integral equations, is treated by multigroup or continuous thermalization methods. The model's output includes a comprehensive nuclear materials flowchart that begins with ore requirements, calculates the buildup of 24 actinides as well as fission products, and concludes with spent fuel or reprocessed material composition. The costs, direct and hidden, of the fuel cycle under study are also computed. In addition to direct disposal and plutonium recycling strategies in current use, the model addresses hypothetical cycles. These include cycles chosen for minor actinide burning and for their low weapons-usable content.

  3. Evaluating the economics of biomass energy production in the Watts Bar region

    SciTech Connect

    Alexander, R.R.; English, B.C.; Bhat, M.G.; Graham, R.L.

    1993-12-31

    While the commercial potential of biofuel technology is becoming more feasible, it is not clear whether the supply of biomass feedstock will be available in competitive markets. In order to exploit the potential of biomass crops as a reliable source of biofuels, a significant commitment on the part of farmers to convert large amounts of cropland would be required. Dedicated energy crops have to compete with conventional crops which could result in significant interregional shifts in crop production. Those changes could further affect overall agricultural production, food prices, consumer spending, and government spending on farm programs. Evaluating these economic impacts provides important information for the ongoing debate. This research is a case study incorporating an existing power plant. The objective of this project is to evaluate the potential of short rotation woody crops as a fuel source in the Watts Bar facility located in eastern Tennessee. The appraisal includes estimates of environmental impacts as well as of economic feasibility. This is achieved by estimating the amounts of biomass that would be supplied at a predetermined price. By changing prices of biomass at the plant in an incremental fashion, a regional supply curve for biomass is estimated. The model incorporates current agricultural production possibilities in the region along with the proposed short rotation woody crop production activities. In order to adequately model the landscape, several variables are considered. These variables include soil type, crop production, government policy, land use conversion to crop land, and distance from the plant. Environmental issues including erosion, chemical usage, and potential leaching are also incorporated within the modeling framework; however, only estimates on erosion are available in this analysis. Output from the model provides insight on where and what types of land should shift from current land use to biomass production.

  4. A proposed tool to integrate environmental and economical assessments of products

    SciTech Connect

    Senthil, Kumaran D.; Ong, S.K.; Nee, A.Y.C.; Tan, Reginald B.H

    2003-01-01

    An attempt has been made to interpret the outcomes of a Life Cycle Assessment (LCA) in terms of environmental costs. This attempt ensures the environmental accountability of the products while LCA ensures their eco-friendly nature. Keeping this as an objective, a Life Cycle Environmental Cost Analysis (LCECA) model was developed. This new tool incorporates costing into the LCA practice. This model prescribes a life cycle environmental cost model to estimate and correlate the effects of these costs in all the life cycle stages of the product. The newly developed categories of eco-costs are: costs of effluent treatment/control/disposal, environmental management systems, eco-taxes, rehabilitation, energy and savings of recycling and reuse strategies. The mathematical model of LCECA determines quantitative expressions between the total cost of products and the various eco-costs. The eco-costs of the alternatives are compared with the computational LCECA model. This method enables the environmental as well as the economic assessment of products, which leads to cost-effective, eco-friendly design of products.

  5. JEDI: Jobs and Economic Development Impacts Model Fact Sheet

    SciTech Connect

    S. Hendrickson; S.Tegen

    2009-12-01

    The Jobs and Economic Development Impact (JEDI) models are user-friendly tools that estimate the economic impacts of constructing and operating power generation and biofuel plants at the local(usually state) level. First developed by NREL's Wind Powering America program to model wind energy jobs and impacts, JEDI has been expanded to biofuels,concentrating solar power, coal, and natural gas power plants.

  6. Computer models for economic and silvicultural decisions

    Treesearch

    Rosalie J. Ingram

    1989-01-01

    Computer systems can help simplify decisionmaking to manage forest ecosystems. We now have computer models to help make forest management decisions by predicting changes associated with a particular management action. Models also help you evaluate alternatives. To be effective, the computer models must be reliable and appropriate for your situation.

  7. External Economic Drivers and U.S. Agricultural Production Systems

    USDA-ARS?s Scientific Manuscript database

    U.S agriculture operates in a market driven economy. As with other businesses, agricultural producers respond to economic incentives and disincentives and make decisions to maximize their welfare. In this paper we examine external economic drivers that shape agricultural systems. Specifically, we c...

  8. An Educational Production Function for Principles of Economics.

    ERIC Educational Resources Information Center

    Manahan, Jerry

    1983-01-01

    Empirical evidence analyzed indicates that achievement of college students in economics is predicted by age, student ability, and quality of instruction. Their attitudes towards economics are explained by several socioeconomic variables, the students' perceptions of the quality of instruction, and the changes in the students' expected grades.…

  9. Agricultural climate impacts assessment for economic modeling and decision support

    NASA Astrophysics Data System (ADS)

    Thomson, A. M.; Izaurralde, R. C.; Beach, R.; Zhang, X.; Zhao, K.; Monier, E.

    2013-12-01

    A range of approaches can be used in the application of climate change projections to agricultural impacts assessment. Climate projections can be used directly to drive crop models, which in turn can be used to provide inputs for agricultural economic or integrated assessment models. These model applications, and the transfer of information between models, must be guided by the state of the science. But the methodology must also account for the specific needs of stakeholders and the intended use of model results beyond pure scientific inquiry, including meeting the requirements of agencies responsible for designing and assessing policies, programs, and regulations. Here we present methodology and results of two climate impacts studies that applied climate model projections from CMIP3 and from the EPA Climate Impacts and Risk Analysis (CIRA) project in a crop model (EPIC - Environmental Policy Indicator Climate) in order to generate estimates of changes in crop productivity for use in an agricultural economic model for the United States (FASOM - Forest and Agricultural Sector Optimization Model). The FASOM model is a forward-looking dynamic model of the US forest and agricultural sector used to assess market responses to changing productivity of alternative land uses. The first study, focused on climate change impacts on the UDSA crop insurance program, was designed to use available daily climate projections from the CMIP3 archive. The decision to focus on daily data for this application limited the climate model and time period selection significantly; however for the intended purpose of assessing impacts on crop insurance payments, consideration of extreme event frequency was critical for assessing periodic crop failures. In a second, coordinated impacts study designed to assess the relative difference in climate impacts under a no-mitigation policy and different future climate mitigation scenarios, the stakeholder specifically requested an assessment of a

  10. Application of risk-rated profit model functions in estimation of economic values for indigenous chicken breeding.

    PubMed

    Okeno, Tobias O; Magothe, Thomas M; Kahi, Alexander K; Peters, Kurt J

    2012-08-01

    The economic values for productive (egg number, average daily gain, live weight, and mature weight) and functional (fertility, hatchability, broodiness, survival rate, feed intake, and egg weight) traits were derived for three production systems utilizing indigenous chicken in Kenya. The production systems considered were free-range, semi-intensive, and intensive system and were evaluated based on fixed flock size and fixed feed resource production circumstances. A bio-economic model that combined potential performances, feeding strategies, optimum culling strategies, farmer's preferences and accounted for imperfect knowledge concerning risk attitude of farmers and economic dynamics was employed to derive risk-rated economic values. The economic values for all the traits were highest in free-range system under the two production circumstances and decreased with level of intensification. The economic values for egg number, average daily gain, live weight, fertility, hatchability, and survival rate were positive while those for mature weight, broodiness, egg weight, and feed intake were negative. Generally, the economic values estimated under fixed feed resource production circumstances were higher than those derived under fixed flock size. The difference between economic values estimated using simple (traditional) and risk-rated profit model functions ranged from -47.26% to +67.11% indicating that inclusion of risks in estimation of economic values is important. The results of this study suggest that improvement targeting egg number, average daily gain, live weight, fertility, hatchability, and survival rate would have a positive impact on profitability of indigenous chicken production in Kenya.

  11. Global economic consequences of selected surgical diseases: a modelling study.

    PubMed

    Alkire, Blake C; Shrime, Mark G; Dare, Anna J; Vincent, Jeffrey R; Meara, John G

    2015-04-27

    The surgical burden of disease is substantial, but little is known about the associated economic consequences. We estimate the global macroeconomic impact of the surgical burden of disease due to injury, neoplasm, digestive diseases, and maternal and neonatal disorders from two distinct economic perspectives. We obtained mortality rate estimates for each disease for the years 2000 and 2010 from the Institute of Health Metrics and Evaluation Global Burden of Disease 2010 study, and estimates of the proportion of the burden of the selected diseases that is surgical from a paper by Shrime and colleagues. We first used the value of lost output (VLO) approach, based on the WHO's Projecting the Economic Cost of Ill-Health (EPIC) model, to project annual market economy losses due to these surgical diseases during 2015-30. EPIC attempts to model how disease affects a country's projected labour force and capital stock, which in turn are related to losses in economic output, or gross domestic product (GDP). We then used the value of lost welfare (VLW) approach, which is conceptually based on the value of a statistical life and is inclusive of non-market losses, to estimate the present value of long-run welfare losses resulting from mortality and short-run welfare losses resulting from morbidity incurred during 2010. Sensitivity analyses were performed for both approaches. During 2015-30, the VLO approach projected that surgical conditions would result in losses of 1·25% of potential GDP, or $20·7 trillion (2010 US$, purchasing power parity) in the 128 countries with data available. When expressed as a proportion of potential GDP, annual GDP losses were greatest in low-income and middle-income countries, with up to a 2·5% loss in output by 2030. When total welfare losses are assessed (VLW), the present value of economic losses is estimated to be equivalent to 17% of 2010 GDP, or $14·5 trillion in the 175 countries assessed with this approach. Neoplasm and injury account

  12. Multi-basin, Multi-sector Drought Economic Impact Model in Python: Development and Applications

    NASA Astrophysics Data System (ADS)

    Gutenson, J. L.; Zhu, L.; Ernest, A. N. S.; Oubeidillah, A.; Bearden, B.; Johnson, T. G.

    2015-12-01

    Drought is one of the most economically disastrous natural hazards, one whose impacts are exacerbated by the lack of abrupt onset and offset that define tornados and hurricanes. In the United States, about 30 billion dollars losses is caused by drought in 2012, resulting in widespread economic impacts for societies, industries, agriculture, and recreation. And in California, the drought cost statewide economic losses about 2.2 billion, with a total loss of 17,100 seasonal and part-time jobs. Driven by a variety of factors including climate change, population growth, increased water demands, alteration to land cover, drought occurs widely all over the world. Drought economic consequence assessment tool are greatly needed to allow decision makers and stakeholders to anticipate and manage effectively. In this study, current drought economic impact modeling methods were reviewed. Most of these models only deal with the impact in the agricultural sector with a focus on a single basin; few of these models analyze long term impact. However, drought impacts are rarely restricted to basin boundaries, and cascading economic impacts are likely to be significant. A holistic approach to multi-basin, multi-sector drought economic impact assessment is needed.In this work, we developed a new model for drought economic impact assessment, Drought Economic Impact Model in Python (PyDEM). This model classified all business establishments into thirteen categories based on NAICS, and using a continuous dynamic social accounting matrix approach, coupled with calculation of the indirect consequences for the local and regional economies and the various resilience. In addition, Environmental Policy Integrated Climate model was combined for analyzing drought caused soil erosion together with agriculture production, and then the long term impacts of drought were achieved. A visible output of this model was presented in GIS. In this presentation, Choctawhatchee-Pea-Yellow River Basins, Alabama

  13. Modelling the interaction between flooding events and economic growth

    NASA Astrophysics Data System (ADS)

    Grames, J.; Prskawetz, A.; Grass, D.; Blöschl, G.

    2015-06-01

    Socio-hydrology describes the interaction between the socio-economy and water. Recent models analyze the interplay of community risk-coping culture, flooding damage and economic growth (Di Baldassarre et al., 2013; Viglione et al., 2014). These models descriptively explain the feedbacks between socio-economic development and natural disasters like floods. Contrary to these descriptive models, our approach develops an optimization model, where the intertemporal decision of an economic agent interacts with the hydrological system. In order to build this first economic growth model describing the interaction between the consumption and investment decisions of an economic agent and the occurrence of flooding events, we transform an existing descriptive stochastic model into an optimal deterministic model. The intermediate step is to formulate and simulate a descriptive deterministic model. We develop a periodic water function to approximate the former discrete stochastic time series of rainfall events. Due to the non-autonomous exogenous periodic rainfall function the long-term path of consumption and investment will be periodic.

  14. Economic analysis of open space box model utilization in spacecraft

    NASA Astrophysics Data System (ADS)

    Mohammad, Atif F.; Straub, Jeremy

    2015-05-01

    It is a known fact that the amount of data about space that is stored is getting larger on an everyday basis. However, the utilization of Big Data and related tools to perform ETL (Extract, Transform and Load) applications will soon be pervasive in the space sciences. We have entered in a crucial time where using Big Data can be the difference (for terrestrial applications) between organizations underperforming and outperforming their peers. The same is true for NASA and other space agencies, as well as for individual missions and the highly-competitive process of mission data analysis and publication. In most industries, conventional opponents and new candidates alike will influence data-driven approaches to revolutionize and capture the value of Big Data archives. The Open Space Box Model is poised to take the proverbial "giant leap", as it provides autonomic data processing and communications for spacecraft. We can find economic value generated from such use of data processing in our earthly organizations in every sector, such as healthcare, retail. We also can easily find retailers, performing research on Big Data, by utilizing sensors driven embedded data in products within their stores and warehouses to determine how these products are actually used in the real world.

  15. Stochastic modeling of economic injury levels with respect to yearly trends in price commodity.

    PubMed

    Damos, Petros

    2014-05-01

    The economic injury level (EIL) concept integrates economics and biology and uses chemical applications in crop protection only when economic loss by pests is anticipated. The EIL is defined by five primary variables: the cost of management tactic per production unit, the price of commodity, the injury units per pest, the damage per unit injury, and the proportionate reduction of injury averted by the application of a tactic. The above variables are related according to the formula EIL = C/VIDK. The observable dynamic alteration of the EIL due to its different parameters is a major characteristic of its concept. In this study, the yearly effect of the economic variables is assessed, and in particular the influence of the parameter commodity value on the shape of the EIL function. In addition, to predict the effects of the economic variables on the EIL level, yearly commodity values were incorporated in the EIL formula and the generated outcomes were further modelled with stochastic linear autoregressive models having different orders. According to the AR(1) model, forecasts for the five-year period of 2010-2015 ranged from 2.33 to 2.41 specimens per sampling unit. These values represent a threshold that is in reasonable limits to justify future control actions. Management actions as related to productivity and price commodity significantly affect costs of crop production and thus define the adoption of IPM and sustainable crop production systems at local and international levels.

  16. Stochastic Modeling of Economic Injury Levels with Respect to Yearly Trends in Price Commodity

    PubMed Central

    2014-01-01

    The economic injury level (EIL) concept integrates economics and biology and uses chemical applications in crop protection only when economic loss by pests is anticipated. The EIL is defined by five primary variables: the cost of management tactic per production unit, the price of commodity, the injury units per pest, the damage per unit injury, and the proportionate reduction of injury averted by the application of a tactic. The above variables are related according to the formula EIL = C/VIDK. The observable dynamic alteration of the EIL due to its different parameters is a major characteristic of its concept. In this study, the yearly effect of the economic variables is assessed, and in particular the influence of the parameter commodity value on the shape of the EIL function. In addition, to predict the effects of the economic variables on the EIL level, yearly commodity values were incorporated in the EIL formula and the generated outcomes were further modelled with stochastic linear autoregressive models having different orders. According to the AR(1) model, forecasts for the five-year period of 2010–2015 ranged from 2.33 to 2.41 specimens per sampling unit. These values represent a threshold that is in reasonable limits to justify future control actions. Management actions as related to productivity and price commodity significantly affect costs of crop production and thus define the adoption of IPM and sustainable crop production systems at local and international levels. PMID:25373206

  17. Integrated Economic Modeling of Water Supply-Quality Tradeoffs: An Application to the Central Valley, California

    NASA Astrophysics Data System (ADS)

    Bair, L.; MacEwan, D.

    2015-12-01

    Sustainable water management in the San Joaquin Valley, California involves the complex interaction of agricultural, municipal and industrial, and environmental water use. California's Sustainable Groundwater Management Act (SGMA) of 2014 requires groundwater basins historically in a state of overdraft to bring the basin into a sustainable balance over the next 20 years. In addition to limiting groundwater availability, implementation of the SGMA has implications for surface and groundwater quality. Availability of groundwater influences agricultural production decisions, resulting in variation in agricultural runoff and changes to surface and groundwater quality. Changes in water quality have economic impacts on agricultural production and urban water use. These impacts range from reductions in crop productivity to costs of alternative water supplies to amend declining water quality. We model the impact of agricultural and urban groundwater availability on surface water quality within the San Joaquin and Kings River watersheds in the Central Valley, downriver to the Mendota Pool by linking SWAT (Soil and Water Assessment Tool), an integrated water supply-quality model, with SWAP (Statewide Agricultural Production Model), a regional agricultural economics model. The integrated model specifies the relationship between changes in groundwater availability, groundwater elevation, agricultural production, and surface water quality. We link the SWAT-SWAP model output to urban and agricultural economic loss calculations that are a function of water quality. Model results demonstrate the economic tradeoffs between groundwater availability and water quality. The results of the integrated economic water supply-quality model are applicable to other regions in California and elsewhere that contain complex water supply-quality interactions.

  18. Spatial Modeling of Indian Agriculture, Economic Activity and Population under Climate Change

    NASA Astrophysics Data System (ADS)

    McCord, G. C.

    2010-12-01

    We present a spatial model of economic activity and human population built on physical geography that takes particular account of its effects through agricultural productivity and transport costs for trade. A major component of this work is an agricultural model, driven in part by high-resolution climate data and model output. We put forward India as the initial region for this modeling work; India is a relatively data-rich country, it exhibits significant within-country spatial and temporal variation in agricultural productivity, urbanization rates, and population growth rates, and the climate dynamics of the monsoon are well-studied and expected to change on decadal time scales. Agricultural productivity is modeled as a function of soil, climate, and technology variables. Farmers locate optimally given varying geography and transport costs; in turn, food availability defines urbanization rates and economic activity in non-agricultural sectors. This “social system” integrated assessment model is a step towards a valuable policy tool, but requires a significant mobilization of data and a grid-cell-level system of equations to describe the underlying dynamics of the model. We test against past trends of social-natural system progression in demography, human location, income, food production, etc., and argue that the model could be used to assess future trends under varying climate change scenarios, and eventually serve to model feedbacks through effects on migration, population growth rates, or economic activity.

  19. NEUROBIOLOGY OF ECONOMIC CHOICE: A GOOD-BASED MODEL

    PubMed Central

    Padoa-Schioppa, Camillo

    2012-01-01

    Traditionally the object of economic theory and experimental psychology, economic choice recently became a lively research focus in systems neuroscience. Here I summarize the emerging results and I propose a unifying model of how economic choice might function at the neural level. Economic choice entails comparing options that vary on multiple dimensions. Hence, while choosing, individuals integrate different determinants into a subjective value; decisions are then made by comparing values. According to the good-based model, the values of different goods are computed independently of one another, which implies transitivity. Values are not learned as such, but rather computed at the time of choice. Most importantly, values are compared within the space of goods, independent of the sensori-motor contingencies of choice. Evidence from neurophysiology, imaging and lesion studies indicates that abstract representations of value exist in the orbitofrontal and ventromedial prefrontal cortices. The computation and comparison of values may thus take place within these regions. PMID:21456961

  20. Full employment and competition in the Aspen economic model: implications for modeling acts of terrorism.

    SciTech Connect

    Sprigg, James A.; Ehlen, Mark Andrew

    2004-11-01

    Acts of terrorism could have a range of broad impacts on an economy, including changes in consumer (or demand) confidence and the ability of productive sectors to respond to changes. As a first step toward a model of terrorism-based impacts, we develop here a model of production and employment that characterizes dynamics in ways useful toward understanding how terrorism-based shocks could propagate through the economy; subsequent models will introduce the role of savings and investment into the economy. We use Aspen, a powerful economic modeling tool developed at Sandia, to demonstrate for validation purposes that a single-firm economy converges to the known monopoly equilibrium price, output, and employment levels, while multiple-firm economies converge toward the competitive equilibria typified by lower prices and higher output and employment. However, we find that competition also leads to churn by consumers seeking lower prices, making it difficult for firms to optimize with respect to wages, prices, and employment levels. Thus, competitive firms generate market ''noise'' in the steady state as they search for prices and employment levels that will maximize profits. In the context of this model, not only could terrorism depress overall consumer confidence and economic activity but terrorist acts could also cause normal short-run dynamics to be misinterpreted by consumers as a faltering economy.

  1. A fuzzy cost-benefit function to select economical products for processing in a closed-loop supply chain

    NASA Astrophysics Data System (ADS)

    Pochampally, Kishore K.; Gupta, Surendra M.; Cullinane, Thomas P.

    2004-02-01

    The cost-benefit analysis of data associated with re-processing of used products often involves the uncertainty feature of cash-flow modeling. The data is not objective because of uncertainties in supply, quality and disassembly times of used products. Hence, decision-makers must rely on "fuzzy" data for analysis. The same parties that are involved in the forward supply chain often carry out the collection and re-processing of used products. It is therefore important that the cost-benefit analysis takes the data of both new products and used products into account. In this paper, a fuzzy cost-benefit function is proposed that is used to perform a multi-criteria economic analysis to select the most economical products to process in a closed-loop supply chain. Application of the function is detailed through an illustrative example.

  2. Economic Modeling and Analysis of Educational Vouchers

    ERIC Educational Resources Information Center

    Epple, Dennis; Romano, Richard

    2012-01-01

    The analysis of educational vouchers has evolved from market-based analogies to models that incorporate distinctive features of the educational environment. These distinctive features include peer effects, scope for private school pricing and admissions based on student characteristics, the linkage of household residential and school choices in…

  3. Model Learner Outcomes for Home Economics Education.

    ERIC Educational Resources Information Center

    Rogers, Cheryl, Ed.; And Others

    Chapter 1 of this document contains sets of statements adopted by either the Minnesota State Board of Education or the Minnesota State Legislature. They represent the hierarchy used by Department of Education staff as they develop model learner outcomes for each subject area. Contents include learner values, education system values, philosophy for…

  4. Economic Modeling and Analysis of Educational Vouchers

    ERIC Educational Resources Information Center

    Epple, Dennis; Romano, Richard

    2012-01-01

    The analysis of educational vouchers has evolved from market-based analogies to models that incorporate distinctive features of the educational environment. These distinctive features include peer effects, scope for private school pricing and admissions based on student characteristics, the linkage of household residential and school choices in…

  5. Model Learner Outcomes for Home Economics Education.

    ERIC Educational Resources Information Center

    Rogers, Cheryl, Ed.; And Others

    Chapter 1 of this document contains sets of statements adopted by either the Minnesota State Board of Education or the Minnesota State Legislature. They represent the hierarchy used by Department of Education staff as they develop model learner outcomes for each subject area. Contents include learner values, education system values, philosophy for…

  6. Army Manpower Cost System (AMCOS) Economic and Budget Cost Models.

    DTIC Science & Technology

    1985-06-30

    STANDARDS - 963 - A ZRDMServices0opaiy in (o FINAL REPORT Tm ARMY MANPOWER COST SYSTEM4 (ANCOS) ECONOMIC AND BUDGET I COST MODELS CONTRACT NO. N00014...34-- . . .+r7’’ .•. .’. FINAL REPORT ARMY MANPOWER COST SYSTEM (AMCOS) ECONOMIC AND BUDGET COST MODELS CONTRACT NO. N00014-84-C-0712 - JUNE 30, 1985...lack, the Army Research Institute is supporting the development of a family of models in the Army Manpower Cost System -AMCOS). .. ": The work reported

  7. Economic analysis of model validation for a challenge problem

    DOE PAGES

    Paez, Paul J.; Paez, Thomas L.; Hasselman, Timothy K.

    2016-02-19

    It is now commonplace for engineers to build mathematical models of the systems they are designing, building, or testing. And, it is nearly universally accepted that phenomenological models of physical systems must be validated prior to use for prediction in consequential scenarios. Yet, there are certain situations in which testing only or no testing and no modeling may be economically viable alternatives to modeling and its associated testing. This paper develops an economic framework within which benefit–cost can be evaluated for modeling and model validation relative to other options. The development is presented in terms of a challenge problem. Asmore » a result, we provide a numerical example that quantifies when modeling, calibration, and validation yield higher benefit–cost than a testing only or no modeling and no testing option.« less

  8. Economic analysis of model validation for a challenge problem

    SciTech Connect

    Paez, Paul J.; Paez, Thomas L.; Hasselman, Timothy K.

    2016-02-19

    It is now commonplace for engineers to build mathematical models of the systems they are designing, building, or testing. And, it is nearly universally accepted that phenomenological models of physical systems must be validated prior to use for prediction in consequential scenarios. Yet, there are certain situations in which testing only or no testing and no modeling may be economically viable alternatives to modeling and its associated testing. This paper develops an economic framework within which benefit–cost can be evaluated for modeling and model validation relative to other options. The development is presented in terms of a challenge problem. As a result, we provide a numerical example that quantifies when modeling, calibration, and validation yield higher benefit–cost than a testing only or no modeling and no testing option.

  9. Economics.

    PubMed

    Palley, Paul D; Parcero, Miriam E

    2016-10-01

    A review of literature in the calendar year 2015 dedicated to environmental policies and sustainable development, and economic policies. This review is divided into these sections: sustainable development, irrigation, ecosystems and water management, climate change and disaster risk management, economic growth, water supply policies, water consumption, water price regulation, and water price valuation.

  10. Citrus production systems to survive greening: economic thresholds.

    USDA-ARS?s Scientific Manuscript database

    Advanced Production Systems (APS) and Open Hydroponic Systems (OHS) are proposed strategies for citrus production that could increase early production and sustain production at higher levels through perhaps the first 15 years of grove life. Higher tree densities, automated irrigation, and intensive ...

  11. Are predictive biomarkers of toxicity worth having? An economic model.

    PubMed

    Jones, Byron; Smith, Dennis A; Schmid, Esther F

    2012-01-01

    In this paper we model the cost-benefit of excluding populations at risk through predictive toxicity biomarkers and diagnostics. False positives/ negatives inherent in predictive markers and the frequency and nature of adverse events determine whether biomarkers are beneficial and economically viable. We present a model that takes these and other factors into account using data largely in line with real world cases.

  12. Activity-Based Costing Model for Assessing Economic Performance.

    ERIC Educational Resources Information Center

    DeHayes, Daniel W.; Lovrinic, Joseph G.

    1994-01-01

    An economic model for evaluating the cost performance of academic and administrative programs in higher education is described. Examples from its application at Indiana University-Purdue University Indianapolis are used to illustrate how the model has been used to control costs and reengineer processes. (Author/MSE)

  13. Economic Modeling as a Component of Academic Strategic Planning.

    ERIC Educational Resources Information Center

    MacKinnon, Joyce; Sothmann, Mark; Johnson, James

    2001-01-01

    Computer-based economic modeling was used to enable a school of allied health to define outcomes, identify associated costs, develop cost and revenue models, and create a financial planning system. As a strategic planning tool, it assisted realistic budgeting and improved efficiency and effectiveness. (Contains 18 references.) (SK)

  14. The Open Flip--A Digital Economic Model for Education

    ERIC Educational Resources Information Center

    Weller, Martin

    2016-01-01

    The advent of the internet and digital technologies has given rise to a number of new economic models. These have often been applied to education, but either through faults in the initial models or differences in the characteristics of the education sector, they have not proven to be widely applicable. The use of digital, network technologies…

  15. Activity-Based Costing Model for Assessing Economic Performance.

    ERIC Educational Resources Information Center

    DeHayes, Daniel W.; Lovrinic, Joseph G.

    1994-01-01

    An economic model for evaluating the cost performance of academic and administrative programs in higher education is described. Examples from its application at Indiana University-Purdue University Indianapolis are used to illustrate how the model has been used to control costs and reengineer processes. (Author/MSE)

  16. An economical canopy model for use in urban climatology

    NASA Astrophysics Data System (ADS)

    Terjung, W. H.; O'Rourke, P. A.

    1980-12-01

    A multi-layered canopy leaf energy budget model (CANOPY) has been developed for the purpose of systematically examining the building-vegetation cause and effect structure in urban landscapes. At great computer savings, this simple, parametric model compared favorably with a much more complex canopy model (SPAM). The economic operation of this model makes it possible to investigate the spatial diversity of canopy budget characteristics on a microclimatic, geographical scale.

  17. Selection of Temporal Lags When Modeling Economic and Financial Processes.

    PubMed

    Matilla-Garcia, Mariano; Ojeda, Rina B; Marin, Manuel Ruiz

    2016-10-01

    This paper suggests new nonparametric statistical tools and procedures for modeling linear and nonlinear univariate economic and financial processes. In particular, the tools presented help in selecting relevant lags in the model description of a general linear or nonlinear time series; that is, nonlinear models are not a restriction. The tests seem to be robust to the selection of free parameters. We also show that the test can be used as a diagnostic tool for well-defined models.

  18. The global impact of non-communicable diseases on macro-economic productivity: a systematic review.

    PubMed

    Chaker, Layal; Falla, Abby; van der Lee, Sven J; Muka, Taulant; Imo, David; Jaspers, Loes; Colpani, Veronica; Mendis, Shanthi; Chowdhury, Rajiv; Bramer, Wichor M; Pazoki, Raha; Franco, Oscar H

    2015-05-01

    Non-communicable diseases (NCDs) have large economic impact at multiple levels. To systematically review the literature investigating the economic impact of NCDs [including coronary heart disease (CHD), stroke, type 2 diabetes mellitus (DM), cancer (lung, colon, cervical and breast), chronic obstructive pulmonary disease (COPD) and chronic kidney disease (CKD)] on macro-economic productivity. Systematic search, up to November 6th 2014, of medical databases (Medline, Embase and Google Scholar) without language restrictions. To identify additional publications, we searched the reference lists of retrieved studies and contacted authors in the field. Randomized controlled trials, cohort, case-control, cross-sectional, ecological studies and modelling studies carried out in adults (>18 years old) were included. Two independent reviewers performed all abstract and full text selection. Disagreements were resolved through consensus or consulting a third reviewer. Two independent reviewers extracted data using a predesigned data collection form. Main outcome measure was the impact of the selected NCDs on productivity, measured in DALYs, productivity costs, and labor market participation, including unemployment, return to work and sick leave. From 4542 references, 126 studies met the inclusion criteria, many of which focused on the impact of more than one NCD on productivity. Breast cancer was the most common (n = 45), followed by stroke (n = 31), COPD (n = 24), colon cancer (n = 24), DM (n = 22), lung cancer (n = 16), CVD (n = 15), cervical cancer (n = 7) and CKD (n = 2). Four studies were from the WHO African Region, 52 from the European Region, 53 from the Region of the Americas and 16 from the Western Pacific Region, one from the Eastern Mediterranean Region and none from South East Asia. We found large regional differences in DALYs attributable to NCDs but especially for cervical and lung cancer. Productivity losses in the USA ranged from 88 million

  19. User Guide for the International Jobs and Economic Development Impacts Model

    SciTech Connect

    Keyser, David; Flores-Espino, Francisco; Uriarte, Caroline; Cox, Sadie

    2016-09-01

    The International Jobs and Economic Development Impacts (I-JEDI) model is a freely available economic model that estimates gross economic impacts from wind, solar, and geothermal energy projects for several different countries. Building on the original JEDI model, which was developed for the United States, I-JEDI was developed under the USAID Enhancing Capacity for Low Emission Development Strategies (EC-LEDS) program to support countries in assessing economic impacts of LEDS actions in the energy sector. I-JEDI estimates economic impacts by characterizing the construction and operation of energy projects in terms of expenditures and the portion of these expenditures made within the country of analysis. These data are then used in a country-specific input-output (I-O) model to estimate employment, earnings, gross domestic product (GDP), and gross output impacts. Total economic impacts are presented as well as impacts by industry. This user guide presents general information about how to use I-JEDI and interpret results as well as detailed information about methodology and model limitations.

  20. An economic model of haemophilia in Mexico.

    PubMed

    Martínez-Murillo, C; Quintana, S; Ambriz, R; Benitez, H; Berges, A; Collazo, J; Esparza, A; Pompa, T; Taboada, C; Zavala, S; Larochelle, M R; Bentkover, J D

    2004-01-01

    A model was developed to assess the lifetime costs and outcomes associated with haemophilia in Mexico. A retrospective chart review of 182 type A haemophiliacs was conducted for patients aged 0-34 years receiving one of three treatments: (i) cryoprecipitate at clinic; (ii) concentrate at home; or (iii) concentrate at clinic. Patients treated at home experienced 30% less joint damage, used 13-54% less factor VIII, had four times fewer clinic visits, and utilized half as many hospital days than those treated at a clinic. For cryoprecipitate at clinic patients, the annual incidence rates of HCV and HIV were calculated to be 3.6% and 1.4% respectively. The life expectancy for patients receiving cryoprecipitate and those receiving concentrate was estimated to be 49 years and 69 years respectively, with 58% of cryoprecipitate patients predicted to die of AIDS before age 69. Across the lifespan, the average annual cost of care was US$11,677 (MN$110,464) for cryoprecipitate at clinic patients, US$10,104 (M$95,580) for concentrate at home patients and US$18,819 (MN$178,027) for concentrate at clinic patients. Using a 5% discount rate, the incremental lifetime cost per year of life added for treatment with concentrate at home compared with cryoprecipitate at a clinic was US$738 (MN$6981). Rank order stability analysis demonstrated that the model was most sensitive to the cost of fVIII. These results indicate that treatment with concentrate at home compared with cryoprecipitate at a clinic substantially improves clinical outcomes at reduced annual cost levels.

  1. Making HEA an Engine of Economic Productivity and Worker Prosperity

    ERIC Educational Resources Information Center

    Center for Law and Social Policy CLASP, 2005

    2005-01-01

    The Higher Education Act (HEA) can be a key part of the solution to the coming "skills gap" resulting from the lack of skilled workers with postsecondary education entering the workforce. HEA should be modernized to support economic development, meet the needs of businesses and workers, and assist the growing number of "nontraditional"…

  2. Land Resources for Crop Production. Agricultural Economic Report Number 572.

    ERIC Educational Resources Information Center

    Hexem, Roger; Krupa, Kenneth S.

    About 35 million acres not being cultivated have high potential for crop use and 117 million more have medium potential, according to the 1982 National Resources Inventory (NRI) conducted by the U.S. Department of Agriculture. USDA committees evaluated the economic potential for converting land based on physical characteristics of the soil; size…

  3. Using the Global Forest Products Model (GFPM version 2012)

    Treesearch

    Joseph Buongiorno; Shushuai Zhu

    2012-01-01

    The purpose of this manual is to enable users of the Global Forest Products Model to: • Install and run the GFPM software • Understand the input data • Change the input data to explore different scenarios • Interpret the output The GFPM is an economic model of global production, consumption and trade of forest products (Buongiorno et al. 2003). The GFPM2012 has data...

  4. Process economics of renewable biorefineries: butanol and ethanol production in integrated bioprocesses from lignocellulosics and other industrial by-products

    USDA-ARS?s Scientific Manuscript database

    This chapter provides process economic details on production of butanol from lignocellulosic biomass and glycerol in integrated bioreactors where numerous unit operations are combined. In order to compare various processes, economic evaluations were performed using SuperPro Designer Software (versio...

  5. Risk Modelling of Agricultural Products

    NASA Astrophysics Data System (ADS)

    Nugrahani, E. H.

    2017-03-01

    In the real world market, agricultural commodity are imposed with fluctuating prices. This means that the price of agricultural products are relatively volatile, which means that agricultural business is a quite risky business for farmers. This paper presents some mathematical models to model such risks in the form of its volatility, based on certain assumptions. The proposed models are time varying volatility model, as well as time varying volatility with mean reversion and with seasonal mean equation models. Implementation on empirical data show that agricultural products are indeed risky.

  6. Energy efficiency, low-carbon energy production, and economic growth in CIS countries

    NASA Astrophysics Data System (ADS)

    Vazim, A.; Kochetkova, O.; Azimzhamov, I.; Shvagrukova, E.; Dmitrieva, N.

    2016-09-01

    The paper studies the peculiarities of energy efficiency increase in national economy and decrease of carbon dioxide emission for CIS countries. The conditions that allow achieving parameters of sustainable development are determined according to indexes of GDP energy intensity and carbon intensity. Focusing on the indexes of GDP energy intensity and carbon intensity dynamics as well as on carbon intensity of energy production, a real movement towards implementation of program conditions presented by international organizations is analyzed, namely, economic conversion to the model of sustainable development. The examples demonstrate both the presence of significant differences between 12 countries and the lack of fatality in these differences. At determining dependencies linear models are preferred to non-linear ones, with the explanation of reasons in each particular case. Attention to success of these countries may help to understand the advantages of conversion to the model of sustainable development and also it helps to decrease demands in terms of costs for this conversion.

  7. Economic analysis of Royalactin production under uncertainty: Evaluating the effect of parameter optimization.

    PubMed

    Torres-Acosta, Mario A; Aguilar-Yañez, Jose M; Rito-Palomares, Marco; Titchener-Hooker, Nigel J

    2015-01-01

    Royalactin is a protein with several different potential uses in humans. Research, in insects and in mammalian cells, has shown that it can accelerate cell division and prevent apoptosis. The method of action is through the use of the epidermal growth factor receptor, which is present in humans. Potential use in humans could be to lower cholesterolemic levels in blood, and to elicit similar effects to those seen in bees, e.g., increased lifespan. Mass production of Royalactin has not been accomplished, though a recent article presented a Pichia pastoris fermentation and recovery by aqueous two-phase systems at laboratory scale as a possible basis for production. Economic modelling is a useful tool with which compare possible outcomes for the production of such a molecule and in particular, to locate areas where additional research is needed and optimization may be required. This study uses the BioSolve software to perform an economic analysis on the scale-up of the putative process for Royalactin. The key parameters affecting the cost of production were located via a sensitivity analysis and then evaluated by Monte Carlo analysis. Results show that if titer is not optimized the strategy to maintain a low cost of goods is process oriented. After optimization of this parameter the strategy changes to a product-oriented and the target output becomes the critical parameter determining the cost of goods. This study serves to provide a framework for the evaluation of strategies for future production of Royalactin, by analyzing the factors that influence its cost of manufacture. © 2015 The Authors Biotechnology Progress published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers.

  8. Economics.

    ERIC Educational Resources Information Center

    James, L. D.

    1978-01-01

    Presents a literature review of the economic aspects of water pollution control covering publications of 1976-77. This review also includes the policy issues of water management. A list of 77 references is presented. (HM)

  9. Economics.

    ERIC Educational Resources Information Center

    James, L. D.

    1978-01-01

    Presents a literature review of the economic aspects of water pollution control covering publications of 1976-77. This review also includes the policy issues of water management. A list of 77 references is presented. (HM)

  10. Enhancing economic competiveness of dish Stirling technology through production volume and localization: Case study for Morocco

    NASA Astrophysics Data System (ADS)

    Larchet, Kevin; Guédez, Rafael; Topel, Monika; Gustavsson, Lars; Machirant, Andrew; Hedlund, Maria-Lina; Laumert, Björn

    2017-06-01

    The present study quantifies the reduction in the levelized cost of electricity (LCoE) and capital expenditure (CAPEX) of a dish Stirling power plant (DSPP) through an increase in localization and unit production volume. Furthermore, the localization value of the plant is examined to determine how much investment is brought into the local economy. Ouarzazate, Morocco, was chosen as the location of the study due to the country's favorable regulatory framework with regards to solar power technologies and its established industry in the concentrating solar power (CSP) field. A detailed techno-economic model of a DSPP was developed using KTH's in-house modelling tool DYESOPT, which allows power plant evaluation by means of technical and economic performance indicators. Results on the basis of LCoE and CAPEX were compared between two different cases of production volume, examining both a minimum and maximum level of localization. Thereafter, the DSPP LCoE and localization value were compared against competing solar technologies to evaluate its competitiveness. In addition, a sensitivity analysis was conducted around key design parameters. The study confirms that the LCoE of a DSPP can be reduced to values similar to solar photovoltaic (PV) and lower than other CSP technologies. Furthermore, the investment in the local economy is far greater when compared to PV and of the same magnitude to other CSP technologies. The competiveness of a DSPP has the potential to increase further when coupled with thermal energy storage (TES), which is currently under development.

  11. Modelling the role of forests on water provision services: a hydro-economic valuation approach

    NASA Astrophysics Data System (ADS)

    Beguería, S.; Campos, P.

    2015-12-01

    Hydro-economic models that allow integrating the ecological, hydrological, infrastructure, economic and social aspects into a coherent, scientifically- informed framework constitute preferred tools for supporting decision making in the context of integrated water resources management. We present a case study of water regulation and provision services of forests in the Andalusia region of Spain. Our model computes the physical water flows and conducts an economic environmental income and asset valuation of forest surface and underground water yield. Based on available hydrologic and economic data, we develop a comprehensive water account for all the forest lands at the regional scale. This forest water environmental valuation is integrated within a much larger project aiming at providing a robust and easily replicable accounting tool to evaluate yearly the total income and capital of forests, encompassing all measurable sources of private and public incomes (timber and cork production, auto-consumption, recreational activities, biodiversity conservation, carbon sequestration, water production, etc.). We also force our simulation with future socio-economic scenarios to quantify the physical and economic efects of expected trends or simulated public and private policies on future water resources. Only a comprehensive integrated tool may serve as a basis for the development of integrated policies, such as those internationally agreed and recommended for the management of water resources.

  12. Using Economic Impact Models as an Educational Tool in Community Economic Development Programming: Lessons from Pennsylvania and Wisconsin.

    ERIC Educational Resources Information Center

    Shields, Martin; Deller, Steven C.

    2003-01-01

    Outlines an educational process designed to help provide communities with economic, social, and political information using community economic impact modeling. Describes the process of community meetings using economic impact, community demographics, and fiscal impact modules and the local preconditions that help make the process successful. (SK)

  13. Hierarchical economic potential approach for techno-economic evaluation of bioethanol production from palm empty fruit bunches.

    PubMed

    Do, Truong Xuan; Lim, Young-Il; Jang, Sungsoo; Chung, Hwa-Jee

    2015-01-01

    A hierarchical four-level approach to determine economic potential (4-level EP) is proposed for preliminary techno-economic analysis of new processes. The 4-level EP includes input/output structure, process flow structure, heat integration (HI), and economic feasibility. Two case studies on a 30.2 t/d (or 12.7 million l/yr) bioethanol plant with and without jet fuel production from palm empty fruit bunches (EFB) were investigated by applying the 4-level EP. The plant flowsheet was established based on experiments in a 0.1t/d pilot plant, including sequential dilute acid and alkali pretreatment, and separate hydrolysis and fermentation (SHF). EP approached a more reliable value through the hierarchical 4-level EP. The heating energy was reduced considerably by HI. The product value was estimated at $0.8-$1.3/kg of equivalent bioethanol. It was suggested through sensitivity analysis that a large plant size, enhanced production yields, and capital cost reduction were necessary for the lignocellulosic bioethanol production to be profitable. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Microalgal production--a close look at the economics.

    PubMed

    Norsker, Niels-Henrik; Barbosa, Maria J; Vermuë, Marian H; Wijffels, René H

    2011-01-01

    Worldwide, microalgal biofuel production is being investigated. It is strongly debated which type of production technology is the most adequate. Microalgal biomass production costs were calculated for 3 different micro algal production systems operating at commercial scale today: open ponds, horizontal tubular photobioreactors and flat panel photobioreactors. For the 3 systems, resulting biomass production costs including dewatering, were 4.95, 4.15 and 5.96 € per kg, respectively. The important cost factors are irradiation conditions, mixing, photosynthetic efficiency of systems, medium- and carbon dioxide costs. Optimizing production with respect to these factors, a price of € 0.68 per kg resulted. At this cost level microalgae become a promising feedstock for biodiesel and bulk chemicals. Photobioreactors may become attractive for microalgal biofuel production. Copyright © 2010 Elsevier Inc. All rights reserved.

  15. Techno-economic analysis of biofuel production considering logistic configurations.

    PubMed

    Li, Qi; Hu, Guiping

    2016-04-01

    In the study, a techno-economic analysis method considering logistic configurations is proposed. The economic feasibility of a low temperature biomass gasification pathway and an integrated pathway with fast pyrolysis and bio-oil gasification are evaluated and compared with the proposed method in Iowa. The results show that both pathways are profitable, biomass gasification pathway could achieve an Internal Rate of Return (IRR) of 10.00% by building a single biorefinery and integrated bio-oil gasification pathway could achieve an IRR of 3.32% by applying decentralized supply chain structure. A Monte-Carlo simulation considering interactions among parameters is also proposed and conducted, which indicates that both pathways are at high risk currently. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. The projected public health and economic impact of vitamin D fortified dairy products for fracture prevention in France.

    PubMed

    Hiligsmann, Mickael; Reginster, Jean-Yves

    2017-09-07

    There is a paucity of research that projects the public health and economic impact of healthcare interventions in the future. In this study, we aimed to estimate the public health and economic impact of vitamin D fortified dairy products for the years 2020, 2030, 2040, 2050 and 2060. We used a previously validated Markov microsimulation model that was designed to assess the public health and economic impact of dairy products for fracture prevention in the French general population aged over 60 years in the year 2015. The expected benefit (in terms of fractures prevented) of the recommended intake of dairy products compared to the absence of appropriate intake is expected to increase by 63% in 2040 and by 85% in 2060. The cost per quality-adjusted life years gained of the appropriate intake of dairy products is expected to decrease from €58,244 in 2015 to €42,616 in 2060. The potential public health and economic benefits of vitamin D fortified dairy products is expected to substantially increase in the future, especially in the population aged over 80 years. Decision makers should be aware of the current and future potential benefits of dairy products to protect bone fractures.

  17. "Lost milk?": Counting the economic value of breast milk in gross domestic product.

    PubMed

    Smith, J P

    2013-11-01

    The contribution of breastfeeding and mothers milk to the economy is invisible in economic statistics. This article demonstrates how the economic value of human milk production can be included in economic statistics such as gross domestic product (GDP) and provides estimates for Australia, the United States, and Norway. The contribution of human milk and lactation to GDP in these countries is estimated using United Nations (System of National Accounting) guidelines and conventional economic valuation approaches to measuring production in GDP. In Australia, current human milk production levels exceed $3 billion annually. The United States has the potential to produce human milk worth more than US$110 billion a year, but currently nearly two thirds of this value is lost due to premature weaning. In Norway, production valued at US$907 million annually is 60% of its potential value. The potential loss of economic value from not protecting women's lactation and milk production from competing market pressures is large. Failure to account for mothers' milk production in GDP and other economic data has important consequences for public policy. The invisibility of human milk reduces the perceived importance of programs and regulations that protect and support women to breastfeed. The value of human milk can be measured using accepted international guidelines for calculating national income and production. It is quantitatively nontrivial and should be counted in GDP.

  18. Global water resources modeling with an integrated model of the social-economic-environmental system

    NASA Astrophysics Data System (ADS)

    Davies, Evan G. R.; Simonovic, Slobodan P.

    2011-06-01

    Awareness of increasing water scarcity has driven efforts to model global water resources for improved insight into water resources infrastructure and management strategies. Most water resources models focus explicitly on water systems and represent socio-economic and environmental change as external drivers. In contrast, the system dynamics-based integrated assessment model employed here, ANEMI, incorporates dynamic representations of these systems, so that their broader changes affect and are affected by water resources systems through feedbacks. Sectors in ANEMI therefore include the global climate system, carbon cycle, economy, population, land use and agriculture, and novel versions of the hydrological cycle, global water use and water quality. Since the model focus is on their interconnections through explicit nonlinear feedbacks, simulations with ANEMI provide insight into the nature and structure of connections between water resources and socio-economic and environmental change. Of particular interest to water resources researchers and modelers will be the simulated effects of a new water stress definition that incorporates both water quality and water quantity effects into the measurement of water scarcity. Five simulation runs demonstrate the value of wastewater treatment and reuse programs and the feedback-effects of irrigated agriculture and greater consumption of animal products.

  19. Environmental-Economic Assessment Of Generation, Flow And Efficiency Of Use Of Production And Consumption Waste

    NASA Astrophysics Data System (ADS)

    Mikhailov, V. G.; Golofastova, N. N.; Galanina, T. V.; Koroleva, T. G.; Mikhailova, Ya S.

    2017-01-01

    The article deals with the issues of environmental and economic analysis of industrial and economic activities of an enterprise to assess the generation, flow and efficiency of production and consumption waste. The purpose of research is the analysis and the development of theoretical propositions for the functioning of the system of environmental and economic indicators for the effective management of production and consumption waste in the enterprise. The analysis of the existing systems of environmental and economic indicators taking into consideration the industry characteristics and the types of negative impacts is carried out. The main result of the study is the development of the system of environmental and economic indicators of production and consumption waste, adapted to the modern requirements. The results of the study can be recommended to support the effective management decision-making concerning waste management and the establishment of appropriate infrastructure.

  20. A conceptual framework for economic optimization of single hazard surveillance in livestock production chains.

    PubMed

    Guo, Xuezhen; Claassen, G D H; Oude Lansink, A G J M; Saatkamp, H W

    2014-06-01

    Economic analysis of hazard surveillance in livestock production chains is essential for surveillance organizations (such as food safety authorities) when making scientifically based decisions on optimization of resource allocation. To enable this, quantitative decision support tools are required at two levels of analysis: (1) single-hazard surveillance system and (2) surveillance portfolio. This paper addresses the first level by presenting a conceptual approach for the economic analysis of single-hazard surveillance systems. The concept includes objective and subjective aspects of single-hazard surveillance system analysis: (1) a simulation part to derive an efficient set of surveillance setups based on the technical surveillance performance parameters (TSPPs) and the corresponding surveillance costs, i.e., objective analysis, and (2) a multi-criteria decision making model to evaluate the impacts of the hazard surveillance, i.e., subjective analysis. The conceptual approach was checked for (1) conceptual validity and (2) data validity. Issues regarding the practical use of the approach, particularly the data requirement, were discussed. We concluded that the conceptual approach is scientifically credible for economic analysis of single-hazard surveillance systems and that the practicability of the approach depends on data availability. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. A process economic assessment of hydrocarbon biofuels production using chemoautotrophic organisms

    SciTech Connect

    Khan, NE; Myers, JA; Tuerk, AL; Curtis, WR

    2014-11-01

    Economic analysis of an ARPA-e Electrofuels (http://arpa-e.energy.gov/?q=arpa-e-programs/electrofuels) process is presented, utilizing metabolically engineered Rhodobacter capsulatus or Ralstonia eutropha to produce the C30+ hydrocarbon fuel, botryococcene, from hydrogen, carbon dioxide, and oxygen. The analysis is based on an Aspen plus (R) bioreactor model taking into account experimentally determined Rba. capsulatus and Rls. eutropha growth and maintenance requirements, reactor residence time, correlations for gas-liquid mass-transfer coefficient, gas composition, and specific cellular fuel productivity. Based on reactor simulation results encompassing technically relevant parameter ranges, the capital and operating costs of the process were estimated for 5000 bbl-fuel/day plant and used to predict fuel cost. Under the assumptions used in this analysis and crude oil prices, the Levelized Cost of Electricity (LCOE) required for economic feasibility must be less than 2(sic)/kWh. While not feasible under current market prices and costs, this work identifies key variables impacting process cost and discusses potential alternative paths toward economic feasibility. (C) 2014 Elsevier Ltd. All rights reserved.

  2. A process economic assessment of hydrocarbon biofuels production using chemoautotrophic organisms.

    PubMed

    Khan, Nymul E; Myers, John A; Tuerk, Amalie L; Curtis, Wayne R

    2014-11-01

    Economic analysis of an ARPA-e Electrofuels (http://arpa-e.energy.gov/?q=arpa-e-programs/electrofuels) process is presented, utilizing metabolically engineered Rhodobacter capsulatus or Ralstonia eutropha to produce the C30+ hydrocarbon fuel, botryococcene, from hydrogen, carbon dioxide, and oxygen. The analysis is based on an Aspen plus® bioreactor model taking into account experimentally determined Rba. capsulatus and Rls. eutropha growth and maintenance requirements, reactor residence time, correlations for gas-liquid mass-transfer coefficient, gas composition, and specific cellular fuel productivity. Based on reactor simulation results encompassing technically relevant parameter ranges, the capital and operating costs of the process were estimated for 5000 bbl-fuel/day plant and used to predict fuel cost. Under the assumptions used in this analysis and crude oil prices, the Levelized Cost of Electricity (LCOE) required for economic feasibility must be less than 2¢/kWh. While not feasible under current market prices and costs, this work identifies key variables impacting process cost and discusses potential alternative paths toward economic feasibility.

  3. Economic analysis of royalactin production under uncertainty: Evaluating the effect of parameter optimization

    PubMed Central

    Torres‐Acosta, Mario A.; Aguilar‐Yañez, Jose M.; Rito‐Palomares, Marco

    2015-01-01

    Royalactin is a protein with several different potential uses in humans. Research, in insects and in mammalian cells, has shown that it can accelerate cell division and prevent apoptosis. The method of action is through the use of the epidermal growth factor receptor, which is present in humans. Potential use in humans could be to lower cholesterolemic levels in blood, and to elicit similar effects to those seen in bees, e.g., increased lifespan. Mass production of Royalactin has not been accomplished, though a recent article presented a Pichia pastoris fermentation and recovery by aqueous two‐phase systems at laboratory scale as a possible basis for production. Economic modelling is a useful tool with which compare possible outcomes for the production of such a molecule and in particular, to locate areas where additional research is needed and optimization may be required. This study uses the BioSolve software to perform an economic analysis on the scale‐up of the putative process for Royalactin. The key parameters affecting the cost of production were located via a sensitivity analysis and then evaluated by Monte Carlo analysis. Results show that if titer is not optimized the strategy to maintain a low cost of goods is process oriented. After optimization of this parameter the strategy changes to a product‐oriented and the target output becomes the critical parameter determining the cost of goods. This study serves to provide a framework for the evaluation of strategies for future production of Royalactin, by analyzing the factors that influence its cost of manufacture. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:744–749, 2015 PMID:25737309

  4. Economic decision making and the application of nonparametric prediction models

    USGS Publications Warehouse

    Attanasi, E.D.; Coburn, T.C.; Freeman, P.A.

    2008-01-01

    Sustained increases in energy prices have focused attention on gas resources in low-permeability shale or in coals that were previously considered economically marginal. Daily well deliverability is often relatively small, although the estimates of the total volumes of recoverable resources in these settings are often large. Planning and development decisions for extraction of such resources must be areawide because profitable extraction requires optimization of scale economies to minimize costs and reduce risk. For an individual firm, the decision to enter such plays depends on reconnaissance-level estimates of regional recoverable resources and on cost estimates to develop untested areas. This paper shows how simple nonparametric local regression models, used to predict technically recoverable resources at untested sites, can be combined with economic models to compute regional-scale cost functions. The context of the worked example is the Devonian Antrim-shale gas play in the Michigan basin. One finding relates to selection of the resource prediction model to be used with economic models. Models chosen because they can best predict aggregate volume over larger areas (many hundreds of sites) smooth out granularity in the distribution of predicted volumes at individual sites. This loss of detail affects the representation of economic cost functions and may affect economic decisions. Second, because some analysts consider unconventional resources to be ubiquitous, the selection and order of specific drilling sites may, in practice, be determined arbitrarily by extraneous factors. The analysis shows a 15-20% gain in gas volume when these simple models are applied to order drilling prospects strategically rather than to choose drilling locations randomly. Copyright ?? 2008 Society of Petroleum Engineers.

  5. Economic decision making and the application of nonparametric prediction models

    USGS Publications Warehouse

    Attanasi, E.D.; Coburn, T.C.; Freeman, P.A.

    2007-01-01

    Sustained increases in energy prices have focused attention on gas resources in low permeability shale or in coals that were previously considered economically marginal. Daily well deliverability is often relatively small, although the estimates of the total volumes of recoverable resources in these settings are large. Planning and development decisions for extraction of such resources must be area-wide because profitable extraction requires optimization of scale economies to minimize costs and reduce risk. For an individual firm the decision to enter such plays depends on reconnaissance level estimates of regional recoverable resources and on cost estimates to develop untested areas. This paper shows how simple nonparametric local regression models, used to predict technically recoverable resources at untested sites, can be combined with economic models to compute regional scale cost functions. The context of the worked example is the Devonian Antrim shale gas play, Michigan Basin. One finding relates to selection of the resource prediction model to be used with economic models. Models which can best predict aggregate volume over larger areas (many hundreds of sites) may lose granularity in the distribution of predicted volumes at individual sites. This loss of detail affects the representation of economic cost functions and may affect economic decisions. Second, because some analysts consider unconventional resources to be ubiquitous, the selection and order of specific drilling sites may, in practice, be determined by extraneous factors. The paper also shows that when these simple prediction models are used to strategically order drilling prospects, the gain in gas volume over volumes associated with simple random site selection amounts to 15 to 20 percent. It also discusses why the observed benefit of updating predictions from results of new drilling, as opposed to following static predictions, is somewhat smaller. Copyright 2007, Society of Petroleum Engineers.

  6. Modelling the interaction between flooding events and economic growth

    NASA Astrophysics Data System (ADS)

    Grames, Johanna; Fürnkranz-Prskawetz, Alexia; Grass, Dieter; Viglione, Alberto; Blöschl, Günter

    2016-04-01

    Recently socio-hydrology models have been proposed to analyze the interplay of community risk-coping culture, flooding damage and economic growth. These models descriptively explain the feedbacks between socio-economic development and natural disasters such as floods. Complementary to these descriptive models, we develop a dynamic optimization model, where the inter-temporal decision of an economic agent interacts with the hydrological system. This interdisciplinary approach matches with the goals of Panta Rhei i.e. to understand feedbacks between hydrology and society. It enables new perspectives but also shows limitations of each discipline. Young scientists need mentors from various scientific backgrounds to learn their different research approaches and how to best combine them such that interdisciplinary scientific work is also accepted by different science communities. In our socio-hydrology model we apply a macro-economic decision framework to a long-term flood-scenario. We assume a standard macro-economic growth model where agents derive utility from consumption and output depends on physical capital that can be accumulated through investment. To this framework we add the occurrence of flooding events which will destroy part of the capital. We identify two specific periodic long term solutions and denote them rich and poor economies. Whereas rich economies can afford to invest in flood defense and therefore avoid flood damage and develop high living standards, poor economies prefer consumption instead of investing in flood defense capital and end up facing flood damages every time the water level rises. Nevertheless, they manage to sustain at least a low level of physical capital. We identify optimal investment strategies and compare simulations with more frequent and more intense high water level events.

  7. A generic bio-economic farm model for environmental and economic assessment of agricultural systems.

    PubMed

    Janssen, Sander; Louhichi, Kamel; Kanellopoulos, Argyris; Zander, Peter; Flichman, Guillermo; Hengsdijk, Huib; Meuter, Eelco; Andersen, Erling; Belhouchette, Hatem; Blanco, Maria; Borkowski, Nina; Heckelei, Thomas; Hecker, Martin; Li, Hongtao; Oude Lansink, Alfons; Stokstad, Grete; Thorne, Peter; van Keulen, Herman; van Ittersum, Martin K

    2010-12-01

    Bio-economic farm models are tools to evaluate ex-post or to assess ex-ante the impact of policy and technology change on agriculture, economics and environment. Recently, various BEFMs have been developed, often for one purpose or location, but hardly any of these models are re-used later for other purposes or locations. The Farm System Simulator (FSSIM) provides a generic framework enabling the application of BEFMs under various situations and for different purposes (generating supply response functions and detailed regional or farm type assessments). FSSIM is set up as a component-based framework with components representing farmer objectives, risk, calibration, policies, current activities, alternative activities and different types of activities (e.g., annual and perennial cropping and livestock). The generic nature of FSSIM is evaluated using five criteria by examining its applications. FSSIM has been applied for different climate zones and soil types (criterion 1) and to a range of different farm types (criterion 2) with different specializations, intensities and sizes. In most applications FSSIM has been used to assess the effects of policy changes and in two applications to assess the impact of technological innovations (criterion 3). In the various applications, different data sources, level of detail (e.g., criterion 4) and model configurations have been used. FSSIM has been linked to an economic and several biophysical models (criterion 5). The model is available for applications to other conditions and research issues, and it is open to be further tested and to be extended with new components, indicators or linkages to other models.

  8. A Generic Bio-Economic Farm Model for Environmental and Economic Assessment of Agricultural Systems

    PubMed Central

    Louhichi, Kamel; Kanellopoulos, Argyris; Zander, Peter; Flichman, Guillermo; Hengsdijk, Huib; Meuter, Eelco; Andersen, Erling; Belhouchette, Hatem; Blanco, Maria; Borkowski, Nina; Heckelei, Thomas; Hecker, Martin; Li, Hongtao; Oude Lansink, Alfons; Stokstad, Grete; Thorne, Peter; van Keulen, Herman; van Ittersum, Martin K.

    2010-01-01

    Bio-economic farm models are tools to evaluate ex-post or to assess ex-ante the impact of policy and technology change on agriculture, economics and environment. Recently, various BEFMs have been developed, often for one purpose or location, but hardly any of these models are re-used later for other purposes or locations. The Farm System Simulator (FSSIM) provides a generic framework enabling the application of BEFMs under various situations and for different purposes (generating supply response functions and detailed regional or farm type assessments). FSSIM is set up as a component-based framework with components representing farmer objectives, risk, calibration, policies, current activities, alternative activities and different types of activities (e.g., annual and perennial cropping and livestock). The generic nature of FSSIM is evaluated using five criteria by examining its applications. FSSIM has been applied for different climate zones and soil types (criterion 1) and to a range of different farm types (criterion 2) with different specializations, intensities and sizes. In most applications FSSIM has been used to assess the effects of policy changes and in two applications to assess the impact of technological innovations (criterion 3). In the various applications, different data sources, level of detail (e.g., criterion 4) and model configurations have been used. FSSIM has been linked to an economic and several biophysical models (criterion 5). The model is available for applications to other conditions and research issues, and it is open to be further tested and to be extended with new components, indicators or linkages to other models. PMID:21113782

  9. Crop diversity effects on productivity and economic returns under dryland agriculture

    USDA-ARS?s Scientific Manuscript database

    Increasing crop diversity has been identified as a method to improve agronomic performance of cropping systems and increase provision of ecosystem services. However, there is a need to understand the economic performance of more diverse cropping systems. Crop productivity and economic net returns we...

  10. On the Market for Principles of Economics Textbooks: Innovation and Product Differentiation--A Response.

    ERIC Educational Resources Information Center

    Schiller, Bradley

    1988-01-01

    Responding to Stiglitz's article "On the Market for Principles of Economics Textbooks: Innovation and Product Differentiation," Schiller disputes the claim that there is growing dissatisfaction with textbooks, stating that the central issue in the debate is "how best to teach economic principles." Discusses the importance of…

  11. An Economic Model of Workplace Mobbing in Academe

    ERIC Educational Resources Information Center

    Faria, Joao Ricardo; Mixon, Franklin G., Jr.; Salter, Sean P.

    2012-01-01

    Workplace bullying or mobbing can be defined as the infliction of various forms of abuse (e.g., verbal, emotional, psychological) against a colleague or subordinate by one or more other members of a workplace. Even in the presence of academic tenure, workplace mobbing remains a prevalent issue in academe. This study develops an economic model that…

  12. Using STELLA Simulation Models to Teach Natural Resource Economics

    ERIC Educational Resources Information Center

    Dissanayake, Sahan T. M.

    2016-01-01

    In this article, the author discusses how graphical simulation models created using STELLA software can be used to present natural resource systems in an intuitive way in undergraduate natural resource economics classes based on his experiences at a leading research university, a state university, and a leading liberal arts college in the United…

  13. Student Migration to Online Education: An Economic Model

    ERIC Educational Resources Information Center

    Eisenhauer, Joseph G.

    2013-01-01

    The popularity of distance education has increasingly led universities to consider expanding their online offerings. Remarkably few financial models have been presented for online courses, however, and fewer still have investigated the economic consequences of the migration, or cross-over, of students from traditional classes within the…

  14. Using STELLA Simulation Models to Teach Natural Resource Economics

    ERIC Educational Resources Information Center

    Dissanayake, Sahan T. M.

    2016-01-01

    In this article, the author discusses how graphical simulation models created using STELLA software can be used to present natural resource systems in an intuitive way in undergraduate natural resource economics classes based on his experiences at a leading research university, a state university, and a leading liberal arts college in the United…

  15. Childhood Adultification in Economically Disadvantaged Families: A Conceptual Model

    ERIC Educational Resources Information Center

    Burton, Linda

    2007-01-01

    This article presents an emergent conceptual model of childhood adultification and economic disadvantage derived from 5 longitudinal ethnographies of children and adolescents growing up in low-income families. Childhood adultification involves contextual, social, and developmental processes in which youth are prematurely, and often…

  16. An Economic Model of Workplace Mobbing in Academe

    ERIC Educational Resources Information Center

    Faria, Joao Ricardo; Mixon, Franklin G., Jr.; Salter, Sean P.

    2012-01-01

    Workplace bullying or mobbing can be defined as the infliction of various forms of abuse (e.g., verbal, emotional, psychological) against a colleague or subordinate by one or more other members of a workplace. Even in the presence of academic tenure, workplace mobbing remains a prevalent issue in academe. This study develops an economic model that…

  17. Biomass feedstock production systems: economic and environmental benefits

    Treesearch

    Mark D. Coleman; John A. Stanturf

    2006-01-01

    The time is ripe for expanding bioenergy production capacity and developing a bio-based economy. Modern society has created unprecedented demands for energy and chemical products that are predominately based on geologic sources. However, there is a growing consensus that constraints on the supply of petroleum and the negative environmental consequences of burning...

  18. Food Production and Services. Performance Objectives. Criterion Measures. Home Economics.

    ERIC Educational Resources Information Center

    Bryant, EuDell H.; And Others

    Several intermediate performance objectives and corresponding criterion measures are listed for each of eight terminal objectives for a food production and services course, which is designed to provide students with an opportunity to express and practice a broad range of food production and service occupations. Major concepts covered include…

  19. Food Production and Services. Performance Objectives. Criterion Measures. Home Economics.

    ERIC Educational Resources Information Center

    Bryant, EuDell H.; And Others

    Several intermediate performance objectives and corresponding criterion measures are listed for each of eight terminal objectives for a food production and services course, which is designed to provide students with an opportunity to express and practice a broad range of food production and service occupations. Major concepts covered include…

  20. The economics of biomass production in the United States

    SciTech Connect

    Graham, R.L.; Walsh, M.E.; Lichtenberg, E.; Roningen, V.O.; Shapouri, H.

    1995-12-31

    Biomass crops (e.g. poplar, willow, switchgrass) could become important feedstocks for power, liquid fuel, and chemical production. This paper presents estimates of the potential production of biomass in the US under a range of assumptions. Estimates of potential biomass crop yields and production costs from the Department of Energy`s (DOE) Oak Ridge National Laboratories (ORNL) are combined with measures of land rents from USDA`s Conservation Reserve Program (CRP), to estimate a competitive supply of biomass wood and grass crops. Estimates are made for one potential biomass use--electric power production--where future costs of electricity production from competing fossil fuels set the demand price. The paper outlines the methodology used and limitations of the analysis.

  1. Economic assessment of different mulches in conventional and water-saving rice production systems.

    PubMed

    Jabran, Khawar; Hussain, Mubshar; Fahad, Shah; Farooq, Muhammad; Bajwa, Ali Ahsan; Alharrby, Hesham; Nasim, Wajid

    2016-05-01

    Water-saving rice production systems including alternate wetting and drying (AWD) and aerobic rice (AR) are being increasingly adopted by growers due to global water crises. Application of natural and artificial mulches may further improve water economy of water-saving rice production systems. Conventionally flooded rice (CFR) system has been rarely compared with AWD and AR in terms of economic returns. In this 2-year field study, we compared CFR with AWD and AR (with and without straw and plastic mulches) for the cost of production and economic benefits. Results indicated that CFR had a higher production cost than AWD and AR. However, application of mulches increased the cost of production of AWD and AR production systems where plastic mulch was expensive than straw mulch. Although the mulching increased the cost of production for AWD and AR, the gross income of these systems was also improved significantly. The gross income from mulched plots of AWD and AR was higher than non-mulched plots of the same systems. In conclusion, AWD and AR effectively reduce cost of production by economizing the water use. However, the use of natural and artificial mulches in such water-saving environments further increased the economic returns. The maximized economic returns by using straw mulch in water-saving rice production systems definitely have pragmatic implications for sustainable agriculture.

  2. Proposed Consent Agreement and Final Order: Norton Sound Economic Development Corporation dba Norton Sound Seafood Products

    EPA Pesticide Factsheets

    EPA's proposed administrative penalty settlement with Norton Sound Economic Development Corporation d/b/a Norton Sound Seafood Products for violations of the Clean Water Act at its facility located in Nome, Alaska.

  3. Economics.

    ERIC Educational Resources Information Center

    Kemp, Rodger

    This course presents basic economic concepts and explores issues such as how goods and services are produced and distributed, what affects costs and profits, and how wealth is spread around or concentrated. The course is designed to be used with students enrolled in an adult high school diploma program; course content is appropriate to meet social…

  4. Project Economic Stew: A Study of Poultry and Rice. A Third-grade Economics Project [and] A Bird's Eye View of an Economic Stew: A Study of Poultry and Rice Production in Arkansas.

    ERIC Educational Resources Information Center

    Fox, Penny

    An economics project for third grade children is described and lessons for teaching basic economic concepts are provided. In the first semester, students studied basic economic concepts; in the second semester, they learned about the origin, production, and distribution of rice and poultry and how these products affect the local and state…

  5. Uncertainty and validation of health economic decision models.

    PubMed

    Kim, Lois G; Thompson, Simon G

    2010-01-01

    Health economic decision models are based on specific assumptions relating to model structure and parameter estimation. Validation of these models is recommended as an indicator of reliability, but is not commonly reported. Furthermore, models derived from different data and employing different assumptions may produce a variety of results.A Markov model for evaluating the long-term cost-effectiveness of screening for abdominal aortic aneurysm is described. Internal, prospective and external validations are carried out using individual participant data from two randomised trials. Validation is assessed in terms of total numbers and timings of key events, and total costs and life-years. Since the initial model validates well only internally, two further models are developed that better fit the prospective and external validation data. All three models are then extrapolated to a life-time horizon, producing cost-effectiveness estimates ranging from pound1600 to pound4200 per life-year gained.Parameter uncertainty is now commonly addressed in health economic decision modelling. However, the derivation of models from different data sources adds another level of uncertainty. This extra uncertainty should be recognised in practical decision-making and, where possible, specifically investigated through independent model validation.

  6. Impact of pretreatment and downstream processing technologies on economics and energy in cellulosic ethanol production

    PubMed Central

    2011-01-01

    Background While advantages of biofuel have been widely reported, studies also highlight the challenges in large scale production of biofuel. Cost of ethanol and process energy use in cellulosic ethanol plants are dependent on technologies used for conversion of feedstock. Process modeling can aid in identifying techno-economic bottlenecks in a production process. A comprehensive techno-economic analysis was performed for conversion of cellulosic feedstock to ethanol using some of the common pretreatment technologies: dilute acid, dilute alkali, hot water and steam explosion. Detailed process models incorporating feedstock handling, pretreatment, simultaneous saccharification and co-fermentation, ethanol recovery and downstream processing were developed using SuperPro Designer. Tall Fescue (Festuca arundinacea Schreb) was used as a model feedstock. Results Projected ethanol yields were 252.62, 255.80, 255.27 and 230.23 L/dry metric ton biomass for conversion process using dilute acid, dilute alkali, hot water and steam explosion pretreatment technologies respectively. Price of feedstock and cellulose enzymes were assumed as $50/metric ton and 0.517/kg broth (10% protein in broth, 600 FPU/g protein) respectively. Capital cost of ethanol plants processing 250,000 metric tons of feedstock/year was $1.92, $1.73, $1.72 and $1.70/L ethanol for process using dilute acid, dilute alkali, hot water and steam explosion pretreatment respectively. Ethanol production cost of $0.83, $0.88, $0.81 and $0.85/L ethanol was estimated for production process using dilute acid, dilute alkali, hot water and steam explosion pretreatment respectively. Water use in the production process using dilute acid, dilute alkali, hot water and steam explosion pretreatment was estimated 5.96, 6.07, 5.84 and 4.36 kg/L ethanol respectively. Conclusions Ethanol price and energy use were highly dependent on process conditions used in the ethanol production plant. Potential for significant ethanol cost

  7. Impact of pretreatment and downstream processing technologies on economics and energy in cellulosic ethanol production.

    PubMed

    Kumar, Deepak; Murthy, Ganti S

    2011-09-05

    While advantages of biofuel have been widely reported, studies also highlight the challenges in large scale production of biofuel. Cost of ethanol and process energy use in cellulosic ethanol plants are dependent on technologies used for conversion of feedstock. Process modeling can aid in identifying techno-economic bottlenecks in a production process. A comprehensive techno-economic analysis was performed for conversion of cellulosic feedstock to ethanol using some of the common pretreatment technologies: dilute acid, dilute alkali, hot water and steam explosion. Detailed process models incorporating feedstock handling, pretreatment, simultaneous saccharification and co-fermentation, ethanol recovery and downstream processing were developed using SuperPro Designer. Tall Fescue (Festuca arundinacea Schreb) was used as a model feedstock. Projected ethanol yields were 252.62, 255.80, 255.27 and 230.23 L/dry metric ton biomass for conversion process using dilute acid, dilute alkali, hot water and steam explosion pretreatment technologies respectively. Price of feedstock and cellulose enzymes were assumed as $50/metric ton and 0.517/kg broth (10% protein in broth, 600 FPU/g protein) respectively. Capital cost of ethanol plants processing 250,000 metric tons of feedstock/year was $1.92, $1.73, $1.72 and $1.70/L ethanol for process using dilute acid, dilute alkali, hot water and steam explosion pretreatment respectively. Ethanol production cost of $0.83, $0.88, $0.81 and $0.85/L ethanol was estimated for production process using dilute acid, dilute alkali, hot water and steam explosion pretreatment respectively. Water use in the production process using dilute acid, dilute alkali, hot water and steam explosion pretreatment was estimated 5.96, 6.07, 5.84 and 4.36 kg/L ethanol respectively. Ethanol price and energy use were highly dependent on process conditions used in the ethanol production plant. Potential for significant ethanol cost reductions exist in increasing

  8. Maximum likelihood estimation of finite mixture model for economic data

    NASA Astrophysics Data System (ADS)

    Phoong, Seuk-Yen; Ismail, Mohd Tahir

    2014-06-01

    Finite mixture model is a mixture model with finite-dimension. This models are provides a natural representation of heterogeneity in a finite number of latent classes. In addition, finite mixture models also known as latent class models or unsupervised learning models. Recently, maximum likelihood estimation fitted finite mixture models has greatly drawn statistician's attention. The main reason is because maximum likelihood estimation is a powerful statistical method which provides consistent findings as the sample sizes increases to infinity. Thus, the application of maximum likelihood estimation is used to fit finite mixture model in the present paper in order to explore the relationship between nonlinear economic data. In this paper, a two-component normal mixture model is fitted by maximum likelihood estimation in order to investigate the relationship among stock market price and rubber price for sampled countries. Results described that there is a negative effect among rubber price and stock market price for Malaysia, Thailand, Philippines and Indonesia.

  9. The economic efficiency of conservation measures for amphibians in organic farming--results from bio-economic modelling.

    PubMed

    Schuler, Johannes; Sattler, Claudia; Helmecke, Angela; Zander, Peter; Uthes, Sandra; Bachinger, Johann; Stein-Bachinger, Karin

    2013-01-15

    This paper presents a whole farm bio-economic modelling approach for the assessment and optimisation of amphibian conservation conditions applied at the example of a large scale organic farm in North-Eastern Germany. The assessment focuses mainly on the habitat quality as affected by conservation measures such as through specific adapted crop production activities (CPA) and in-field buffer strips for the European tree frog (Hyla arborea), considering also interrelations with other amphibian species (i.e. common spadefoot toad (Pelobates fuscus), fire-bellied toad (Bombina bombina)). The aim of the approach is to understand, analyse and optimize the relationships between the ecological and economic performance of an organic farming system, based on the expectation that amphibians are differently impacted by different CPAs. The modelling system consists of a set of different sub-models that generate a farm model on the basis of environmentally evaluated CPAs. A crop-rotation sub-model provides a set of agronomically sustainable crop rotations that ensures overall sufficient nitrogen supply and controls weed, pest and disease infestations. An economic sub-model calculates the gross margins for each possible CPA including costs of inputs such as labour and machinery. The conservation effects of the CPAs are assessed with an ecological sub-model evaluates the potential negative or positive effect that each work step of a CPA has on amphibians. A mathematical programming sub-model calculates the optimal farm organization taking into account the limited factors of the farm (e.g. labour, land) as well as ecological improvements. In sequential model runs, the habitat quality is to be improved by the model, while the highest possible gross margin is still to be achieved. The results indicate that the model can be used to show the scope of action that a farmer has to improve habitat quality by reducing damage to amphibian population on its land during agricultural activities

  10. Cotton production and water quality: Economic and environmental effects of pollution prevention. Agricultural economic report

    SciTech Connect

    Crutchfield, S.R.; Ribaudo, M.O.; Hansen, L.T.; Quiroga, R.

    1992-12-01

    Cotton production, compared with other crops, is less likely to cause erosion-induced water-quality problems because cotton acreage is not the major source of erosion in most regions. For cotton production, the most widespread potential damages to water quality are nitrates from fertilizer polluting ground water and pesticides contaminating surface water. This damage could be reduced by restricting chemical and fertilizer use on all cotton production, but doing so could reduce cotton yields and raise cotton prices. The same level of water-quality improvement could be achieved at less cost by targeting the chemical use or erosion restrictions only to cotton farms with the most vulnerable soils. Data come from a 1989 USDA survey of cotton producers.

  11. Modeling human behavior in economics and social science.

    PubMed

    Dolfin, M; Leonida, L; Outada, N

    2017-06-29

    The complex interactions between human behaviors and social economic sciences is critically analyzed in this paper in view of possible applications of mathematical modeling as an attainable interdisciplinary approach to understand and simulate the aforementioned dynamics. The quest is developed along three steps: Firstly an overall analysis of social and economic sciences indicates the main requirements that a contribution of mathematical modeling should bring to these sciences; subsequently the focus moves to an overview of mathematical tools and to the selection of those which appear, according to the authors bias, appropriate to the modeling; finally, a survey of applications is presented looking ahead to research perspectives. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Stochastic effects in a discretized kinetic model of economic exchange

    NASA Astrophysics Data System (ADS)

    Bertotti, M. L.; Chattopadhyay, A. K.; Modanese, G.

    2017-04-01

    Linear stochastic models and discretized kinetic theory are two complementary analytical techniques used for the investigation of complex systems of economic interactions. The former employ Langevin equations, with an emphasis on stock trade; the latter is based on systems of ordinary differential equations and is better suited for the description of binary interactions, taxation and welfare redistribution. We propose a new framework which establishes a connection between the two approaches by introducing random fluctuations into the kinetic model based on Langevin and Fokker-Planck formalisms. Numerical simulations of the resulting model indicate positive correlations between the Gini index and the total wealth, that suggest a growing inequality with increasing income. Further analysis shows, in the presence of a conserved total wealth, a simultaneous decrease in inequality as social mobility increases, in conformity with economic data.

  13. A neuro-computational model of economic decisions.

    PubMed

    Rustichini, Aldo; Padoa-Schioppa, Camillo

    2015-09-01

    Neuronal recordings and lesion studies indicate that key aspects of economic decisions take place in the orbitofrontal cortex (OFC). Previous work identified in this area three groups of neurons encoding the offer value, the chosen value, and the identity of the chosen good. An important and open question is whether and how decisions could emerge from a neural circuit formed by these three populations. Here we adapted a biophysically realistic neural network previously proposed for perceptual decisions (Wang XJ. Neuron 36: 955-968, 2002; Wong KF, Wang XJ. J Neurosci 26: 1314-1328, 2006). The domain of economic decisions is significantly broader than that for which the model was originally designed, yet the model performed remarkably well. The input and output nodes of the network were naturally mapped onto two groups of cells in OFC. Surprisingly, the activity of interneurons in the network closely resembled that of the third group of cells, namely, chosen value cells. The model reproduced several phenomena related to the neuronal origins of choice variability. It also generated testable predictions on the excitatory/inhibitory nature of different neuronal populations and on their connectivity. Some aspects of the empirical data were not reproduced, but simple extensions of the model could overcome these limitations. These results render a biologically credible model for the neuronal mechanisms of economic decisions. They demonstrate that choices could emerge from the activity of cells in the OFC, suggesting that chosen value cells directly participate in the decision process. Importantly, Wang's model provides a platform to investigate the implications of neuroscience results for economic theory.

  14. A neuro-computational model of economic decisions

    PubMed Central

    Rustichini, Aldo

    2015-01-01

    Neuronal recordings and lesion studies indicate that key aspects of economic decisions take place in the orbitofrontal cortex (OFC). Previous work identified in this area three groups of neurons encoding the offer value, the chosen value, and the identity of the chosen good. An important and open question is whether and how decisions could emerge from a neural circuit formed by these three populations. Here we adapted a biophysically realistic neural network previously proposed for perceptual decisions (Wang XJ. Neuron 36: 955–968, 2002; Wong KF, Wang XJ. J Neurosci 26: 1314–1328, 2006). The domain of economic decisions is significantly broader than that for which the model was originally designed, yet the model performed remarkably well. The input and output nodes of the network were naturally mapped onto two groups of cells in OFC. Surprisingly, the activity of interneurons in the network closely resembled that of the third group of cells, namely, chosen value cells. The model reproduced several phenomena related to the neuronal origins of choice variability. It also generated testable predictions on the excitatory/inhibitory nature of different neuronal populations and on their connectivity. Some aspects of the empirical data were not reproduced, but simple extensions of the model could overcome these limitations. These results render a biologically credible model for the neuronal mechanisms of economic decisions. They demonstrate that choices could emerge from the activity of cells in the OFC, suggesting that chosen value cells directly participate in the decision process. Importantly, Wang's model provides a platform to investigate the implications of neuroscience results for economic theory. PMID:26063776

  15. Economical Production of Pu-238: NIAC Phase I Final Report

    NASA Technical Reports Server (NTRS)

    Howe, Steven D.; Crawford, Douglas; Navarro, Jorge; O'Brien, Robert C.; Katalenich, Jeff; Ring, Terry

    2016-01-01

    All space exploration missions traveling beyond Jupiter must use radioisotopic power sources for electrical power. The best isotope to power these sources is plutonium-238 (Pu-238). The US supply of Pu-238 is almost exhausted and will be gone within the next decade. The Department of Energy has initiated a production program with a $10M allocation from NASA but the cost is estimated at over $100M to get to production levels. The Center for Space Nuclear Research (CSNR) has conceived of a potentially better process to produce Pu-238 earlier and for significantly less cost. Potentially, the front end capital costs could be provided by private industry such that the government only had to pay for the product produced. In the Phase I NIAC (NASA Innovative Advanced Concepts) grant, the CSNR has evaluated the feasibility of using a low power, commercially available nuclear reactor to produce 1.5 kg of Pu-238 per year. The impact on the neutronics of the reactor have been assessed, the amount of Neptunium target material estimated, and the production rates calculated. In addition, the size of the post-irradiation processing facility has been established. Finally, as the study progressed, a new method for fabricating the Pu-238 product into the form used for power sources has been identified to reduce the cost of the final product. In short, the concept appears to be viable, can produce the amount of Pu-238 needed to support the NASA missions, can be available within a few years, and will cost significantly less than the current DOE program.

  16. Economic damages of ozone air pollution to crops using combined air quality and GIS modelling

    NASA Astrophysics Data System (ADS)

    Vlachokostas, Ch.; Nastis, S. A.; Achillas, Ch.; Kalogeropoulos, K.; Karmiris, I.; Moussiopoulos, N.; Chourdakis, E.; Banias, G.; Limperi, N.

    2010-09-01

    This study aims at presenting a combined air quality and GIS modelling methodological approach in order to estimate crop damages from photochemical air pollution, depict their spatial resolution and assess the order of magnitude regarding the corresponding economic damages. The analysis is conducted within the Greater Thessaloniki Area, Greece, a Mediterranean territory which is characterised by high levels of photochemical air pollution and considerable agricultural activity. Ozone concentration fields for 2002 and for specific emission reduction scenarios for the year 2010 were estimated with the Ozone Fine Structure model in the area under consideration. Total economic damage to crops turns out to be significant and estimated to be approximately 43 M€ for the reference year. Production of cotton presents the highest economic loss, which is over 16 M€, followed by table tomato (9 M€), rice (4.2 M€), wheat (4 M€) and oilseed rape (2.8 M€) cultivations. Losses are not spread uniformly among farmers and the major losses occur in areas with valuable ozone-sensitive crops. The results are very useful for highlighting the magnitude of the total economic impacts of photochemical air pollution to the area's agricultural sector and can potentially be used for comparison with studies worldwide. Furthermore, spatial analysis of the economic damage could be of importance for governmental authorities and decision makers since it provides an indicative insight, especially if the economic instruments such as financial incentives or state subsidies to farmers are considered.

  17. Multi objectives model to optimise the economical value of agriculture water use in Gaza Strip

    NASA Astrophysics Data System (ADS)

    Ouda, O.; Bardossy, A.

    2003-04-01

    Multi objectives model to optimise the economical value of agriculture water use in Gaza Strip. O. Ouda (1), A. Bárdossy (1) (1) Institut fuer Wasserbau, Universitaet Stuttgart Fax: +49-(0)711-685-4746/ e-mail: omar.ouda@iws.uni-stuttgart.de Key words: Multi objectives model, agriculture water use, and Gaza Strip. ============================================================================ Abstract The Gaza Strip faces a serious water shortage problem, with a present water shortage of about 61 Mm3/year. The problem is projected to become even larger in the future due to a high population growth of about 3.2%. The water deficit is presently covered by abstraction of the groundwater beyond the sustainable yield, where groundwater is the only natural source in Gaza strip. Irrigated agriculture consumed about 60% (90 Mm3/year) of water in Gaza strip. The economical value of water used for agriculture propose is very low in comparison with water opportunity cost of 1 US/m3 , ( seawater desalination cost). A Multi objective optimisation model (MOM) based on mathematical programming techniques aimed to optimise the economical return value of agriculture water use has been formulated, where 20 crops distributed over 16 zones have been considered. The available agriculture area, Available treated wastewater, Local agriculture products demand were considered as constrains. Irrigation water demand for each crop for three meteorological conditions dry, wet and average year, and Average product prices were considered as variables. A modification of the MOM models has been made toward equitable profit distribution (US/hectare) among the different 16 zones, where additional constrain of minimum profit per hectare in each zone has been implemented. Finally a sensitivity analysis for the effect of water price, crop price and crop products demand on the model output has been made. The MOM presents a good analytical basis for policy makers toward optimising the economical return of

  18. Industrial food animal production and global health risks: exploring the ecosystems and economics of avian influenza.

    PubMed

    Leibler, Jessica H; Otte, Joachim; Roland-Holst, David; Pfeiffer, Dirk U; Soares Magalhaes, Ricardo; Rushton, Jonathan; Graham, Jay P; Silbergeld, Ellen K

    2009-03-01

    Many emerging infectious diseases in human populations are associated with zoonotic origins. Attention has often focused on wild animal reservoirs, but most zoonotic pathogens of recent concern to human health either originate in, or are transferred to, human populations from domesticated animals raised for human consumption. Thus, the ecological context of emerging infectious disease comprises two overlapping ecosystems: the natural habitats and populations of wild animals, and the anthropogenically controlled habitats and populations of domesticated species. Intensive food animal production systems and their associated value chains dominate in developed countries and are increasingly important in developing countries. These systems are characterized by large numbers of animals being raised in confinement with high throughput and rapid turnover. Although not typically recognized as such, industrial food animal production generates unique ecosystems -- environments that may facilitate the evolution of zoonotic pathogens and their transmission to human populations. It is often assumed that confined food animal production reduces risks of emerging zoonotic diseases. This article provides evidence suggesting that these industrial systems may increase animal and public health risks unless there is recognition of the specific biosecurity and biocontainment challenges of the industrial model. Moreover, the economic drivers and constraints faced by the industry and its participants must be fully understood in order to inform preventative policy. In order to more effectively reduce zoonotic disease risk from industrial food animal production, private incentives for the implementation of biosecurity must align with public health interests.

  19. The economical production of alcohol fuels from coal-derived synthesis gas: Case studies, design, and economics

    SciTech Connect

    1995-10-01

    This project is a combination of process simulation and catalyst development aimed at identifying the most economical method for converting coal to syngas to linear higher alcohols to be used as oxygenated fuel additives. There are two tasks. The goal of Task 1 is to discover, study, and evaluate novel heterogeneous catalytic systems for the production of oxygenated fuel enhancers from synthesis gas, and to explore, analytically and on the bench scale, novel reactor and process concepts for use in converting syngas to liquid fuel products. The goal of Task 2 is to simulate, by computer, energy efficient and economically efficient processes for converting coal to energy (fuel alcohols and/or power). The primary focus is to convert syngas to fuel alcohols. This report contains results from Task 2. The first step for Task 2 was to develop computer simulations of alternative coal to syngas to linear higher alcohol processes, to evaluate and compare the economics and energy efficiency of these alternative processes, and to make a preliminary determination as to the most attractive process configuration. A benefit of this approach is that simulations will be debugged and available for use when Task 1 results are available. Seven cases were developed using different gasifier technologies, different methods for altering the H{sub 2}/CO ratio of the syngas to the desired 1.1/1, and with the higher alcohol fuel additives as primary products and as by-products of a power generation facility. Texaco, Shell, and Lurgi gasifier designs were used to test gasifying coal. Steam reforming of natural gas, sour gas shift conversion, or pressure swing adsorption were used to alter the H{sub 2}/CO ratio of the syngas. In addition, a case using only natural gas was prepared to compare coal and natural gas as a source of syngas.

  20. Price elasticity of tobacco products among economic classes in India, 2011-2012.

    PubMed

    Selvaraj, Sakthivel; Srivastava, Swati; Karan, Anup

    2015-12-09

    The objectives of this study are to: (1) examine the pattern of price elasticity of three major tobacco products (bidi, cigarette and leaf tobacco) by economic groups of population based on household monthly per capita consumption expenditure in India and (2) assess the effect of tax increases on tobacco consumption and revenue across expenditure groups. Data from the 2011-2012 nationally representative Consumer Expenditure Survey from 101,662 Indian households were used. Households which consumed any tobacco or alcohol product were retained in final models. The study draws theoretical frameworks from a model using the augmented utility function of consumer behaviour, with a two-stage two-equation system of unit values and budget shares. Primary outcome measures were price elasticity of demand for different tobacco products for three hierarchical economic groups of population and change in tax revenue due to changes in tax structure. We finally estimated price elasticity of demand for bidi, cigarette and leaf tobacco and effects of changes in their tax rates on demand for these tobacco products and tax revenue. Own price elasticities for bidi were highest in the poorest group (-0.4328) and lowest in the richest group (-0.0815). Cigarette own price elasticities were -0.832 in the poorest group and -0.2645 in the richest group. Leaf tobacco elasticities were highest in the poorest (-0.557) and middle (-0.4537) groups. Poorer group elasticities were the highest, indicating that poorer consumers are more price responsive. Elasticity estimates show positive distributional effects of uniform bidi and cigarette taxation on the poorest consumers, as their consumption is affected the most due to increases in taxation. Leaf tobacco also displayed moderate elasticities in poor and middle tertiles, suggesting that tax increases may result in a trade-off between consumption decline and revenue generation. A broad spectrum rise in tax rates across all products is critical for

  1. On linking an Earth system model to the equilibrium carbon representation of an economically optimizing land use model

    SciTech Connect

    Bond-Lamberty, Benjamin; Calvin, Katherine V.; Jones, Andrew D.; Mao, Jiafu; Patel, Pralit L.; Shi, Xiaoying; Thomson, Allison M.; Thornton, Peter E.; Zhou, Yuyu

    2014-01-01

    Human activities are significantly altering biogeochemical cycles at the global scale, posing a significant problem for earth system models (ESMs), which may incorporate static land-use change inputs but do not actively simulate policy or economic forces. One option to address this problem is a to couple an ESM with an economically oriented integrated assessment model. Here we have implemented and tested a coupling mechanism between the carbon cycles of an ESM (CLM) and an integrated assessment (GCAM) model, examining the best proxy variables to share between the models, and quantifying our ability to distinguish climate- and land-use-driven flux changes. CLM’s net primary production and heterotrophic respiration outputs were found to be the most robust proxy variables by which to manipulate GCAM’s assumptions of long-term ecosystem steady state carbon, with short-term forest production strongly correlated with long-term biomass changes in climate-change model runs. By leveraging the fact that carbon-cycle effects of anthropogenic land-use change are short-term and spatially limited relative to widely distributed climate effects, we were able to distinguish these effects successfully in the model coupling, passing only the latter to GCAM. By allowing climate effects from a full earth system model to dynamically modulate the economic and policy decisions of an integrated assessment model, this work provides a foundation for linking these models in a robust and flexible framework capable of examining two-way interactions between human and earth system processes.

  2. Basin Economic Allocation Model (BEAM): An economic model of water use developed for the Aral Sea Basin

    NASA Astrophysics Data System (ADS)

    Riegels, Niels; Kromann, Mikkel; Karup Pedersen, Jesper; Lindgaard-Jørgensen, Palle; Sokolov, Vadim; Sorokin, Anatoly

    2013-04-01

    The water resources of the Aral Sea basin are under increasing pressure, particularly from the conflict over whether hydropower or irrigation water use should take priority. The purpose of the BEAM model is to explore the impact of changes to water allocation and investments in water management infrastructure on the overall welfare of the Aral Sea basin. The BEAM model estimates welfare changes associated with changes to how water is allocated between the five countries in the basin (Kazakhstan, Kyrgyz Republic, Tajikistan, Turkmenistan and Uzbekistan; water use in Afghanistan is assumed to be fixed). Water is allocated according to economic optimization criteria; in other words, the BEAM model allocates water across time and space so that the economic welfare associated with water use is maximized. The model is programmed in GAMS. The model addresses the Aral Sea Basin as a whole - that is, the rivers Syr Darya, Amu Darya, Kashkadarya, and Zarafshan, as well as the Aral Sea. The model representation includes water resources, including 14 river sections, 6 terminal lakes, 28 reservoirs and 19 catchment runoff nodes, as well as land resources (i.e., irrigated croplands). The model covers 5 sectors: agriculture (crops: wheat, cotton, alfalfa, rice, fruit, vegetables and others), hydropower, nature, households and industry. The focus of the model is on welfare impacts associated with changes to water use in the agriculture and hydropower sectors. The model aims at addressing the following issues of relevance for economic management of water resources: • Physical efficiency (estimating how investments in irrigation efficiency affect economic welfare). • Economic efficiency (estimating how changes in how water is allocated affect welfare). • Equity (who will gain from changes in allocation of water from one sector to another and who will lose?). Stakeholders in the region have been involved in the development of the model, and about 10 national experts, including

  3. Calibrating and updating the Global Forest Products Model (GFPM version 2016 with BPMPD)

    Treesearch

    Joseph Buongiorno; Shushuai  Zhu

    2016-01-01

    The Global Forest Products Model (GFPM) is an economic model of global production, consumption, and trade of forest products. An earlier version of the model is described in Buongiorno et al. (2003). The GFPM 2016 has data and parameters to simulate changes of the forest sector from 2013 to 2030. Buongiorno and Zhu (2015) describe how to use the model for...

  4. Calibrating and Updating the Global Forest Products Model (GFPM version 2014 with BPMPD)

    Treesearch

    Joseph Buongiorno; Shushuai Zhu

    2014-01-01

    The Global Forest Products Model (GFPM) is an economic model of global production, consumption, and trade of forest products. An earlier version of the model is described in Buongiorno et al. (2003). The GFPM 2014 has data and parameters to simulate changes of the forest sector from 2010 to 2030. Buongiorno and Zhu (2014) describe how to use the model for simulation....

  5. Macro-economic models with non-zero dispersion

    NASA Astrophysics Data System (ADS)

    Aoki, Masanao

    2007-06-01

    Using two simple stochastic dynamic models, this paper demonstrates that the coe cient of variation of aggregate output, GDP, does not necessarily go to zero when the number of sectors or economic agents goes to infinity. This paper shows that this phenomenon, known as non-self averaging in physics, occurs in the two-parameter Poisson-Dirichlet models, and in certain balanced triangular urn models of growth. This implies that the standard microeconomic functions for aggregate outpu based on the representative agent models have little value, since these models do not provide us with better picture of the long-run behavior of the model. The paper also shows both models have a generalized Mittag-Le er density function, which has power-law tail.

  6. Economic inequality and mobility in kinetic models for social sciences

    NASA Astrophysics Data System (ADS)

    Letizia Bertotti, Maria; Modanese, Giovanni

    2016-10-01

    Statistical evaluations of the economic mobility of a society are more difficult than measurements of the income distribution, because they require to follow the evolution of the individuals' income for at least one or two generations. In micro-to-macro theoretical models of economic exchanges based on kinetic equations, the income distribution depends only on the asymptotic equilibrium solutions, while mobility estimates also involve the detailed structure of the transition probabilities of the model, and are thus an important tool for assessing its validity. Empirical data show a remarkably general negative correlation between economic inequality and mobility, whose explanation is still unclear. It is therefore particularly interesting to study this correlation in analytical models. In previous work we investigated the behavior of the Gini inequality index in kinetic models in dependence on several parameters which define the binary interactions and the taxation and redistribution processes: saving propensity, taxation rates gap, tax evasion rate, welfare means-testing etc. Here, we check the correlation of mobility with inequality by analyzing the mobility dependence from the same parameters. According to several numerical solutions, the correlation is confirmed to be negative.

  7. A comparison of economic evaluation models as applied to geothermal energy technology

    NASA Technical Reports Server (NTRS)

    Ziman, G. M.; Rosenberg, L. S.

    1983-01-01

    Several cost estimation and financial cash flow models have been applied to a series of geothermal case studies. In order to draw conclusions about relative performance and applicability of these models to geothermal projects, the consistency of results was assessed. The model outputs of principal interest in this study were net present value, internal rate of return, or levelized breakeven price. The models used were VENVAL, a venture analysis model; the Geothermal Probabilistic Cost Model (GPC Model); the Alternative Power Systems Economic Analysis Model (APSEAM); the Geothermal Loan Guarantee Cash Flow Model (GCFM); and the GEOCOST and GEOCITY geothermal models. The case studies to which the models were applied include a geothermal reservoir at Heber, CA; a geothermal eletric power plant to be located at the Heber site; an alcohol fuels production facility to be built at Raft River, ID; and a direct-use, district heating system in Susanville, CA.

  8. A comparison of economic evaluation models as applied to geothermal energy technology

    NASA Technical Reports Server (NTRS)

    Ziman, G. M.; Rosenberg, L. S.

    1983-01-01

    Several cost estimation and financial cash flow models have been applied to a series of geothermal case studies. In order to draw conclusions about relative performance and applicability of these models to geothermal projects, the consistency of results was assessed. The model outputs of principal interest in this study were net present value, internal rate of return, or levelized breakeven price. The models used were VENVAL, a venture analysis model; the Geothermal Probabilistic Cost Model (GPC Model); the Alternative Power Systems Economic Analysis Model (APSEAM); the Geothermal Loan Guarantee Cash Flow Model (GCFM); and the GEOCOST and GEOCITY geothermal models. The case studies to which the models were applied include a geothermal reservoir at Heber, CA; a geothermal eletric power plant to be located at the Heber site; an alcohol fuels production facility to be built at Raft River, ID; and a direct-use, district heating system in Susanville, CA.

  9. [Economic management of health crises affecting production animals in Europe].

    PubMed

    Vandeputte, S; Humblet, M F; Fecher-Bourgeois, F; Gosset, C; Albert, A; Vernaillen, F; Saegerman, C

    2011-12-01

    The importance of animal health crises has considerably increased over the last few years. When a crisis occurs, farmers can receive financial support through various public, private and mixed compensation schemes. Economic losses resulting from diseases may be direct and indirect. If a disease is covered by European Union regulations then countries have a legal obligation to partly compensate farmers for direct losses, either directly through the national budget, or through a specific fund. The European Veterinary Fund also co-finances these losses. Only a few countries provide compensation for indirect losses. The private insurance sector also provides protection against some direct and indirect losses but the risks covered are variable. To encourage farmers to subscribe to this kind of insurance, some public authorities provide subsidies to help pay the premium. Insurance companies do not generally cover the risks linked to contagious diseases, but some companies do extend cover to include this type of risk. Several alternatives, such as mutual funds, are available to improve risk coverage. There is a lack of harmonisation among the various compensation schemes of different countries. Public authorities cannot provide full compensation, but mutual funds and private insurance companies are alternatives that should be further investigated and their use should be extended to other countries. A classification of diseases would harmonise the situation at the European level.

  10. Economic value of tropical forest to coffee production

    PubMed Central

    Ricketts, Taylor H.; Daily, Gretchen C.; Ehrlich, Paul R.; Michener, Charles D.

    2004-01-01

    Can economic forces be harnessed for biodiversity conservation? The answer hinges on characterizing the value of nature, a tricky business from biophysical, socioeconomic, and ethical perspectives. Although the societal benefits of native ecosystems are clearly immense, they remain largely unquantified for all but a few services. Here, we estimate the value of tropical forest in supplying pollination services to agriculture. We focus on coffee because it is one of the world's most valuable export commodities and is grown in many of the world's most biodiverse regions. Using pollination experiments along replicated distance gradients, we found that forest-based pollinators increased coffee yields by 20% within ≈1 km of forest. Pollination also improved coffee quality near forest by reducing the frequency of “peaberries” (i.e., small misshapen seeds) by 27%. During 2000–2003, pollination services from two forest fragments (46 and 111 hectares) translated into ≈$60,000 (U.S.) per year for one Costa Rican farm. This value is commensurate with expected revenues from competing land uses and far exceeds current conservation incentive payments. Conservation investments in human-dominated landscapes can therefore yield double benefits: for biodiversity and agriculture. PMID:15306689

  11. FPL-PELPS : a price endogenous linear programming system for economic modeling, supplement to PELPS III, version 1.1.

    Treesearch

    Patricia K. Lebow; Henry Spelter; Peter J. Ince

    2003-01-01

    This report provides documentation and user information for FPL-PELPS, a personal computer price endogenous linear programming system for economic modeling. Originally developed to model the North American pulp and paper industry, FPL-PELPS follows its predecessors in allowing the modeling of any appropriate sector to predict consumption, production and capacity by...

  12. Energy/economic model analysis. Energy economic modeling system. Final report

    SciTech Connect

    Nesbitt, D.M.; Oman, D.B.

    1980-06-01

    The Decision Focus Incorporated (DFI) Energy-Economy Model used in this study is an integrating model designed in part to focus on two budget-related decisions. Specifically, the DFI model provides a robust but simple way of computing the benefits of successful RandD both in the aggregate and at the level of individual RandD projects.

  13. GEEF: a geothermal engineering and economic feasibility model. Description and user's manual

    SciTech Connect

    Not Available

    1982-09-01

    The model is designed to enable decision makers to compare the economics of geothermal projects with the economics of alternative energy systems at an early stage in the decision process. The geothermal engineering and economic feasibility computer model (GEEF) is written in FORTRAN IV language and can be run on a mainframe or a mini-computer system. An abbreviated version of the model is being developed for usage in conjunction with a programmable desk calculator. The GEEF model has two main segments, namely (i) the engineering design/cost segment and (ii) the economic analysis segment. In the engineering segment, the model determines the numbers of production and injection wells, heat exchanger design, operating parameters for the system, requirement of supplementary system (to augment the working fluid temperature if the resource temperature is not sufficiently high), and the fluid flow rates. The model can handle single stage systems as well as two stage cascaded systems in which the second stage may involve a space heating application after a process heat application in the first stage.

  14. Cardiac echo-lab productivity in times of economic austerity.

    PubMed

    Katsi, Vasiliki K; Vrachatis, Dimitrios A; Politi, Anastasia; Papageorgiou, Manto; Koumoulidis, Anastasios; Vlasseros, Ioannis; Vavuranakis, Manolis; Tousoulis, Dimitrios; Stefanadis, Christodoulos; Kallikazaros, Ioannis; Souliotis, Kyriakos

    2014-01-01

    The present study attempts to offer insight into the volume, cost, and productivity of the operation of a cardiac echocardiographic laboratory (echo-lab) in a major public hospital of Greece and thus to contribute, on a practical level, to the widening of knowledge in the strategic field of secondary and tertiary healthcare management. The conducted research includes the basic step of the deployment of a primary data registry in the echo-lab and unfolds in three levels, i.e. the variability measurement of the quantity and cost of medical services provided to different patient populations, the assessment of operating costs and the development of productivity indexes. The results show that the mean costs of provision do change among distinct patient populations. The most important, from a financial standpoint, population cluster appears to be the one corresponding to outpatients. Productivity indices presented in this analysis constitute an essential piece of information which the public healthcare system is currently largely lacking, and which, combined with the pricing and the diagnosis-related group coding system of hospitals, can be used to improve efficiency in the management of secondary and tertiary care.

  15. Production economics analysis of investment initiated to improve working environment.

    PubMed

    Abrahamsson, L

    2000-02-01

    This article describes the results of an evaluation of a new work place for ladle preparation at Swedish Steel in Luleå, Sweden. The company initiated a development project related to ladle service work, in order to come to grips with the difficult working environment and problems associated with absenteeism due to illness and occupational injuries. The evaluation was performed for the first three years after implementation of the project and it shows that the new work place considerably improved working conditions and increased both the quality and efficiency of production. The purpose of this article is also to discuss some methodological problems. The follow-up of the various changes in working environment and personnel statistics was fairly simple to carry out. But in terms of production effects, the company's in-house production follow-up system proved to be too unspecified and oversimplified. It was also difficult to decide which changes should count as effects of the new work place and to value these in monetary terms. The profitability calculation shows that an investment initiated to improve the working environment can yield good profitability.

  16. Assessing the production and economic benefits from preventing cows grazing on wet soils in New Zealand.

    PubMed

    Laurenson, Seth; Houlbrooke, David J; Beukes, Pierre C

    2016-10-01

    Intensive grazing by cattle on wet pasture can have a negative effect on soil physical quality and future pasture production. On a North Otago dairy farm in New Zealand, experimental plots were monitored for four years to assess whether preventing cow grazing of wet pastures during the milking season would improve soil structure and pasture production compared with unrestricted access to pastures. The DairyNZ Whole Farm Model was used to scale up results to a farm system level and ascertain the cost benefit of deferred grazing management. Soils under deferred grazing management had significantly higher total porosity, yet no significant improvement in macroporosity (values ranging between 0.112 and 0.146 m(3)  m(-3) ). Annual pasture production did not differ between the control and deferred grazing treatments, averaging 17.0 ± 3.8 and 17.9 ± 4.1 t DM ha(-1) year(-1) respectively (P > 0.05). Furthermore, whole farm modelling indicated that farm operating profit was reduced by NZ$1683 ha(-1) year(-1) (four-year average) under deferred grazing management. Deferring dairy cow grazing from wet Pallic soils in North Otago was effective in improving soil structure (measured as total soil porosity), yet did not lead to a significant increase in pasture production. Whole farm modelling indicated no economic benefit of removing cows from wet soils during the milking season. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  17. Boom and bust in continuous time evolving economic model

    NASA Astrophysics Data System (ADS)

    Mitchell, L.; Ackland, G. J.

    2009-08-01

    We show that a simple model of a spatially resolved evolving economic system, which has a steady state under simultaneous updating, shows stable oscillations in price when updated asynchronously. The oscillations arise from a gradual decline of the mean price due to competition among sellers competing for the same resource. This lowers profitability and hence population but is followed by a sharp rise as speculative sellers invade the large un-inhabited areas. This cycle then begins again.

  18. Assessing groundwater policy with coupled economic-groundwater hydrologic modeling

    NASA Astrophysics Data System (ADS)

    Mulligan, Kevin B.; Brown, Casey; Yang, Yi-Chen E.; Ahlfeld, David P.

    2014-03-01

    This study explores groundwater management policies and the effect of modeling assumptions on the projected performance of those policies. The study compares an optimal economic allocation for groundwater use subject to streamflow constraints, achieved by a central planner with perfect foresight, with a uniform tax on groundwater use and a uniform quota on groundwater use. The policies are compared with two modeling approaches, the Optimal Control Model (OCM) and the Multi-Agent System Simulation (MASS). The economic decision models are coupled with a physically based representation of the aquifer using a calibrated MODFLOW groundwater model. The results indicate that uniformly applied policies perform poorly when simulated with more realistic, heterogeneous, myopic, and self-interested agents. In particular, the effects of the physical heterogeneity of the basin and the agents undercut the perceived benefits of policy instruments assessed with simple, single-cell groundwater modeling. This study demonstrates the results of coupling realistic hydrogeology and human behavior models to assess groundwater management policies. The Republican River Basin, which overlies a portion of the Ogallala aquifer in the High Plains of the United States, is used as a case study for this analysis.

  19. Price elasticity of tobacco products among economic classes in India, 2011–2012

    PubMed Central

    Selvaraj, Sakthivel; Srivastava, Swati; Karan, Anup

    2015-01-01

    Objectives The objectives of this study are to: (1) examine the pattern of price elasticity of three major tobacco products (bidi, cigarette and leaf tobacco) by economic groups of population based on household monthly per capita consumption expenditure in India and (2) assess the effect of tax increases on tobacco consumption and revenue across expenditure groups. Setting Data from the 2011–2012 nationally representative Consumer Expenditure Survey from 101 662 Indian households were used. Participants Households which consumed any tobacco or alcohol product were retained in final models. Primary outcome measures The study draws theoretical frameworks from a model using the augmented utility function of consumer behaviour, with a two-stage two-equation system of unit values and budget shares. Primary outcome measures were price elasticity of demand for different tobacco products for three hierarchical economic groups of population and change in tax revenue due to changes in tax structure. We finally estimated price elasticity of demand for bidi, cigarette and leaf tobacco and effects of changes in their tax rates on demand for these tobacco products and tax revenue. Results Own price elasticities for bidi were highest in the poorest group (−0.4328) and lowest in the richest group (−0.0815). Cigarette own price elasticities were −0.832 in the poorest group and −0.2645 in the richest group. Leaf tobacco elasticities were highest in the poorest (−0.557) and middle (−0.4537) groups. Conclusions Poorer group elasticities were the highest, indicating that poorer consumers are more price responsive. Elasticity estimates show positive distributional effects of uniform bidi and cigarette taxation on the poorest consumers, as their consumption is affected the most due to increases in taxation. Leaf tobacco also displayed moderate elasticities in poor and middle tertiles, suggesting that tax increases may result in a trade-off between consumption decline and

  20. Distributed Perfusion Educational Model: A Shift in Perfusion Economic Realities

    PubMed Central

    Austin, Jon W.; Evans, Edward L.; Hoerr, Harry R.

    2005-01-01

    Abstract: In recent years, a steady decline in the number of perfusion education programs in the United States has been noted. At the same time, there has been a parallel decline in the number of students graduated from perfusion educational programs in the United States. Also, as noted by several authors, there has been an increase in demand for perfusion graduates. The decline in programs and graduates has also been noted in anesthesia and surgical residency programs. The shift is caused by a combination of economic and clinical factors. First, decreased reimbursement has led to reallocation of hospital resources. Second, the original enthusiasm for beating heart coronary artery bypass surgery was grossly overestimated and has led to further reallocation of hospital resources and denigration of cardiopulmonary bypass. This paper describes two models of perfusion education programs: serial perfusion education model (SPEM) and the distributed perfusion education model (DPEM). Arguments are presented that the SPEM has some serious limitations and challenges for long-term economic survival. The authors feel the DPEM along with dependence on tuition funding can survive the current clinical and economic conditions and allow the profession to adapt to changes in scope of practice. PMID:16524152

  1. Economic Dispatch for Microgrid Containing Electric Vehicles via Probabilistic Modelling

    SciTech Connect

    Yao, Yin; Gao, Wenzhong; Momoh, James; Muljadi, Eduard

    2015-10-06

    In this paper, an economic dispatch model with probabilistic modeling is developed for microgrid. Electric power supply in microgrid consists of conventional power plants and renewable energy power plants, such as wind and solar power plants. Due to the fluctuation of solar and wind plants' output, an empirical probabilistic model is developed to predict their hourly output. According to different characteristics of wind and solar plants, the parameters for probabilistic distribution are further adjusted individually for both power plants. On the other hand, with the growing trend of Plug-in Electric Vehicle (PHEV), an integrated microgrid system must also consider the impact of PHEVs. Not only the charging loads from PHEVs, but also the discharging output via Vehicle to Grid (V2G) method can greatly affect the economic dispatch for all the micro energy sources in microgrid. This paper presents an optimization method for economic dispatch in microgrid considering conventional, renewable power plants, and PHEVs. The simulation results reveal that PHEVs with V2G capability can be an indispensable supplement in modern microgrid.

  2. Impact of product mix and markets on the economic feasibility of hardwood thinning

    Treesearch

    John E. Baumgras; Chris B. LeDoux

    1989-01-01

    Results demonstrate how the economic feasibility of commercial hardwood thinning is impacted by tree diameter, product mix, and primary product markets. These results indicate that multiproduct harvesting can increase revenues by $0.01/ft³ to $0.32/ft³; and that small shifts in price levels or haul distance can postpone commercial thinning...

  3. Integrated Emergy and Economic Evaluation of Tea Production Chains in Anxi, China

    EPA Science Inventory

    Emergy and economic methods were used to evaluate and compare tea production systems in Anxi, China. Tea production was classified into three phases, i.e., the nursery, the plantation and tea processing, and each phase was evaluated. The results showed that the nursery subsystems...

  4. Economic and environmental effects of accelerated tariff liberalization in the forest products sector.

    Treesearch

    D.J. Brooks; J.A. Ferrante; J. Haverkamp; I. Bowles; W. Lange; D. Darr

    2001-01-01

    This study assesses the incremental economic and environmental impacts resulting from changes in the timing and scope of forest products tariff reductions as proposed in the Accelerated Tariff Liberalization (ATL) initiative in forest products. This initiative was proposed for agreement among member countries of the World Trade Organization. The analysis of...

  5. Integrated Emergy and Economic Evaluation of Tea Production Chains in Anxi, China

    EPA Science Inventory

    Emergy and economic methods were used to evaluate and compare tea production systems in Anxi, China. Tea production was classified into three phases, i.e., the nursery, the plantation and tea processing, and each phase was evaluated. The results showed that the nursery subsystems...

  6. The Contribution of Education to Economic Productivity. Schooling in a Technological Society.

    ERIC Educational Resources Information Center

    De Bevoise, Wynn

    According to traditional measures, the productivity of the American worker has declined. If education's contribution to economic productivity is to be imprortant in this decade, the measures need better definition. Technology has affected our perception of how much education is required to keep pace with growth. Those who believe there is a…

  7. The Historical Role of the Production Function in Economics and Business

    ERIC Educational Resources Information Center

    Gordon, David; Vaughan, Richard

    2011-01-01

    The production function explains a basic technological relationship between scarce resources, or inputs, and output. This paper offers a brief overview of the historical significance and operational role of the production function in business and economics. The origin and development of this function over time is initially explored. Several…

  8. Modeling Production Plant Forming Processes

    SciTech Connect

    Rhee, M; Becker, R; Couch, R; Li, M

    2004-09-22

    Engineering has simulation tools and experience in modeling forming processes. Y-12 personnel have expressed interest in validating our tools and experience against their manufacturing process activities such as rolling, casting, and forging etc. We have demonstrated numerical capabilities in a collaborative DOE/OIT project with ALCOA that is nearing successful completion. The goal was to use ALE3D to model Alcoa's slab rolling process in order to demonstrate a computational tool that would allow Alcoa to define a rolling schedule that would minimize the probability of ingot fracture, thus reducing waste and energy consumption. It is intended to lead to long-term collaboration with Y-12 and perhaps involvement with other components of the weapons production complex. Using simulations to aid in design of forming processes can: decrease time to production; reduce forming trials and associated expenses; and guide development of products with greater uniformity and less scrap.

  9. Techno-Economic Basis for Coproduct Manufacturing To Enable Hydrocarbon Fuel Production from Lignocellulosic Biomass

    SciTech Connect

    Biddy, Mary J.; Davis, Ryan; Humbird, David; Tao, Ling; Dowe, Nancy; Guarnieri, Michael T.; Linger, Jeffrey G.; Karp, Eric M.; Salvachua, Davinia; Vardon, Derek R.; Beckham, Gregg T.

    2016-06-06

    Biorefinery process development relies on techno-economic analysis (TEA) to identify primary cost drivers, prioritize research directions, and mitigate technical risk for scale-up through development of detailed process designs. Here, we conduct TEA of a model 2000 dry metric ton-per-day lignocellulosic biorefinery that employs a two-step pretreatment and enzymatic hydrolysis to produce biomass-derived sugars, followed by biological lipid production, lipid recovery, and catalytic hydrotreating to produce renewable diesel blendstock (RDB). On the basis of projected near-term technical feasibility of these steps, we predict that RDB could be produced at a minimum fuel selling price (MFSP) of USD $9.55/gasoline-gallon-equivalent (GGE), predicated on the need for improvements in the lipid productivity and yield beyond current benchmark performance. This cost is significant given the limitations in scale and high costs for aerobic cultivation of oleaginous microbes and subsequent lipid extraction/recovery. In light of this predicted cost, we developed an alternative pathway which demonstrates that RDB costs could be substantially reduced in the near term if upgradeable fractions of biomass, in this case hemicellulose-derived sugars, are diverted to coproducts of sufficient value and market size; here, we use succinic acid as an example coproduct. The coproduction model predicts an MFSP of USD $5.28/GGE when leaving conversion and yield parameters unchanged for the fuel production pathway, leading to a change in biorefinery RDB capacity from 24 to 15 MM GGE/year and 0.13 MM tons of succinic acid per year. Additional analysis demonstrates that beyond the near-term projections assumed in the models here, further reductions in the MFSP toward $2-3/GGE (which would be competitive with fossil-based hydrocarbon fuels) are possible with additional transformational improvements in the fuel and coproduct trains, especially in terms of carbon efficiency to both fuels and

  10. Golbal Economic and Environmental Impacts of Increased Bioenergy Production

    SciTech Connect

    Wallace Tyner

    2012-05-30

    The project had three main objectives: to build and incorporate an explicit biomass energy sector within the GTAP analytical framework and data base; to provide an analysis of the impact of renewable fuel standards and other policies in the U.S. and E.U, as well as alternative biofuel policies in other parts of the world, on changes in production, prices, consumption, trade and poverty; and to evaluate environmental impacts of alternative policies for bioenergy development. Progress and outputs related to each objective are reported.

  11. Modeling hard clinical end-point data in economic analyses.

    PubMed

    Kansal, Anuraag R; Zheng, Ying; Palencia, Roberto; Ruffolo, Antonio; Hass, Bastian; Sorensen, Sonja V

    2013-11-01

    The availability of hard clinical end-point data, such as that on cardiovascular (CV) events among patients with type 2 diabetes mellitus, is increasing, and as a result there is growing interest in using hard end-point data of this type in economic analyses. This study investigated published approaches for modeling hard end-points from clinical trials and evaluated their applicability in health economic models with different disease features. A review of cost-effectiveness models of interventions in clinically significant therapeutic areas (CV diseases, cancer, and chronic lower respiratory diseases) was conducted in PubMed and Embase using a defined search strategy. Only studies integrating hard end-point data from randomized clinical trials were considered. For each study included, clinical input characteristics and modeling approach were summarized and evaluated. A total of 33 articles (23 CV, eight cancer, two respiratory) were accepted for detailed analysis. Decision trees, Markov models, discrete event simulations, and hybrids were used. Event rates were incorporated either as constant rates, time-dependent risks, or risk equations based on patient characteristics. Risks dependent on time and/or patient characteristics were used where major event rates were >1%/year in models with fewer health states (<7). Models of infrequent events or with numerous health states generally preferred constant event rates. The detailed modeling information and terminology varied, sometimes requiring interpretation. Key considerations for cost-effectiveness models incorporating hard end-point data include the frequency and characteristics of the relevant clinical events and how the trial data is reported. When event risk is low, simplification of both the model structure and event rate modeling is recommended. When event risk is common, such as in high risk populations, more detailed modeling approaches, including individual simulations or explicitly time-dependent event rates

  12. Future Projections for Southern High Plains Agriculture Using Coupled Economic and Hydrologic Models and Climate Variability

    NASA Astrophysics Data System (ADS)

    Rainwater, K.; Tewari, R.; Willis, D.; Stovall, J.; Hayhoe, K.; Hernandez, A.; Mauget, S. A.; Leiker, G.; Johnson, J.

    2013-12-01

    The objective of the project was to evaluate the hypothesis that predicted climate change will affect the useful life of the Ogallala aquifer in the Southern High Plains (SHP) through its impact on the amount of irrigation withdrawals, and thus affect the yields and economic costs and net income. A ninety-year time frame has been considered, although the research team recognizes that long-term predictions of crop prices and selections are perhaps even more uncertain than long-term weather projections. Previous work by the research team recently demonstrated the development of regionally downscaled climate projections for the SHP. Quantitative projections of precipitation, potential evaporation, and temperature trends for the 90-yr duration were selected from a downscaled set of high-resolution (one-eighth degree) daily climate and hydrological simulations covering the entire Great Plains region, driven by the latest IPCC AR4 climate model outputs. These projections were used as input to the Ogallala Ag Tool software developed by the USDA-ARS to predict daily and seasonal values of those variables, which directly affect irrigation, at different locations in the study area. Results from the Ogallala Ag Tool were then used to drive future projected crop production functions for cotton, corn, wheat, and sorghum using the DSSAT crop model. These production functions were then included in an integrated economic-hydrologic modeling approach that coupled an economic optimization model with a groundwater hydrological model. The groundwater model was based on the Texas Water Development Board's Southern Ogallala Groundwater Availability Model, which has been recalibrated by the research team for previous applications. The coupling of the two models allowed better recognition of spatial heterogeneity across the SHP, such that irrigation water availability was better represented through the spatial variations in pumping demands and saturated thickness. With this hydrologic

  13. Techno-economic analysis of bioethanol production from lignocellulosic residues in Colombia: a process simulation approach.

    PubMed

    Quintero, Julián A; Moncada, Jonathan; Cardona, Carlos A

    2013-07-01

    In this study a techno-economic analysis of the production of bioethanol from four lignocellusic (Sugarcane bagasse, Coffee cut-stems, Rice Husk, and Empty Fruit Bunches) residues is presented for the Colombian case. The ethanol production was evaluated using Aspen Plus and Aspen Process Economic Analyzer carrying out the simulation and the economic evaluation, respectively. Simulations included the composition of lignocellulosic residues, which was determined experimentally. It was found that empty fruit bunches presents the highest ethanol yield from a dry basis point of view (313.83 L/t), while rice husk produced less ethanol (250.56 L/t). The ethanol production cost was assessed for the standalone ethanol plant and the ethanol plant coupled with a cogeneration system. Moreover, ethanol production cost using EFB was the lowest with (0.49 US$/L) and without (0.58 US$/L) cogeneration scheme. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. ENHANCED HYDROGEN ECONOMICS VIA COPRODUCTION OF FUELS AND CARBON PRODUCTS

    SciTech Connect

    Kennel, Elliot B; Bhagavatula, Abhijit; Dadyburjor, Dady; Dixit, Santhoshi; Garlapalli, Ravinder; Magean, Liviu; Mukkha, Mayuri; Olajide, Olufemi A; Stiller, Alfred H; Yurchick, Christopher L

    2011-03-31

    This Department of Energy National Energy Technology Laboratory sponsored research effort to develop environmentally cleaner projects as a spin-off of the FutureGen project, which seeks to reduce or eliminate emissions from plants that utilize coal for power or hydrogen production. New clean coal conversion processes were designed and tested for coproducing clean pitches and cokes used in the metals industry as well as a heavy crude oil. These new processes were based on direct liquefaction and pyrolysis techniques that liberate volatile liquids from coal without the need for high pressure or on-site gaseous hydrogen. As a result of the research, a commercial scale plant for the production of synthetic foundry coke has broken ground near Wise, Virginia under the auspices of Carbonite Inc. This plant will produce foundry coke by pyrolyzing a blend of steam coal feedstocks. A second plant is planned by Quantex Energy Inc (in Texas) which will use solvent extraction to coproduce a coke residue as well as crude oil. A third plant is being actively considered for Kingsport, Tennessee, pending a favorable resolution of regulatory issues.

  15. Petroleum production structures: economic resources for Louisiana sport divers

    SciTech Connect

    Roberts, K.J.; Thompson, M.E.

    1983-08-01

    The era of expanding petroleum production from marine waters began 12 miles off the Louisiana coast in 1947 with a joint operation. Since then, the expansion of drilling and production operations has continued until, in 1981, approximately 3,500 structures were located in the Gulf of Mexico. Of the total number of structures, federal and state waters off Louisiana contain 3,100. Scientific articles dealing with the role of structures in marine habitat and their relationship to sport fishing in the Gulf of Mexico increased over the decade. This newly publicized beneficial aspect of structures is particularly important to the marine fishery off Louisiana. The structures (to which Dugas et al. attribute 'nearly all of the offshore sport fishery') are called as platforms in their description: These platforms are supported by a prewelded framework of steel pipe. Structures in other areas of the country also attract marine life and sport fishermen. Catch rates by sport fishermen were two to three times higher near structures off California than near natural reefs. (Turner et al. 1969). This may be the result of the 'fish-concentrating' nature of structures.

  16. Economic assessments of potato production systems in Maine

    USDA-ARS?s Scientific Manuscript database

    Using an integrated enterprise and whole-farm budget model for a 324-ha medium-sized potato farm, the profitability of potatoes grown in combination with fifteen common potato rotation crops in Maine are evaluated. Enterprise budgets for all sixteen crops are calculated while a whole-farm budget syn...

  17. Using Weather Data and Climate Model Output in Economic Analyses of Climate Change

    SciTech Connect

    Auffhammer, M.; Hsiang, S. M.; Schlenker, W.; Sobel, A.

    2013-06-28

    Economists are increasingly using weather data and climate model output in analyses of the economic impacts of climate change. This article introduces a set of weather data sets and climate models that are frequently used, discusses the most common mistakes economists make in using these products, and identifies ways to avoid these pitfalls. We first provide an introduction to weather data, including a summary of the types of datasets available, and then discuss five common pitfalls that empirical researchers should be aware of when using historical weather data as explanatory variables in econometric applications. We then provide a brief overview of climate models and discuss two common and significant errors often made by economists when climate model output is used to simulate the future impacts of climate change on an economic outcome of interest.

  18. Can cognitive science create a cognitive economics?

    PubMed

    Chater, Nick

    2015-02-01

    Cognitive science can intersect with economics in at least three productive ways: by providing richer models of individual behaviour for use in economic analysis; by drawing from economic theory in order to model distributed cognition; and jointly to create more powerful 'rational' models of cognitive processes and social interaction. There is the prospect of moving from behavioural economics to a genuinely cognitive economics.

  19. An Economic Model of U.S. Airline Operating Expenses

    NASA Technical Reports Server (NTRS)

    Harris, Franklin D.

    2005-01-01

    This report presents a new economic model of operating expenses for 67 airlines. The model is based on data that the airlines reported to the United States Department of Transportation in 1999. The model incorporates expense-estimating equations that capture direct and indirect expenses of both passenger and cargo airlines. The variables and business factors included in the equations are detailed enough to calculate expenses at the flight equipment reporting level. Total operating expenses for a given airline are then obtained by summation over all aircraft operated by the airline. The model's accuracy is demonstrated by correlation with the DOT Form 41 data from which it was derived. Passenger airlines are more accurately modeled than cargo airlines. An appendix presents a concise summary of the expense estimating equations with explanatory notes. The equations include many operational and aircraft variables, which accommodate any changes that airline and aircraft manufacturers might make to lower expenses in the future. In 1999, total operating expenses of the 67 airlines included in this study amounted to slightly over $100.5 billion. The economic model reported herein estimates $109.3 billion.

  20. Production of biosolid fuels from municipal sewage sludge: Technical and economic optimisation.

    PubMed

    Wzorek, Małgorzata; Tańczuk, Mariusz

    2015-08-01

    The article presents the technical and economic analysis of the production of fuels from municipal sewage sludge. The analysis involved the production of two types of fuel compositions: sewage sludge with sawdust (PBT fuel) and sewage sludge with meat and bone meal (PBM fuel). The technology of the production line of these sewage fuels was proposed and analysed. The main objective of the study is to find the optimal production capacity. The optimisation analysis was performed for the adopted technical and economic parameters under Polish conditions. The objective function was set as a maximum of the net present value index and the optimisation procedure was carried out for the fuel production line input capacity from 0.5 to 3 t h(-1), using the search step 0.5 t h(-1). On the basis of technical and economic assumptions, economic efficiency indexes of the investment were determined for the case of optimal line productivity. The results of the optimisation analysis show that under appropriate conditions, such as prices of components and prices of produced fuels, the production of fuels from sewage sludge can be profitable. In the case of PBT fuel, calculated economic indexes show the best profitability for the capacity of a plant over 1.5 t h(-1) output, while production of PBM fuel is beneficial for a plant with the maximum of searched capacities: 3.0 t h(-1). Sensitivity analyses carried out during the investigation show that influence of both technical and economic assessments on the location of maximum of objective function (net present value) is significant. © The Author(s) 2015.

  1. Environmental and economic suitability of forest biomass-based bioenergy production in the Southern United States

    NASA Astrophysics Data System (ADS)

    Dwivedi, Puneet

    This study attempts to ascertain the environmental and economic suitability of utilizing forest biomass for cellulosic ethanol production in the Southern United States. The study is divided into six chapters. The first chapter details the background and defines the relevance of the study along with objectives. The second chapter reviews the existing literature to ascertain the present status of various existing conversion technologies. The third chapter assesses the net energy ratio and global warming impact of ethanol produced from slash pine (Pinus elliottii Engelm.) biomass. A life-cycle assessment was applied to achieve the task. The fourth chapter assesses the role of emerging bioenergy and voluntary carbon markets on the profitability of non-industrial private forest (NIPF) landowners by combining the Faustmann and Hartmann models. The fifth chapter assesses perceptions of four stakeholder groups (Non-Government Organization, Academics, Industries, and Government) on the use of forest biomass for bioenergy production in the Southern United States using the SWOT-AHP (Strength, Weakness, Opportunity, and Threat-Analytical Hierarchy Process) technique. Finally, overall conclusions are made in the sixth chapter. Results indicate that currently the production of cellulosic ethanol is limited as the production cost of cellulosic ethanol is higher than the production cost of ethanol derived from corn. However, it is expected that the production cost of cellulosic ethanol will come down in the future from its current level due to ongoing research efforts. The total global warming impact of E85 fuel (production and consumption) was found as 10.44 tons where as global warming impact of an equivalent amount of gasoline (production and consumption) was 21.45 tons. This suggests that the production and use of ethanol derived from slash pine biomass in the form of E85 fuel in an automobile saves about 51% of carbon emissions when compared to gasoline. The net energy ratio

  2. Economic Analysis of Hydrogen Production from Wind: Preprint

    SciTech Connect

    Levene, J. I.

    2005-05-01

    The purpose of this analysis is to determine the cost of using wind energy to produce hydrogen for use as a transportation fuel. This analysis assumes that a market exists for 50,000 kg of hydrogen per day produced from wind at the wind site; only production costs to the front gate are included, no delivery or dispensing costs are included. Three different scenarios are examined: near term, which represents 2005 currently available technology; mid term, which represents technological improvements and price reductions in the next 5-10 years; and long term, which is representative of the best technology gains and price reductions surmised by industry at this point, and represents the next 10-25 years.

  3. Medical costs and economic production losses due to injuries in the Netherlands.

    PubMed

    van Beeck, E F; van Roijen, L; Mackenbach, J P

    1997-06-01

    To support injury control, we assessed the direct medical costs and indirect costs of injuries in the Netherlands, making use of recent advances in health economics. We estimated the direct medical costs with the help of available data on health care utilization as a consequence of injuries. In our calculations of indirect costs, we used two alternative approaches. We used the traditional human-capital approach, which estimates the potential economic production losses caused by diseases or injuries. In addition, we applied the friction-costs method, which was recently developed as an attempt to measure the actual economic production losses to society. Injuries are an important source of medical costs and economic production losses. Almost two-thirds of the medical costs are the result of injuries among females (mainly domestic injuries of elderly women). On the contrary, independent of the method used, more than 80% of the indirect costs are the result of injuries among males (mainly caused by a high frequency of traffic injuries, occupational injuries, and sports injuries among young males). The application of the friction-costs method confirms the importance of injuries as a source of production losses in comparison with other diseases, showing that they belong to the main three causes of indirect costs to society. Estimates of the medical costs and both the potential and actual economic production losses to society clearly demonstrate that injuries should be a major concern for health policy makers and the medical profession.

  4. Economic analysis of municipal wastewater utilization for thermoelectric power production

    SciTech Connect

    Safari, I.; Walker, M.; Abbasian, J.; Arastoopour, H.; Hsieh, M-K.; Theregowda, R.; Dzombak, D.; Miller, D.

    2011-01-01

    The thermoelectric power industry in the U.S. uses a large amount of freshwater. The large water demand is increasingly a problem, especially for new power plant development, as availability of freshwater for new uses diminishes in the United States. Reusing non-traditional water sources, such as treated municipal wastewater, provides one option to mitigate freshwater usage in the thermoelectric power industry. The amount of freshwater withdrawal that can be displaced with non-traditional water sources at a particular location requires evaluation of the water management and treatment requirements, considering the quality and abundance of the non-traditional water sources. This paper presents the development of an integrated costing model to assess the impact of degraded water treatment, as well as the implications of increased tube scaling in the main condenser. The model developed herein is used to perform case studies of various treatment, condenser cleaning and condenser configurations to provide insight into the ramifications of degraded water use in the cooling loops of thermoelectric power plants. Further, this paper lays the groundwork for the integration of relationships between degraded water quality, scaling characteristics and volatile emission within a recirculating cooling loop model.

  5. Screening Cardiac Surgery Patients for MRSA: An Economic Computer Model

    PubMed Central

    Lee, Bruce Y.; Wiringa, Ann E.; Bailey, Rachel R.; Goyal, Vishal; Lewis, G. Jonathan; Tsui, Becky Y. K.; Smith, Kenneth J.; Muder, Robert R.

    2012-01-01

    Objective To estimate the economic value of preoperative methicillin-resistant Staphylococcus aureus (MRSA) screening and decolonization for cardiac surgery patients. Study Design Monte Carlo decision-analytic computer simulation model. Methods We developed a computer simulation model representing the decision of whether to perform preoperative MRSA screening and decolonizing those patients with a positive MRSA culture. Sensitivity analyses varied key input parameters including MRSA colonization prevalence, decolonization success rates, the number of surveillance sites, and screening/decolonization costs. Separate analyses estimated the incremental cost-effectiveness ratio (ICER) of the screening and decolonization strategy from the third-party payer and hospital perspectives. Results Even when MRSA colonization prevalence and decolonization success rate were as low as 1% and 25%, respectively, the ICER of implementing routine surveillance was well under $15,000 per quality-adjusted life-year from both the third-party payer and hospital perspectives. The surveillance strategy was economically dominant (less costly and more effective than no testing) for most scenarios explored. Conclusions Our results suggest that routine preoperative MRSA screening of cardiac surgery patients could provide substantial economic value to third-party payers and hospitals over a wide range of MRSA colonization prevalence levels, decolonization success rates, and surveillance costs. Healthcare administrators, infection control specialists, and surgeons can compare their local conditions with our study’s benchmarks to make decisions about whether to implement preoperative MRSA testing. Third-party payers may want to consider covering such a strategy. PMID:20645662

  6. A model to determine the economic viability of water fluoridation.

    PubMed

    Kroon, Jeroen; van Wyk, Philippus Johannes

    2012-01-01

    In view of concerns expressed by South African local authorities the aim of this study was to develop a model to determine whether water fluoridation is economically viable to reduce dental caries in South Africa. Microsoft Excel software was used to develop a model to determine economic viability of water fluoridation for 17 water providers from all nine South African provinces. Input variables for this model relate to chemical cost, labor cost, maintenance cost of infrastructure, opportunity cost, and capital depreciation. The following output variables were calculated to evaluate the cost of water fluoridation: per capita cost per year, cost-effectiveness and cost-benefit. In this model it is assumed that the introduction of community water fluoridation can reduce caries prevalence by an additional 15 percent and that the savings in cost of treatment will be equal to the average fee for a two surface restoration. Water providers included in the study serve 53.5 percent of the total population of South Africa. For all providers combined chemical cost contributes 64.5 percent to the total cost, per capita cost per year was $0.36, cost-effectiveness was calculated as $11.41 and cost-benefit of the implementation of water fluoridation was 0.34. This model confirmed that water fluoridation is an economically viable option to prevent dental caries in South African communities, as well as conclusions over the last 10 years that water fluoridation leads to significant cost savings and remains a cost-effective measure for reducing dental caries, even when the caries-preventive effectiveness is modest. © 2012 American Association of Public Health Dentistry.

  7. An analysis of prosthodontic research productivity: geographic, economic, and collaborative perspective.

    PubMed

    Thornton, Kathryn; Lee, Damian J; Yuan, Judy Chia-Chun; Knoernschild, Kent L; Campbell, Stephen D; Sukotjo, Cortino

    2012-01-01

    This study evaluated the quantity of prosthodontic literature produced globally by continent in three prosthodontic journals over a 10-year period, 1998-2008. Prosthodontic research productivity relative to economic status of countries and collaboration among countries grouped by economic status was assessed. Three peer-reviewed prosthodontic journals were used for the analysis of articles published in 1998, 2003, and 2008: The Journal of Prosthetic Dentistry, International Journal of Prosthodontics, and Journal of Prosthodontics. The country of every author listed for each included article was recorded. The number of articles published by each continent and each country was reported. Countries were grouped according to the World Bank economic classification system, and the number of articles published by each economic class was found. The majority of publications over the 10-year period were produced in Asia (Japan), Europe (Germany), and North America (USA). Productivity declined by 14.4% in high-income countries while it increased in upper middle-, lower middle-, and low-income countries. The majority of publications written by upper and lower middle- and low-income countries were independent works. Articles resulting from collaboration increased over time for all economic classes of countries. The origins of prosthodontic literature are becoming more geographically and economically diverse, with increased contributions from Africa, Asia, and South America, and middle- and low-income countries between 1998 and 2008. Collaboration between high-income countries and the other economic group countries increased over time. © 2011 by the American College of Prosthodontists.

  8. Economic and Technical Assessment of Wood Biomass Fuel Gasification for Industrial Gas Production

    SciTech Connect

    Anastasia M. Gribik; Ronald E. Mizia; Harry Gatley; Benjamin Phillips

    2007-09-01

    This project addresses both the technical and economic feasibility of replacing industrial gas in lime kilns with synthesis gas from the gasification of hog fuel. The technical assessment includes a materials evaluation, processing equipment needs, and suitability of the heat content of the synthesis gas as a replacement for industrial gas. The economic assessment includes estimations for capital, construction, operating, maintenance, and management costs for the reference plant. To perform these assessments, detailed models of the gasification and lime kiln processes were developed using Aspen Plus. The material and energy balance outputs from the Aspen Plus model were used as inputs to both the material and economic evaluations.

  9. Estimating productivity costs in health economic evaluations: a review of instruments and psychometric evidence.

    PubMed

    Tang, Kenneth

    2015-01-01

    Health economic evaluations (i.e. cost-effectiveness appraisal of an intervention) are useful aids for decision makers responsible for the allocation of scarce healthcare resources. The relevance of including health-related productivity costs (or benefits) in these evaluations is increasingly recognized and, as such, reliable and valid instruments to quantify productivity costs are needed. Over the years, a number of work productivity instruments have emerged in the literature, along with a growing body of psychometric evidence. The overall aim of this paper is to provide a review of available instruments with potential for estimating health-related productivity costs. This included the Health and Labor Questionnaire, Health and Work Performance Questionnaire, Health-Related Productivity Questionnaire Diary, Productivity and Disease Questionnaire, Quantity and Quality method, Stanford Presenteeism Scale 13, Valuation of Lost Productivity, Work and Health Interview, Work Limitations Questionnaire, Work Productivity and Activity Impairment Questionnaire, and Work Productivity Short Inventory. Critical discussions on the instruments' overall strengths and limitations, applicability for health economic evaluations, as well as the methodological quality of existing psychometric evidence were provided. Lastly, a set of reflective questions were proposed for users to consider when selecting an instrument for health economic evaluations.

  10. The question of Sudan: a hydro-economic optimization model for the Sudanese Blue Nile

    NASA Astrophysics Data System (ADS)

    Satti, S.; Zaitchik, B.; Siddiqui, S.

    2015-05-01

    The effects of development and the uncertainty of a changing climate in eastern Africa pose myriad challenges for water managers along the Blue Nile. Sudan's large irrigation potential, hydroelectric dams, and prime location within the basin mean that Sudan's water management decisions will have great social, economic and political implications for the region. At the same time, Sudan's water use options are constrained by tradeoffs between upstream irrigation developments and downstream hydropower facilities as well as by the country's commitments under existing or future transboundary water sharing agreements. Here, we present a model that can be applied to evaluate optimal allocation of surface water resources to irrigation and hydropower in the Sudanese portion of the Blue Nile. Hydrologic inputs are combined with agronomic and economic inputs to formulate an optimization model within the General Algebraic Modeling System (GAMS). A sensitivity analysis is performed by testing model response to a range of economic conditions and to changes in the volume and timing of hydrologic flows. Results indicate that changing hydroclimate inputs have the capacity to greatly influence the productivity of Sudan's water resource infrastructure. Results also show that the economically optimal volume of water consumption, and thus the importance of existing treaty constraints, is sensitive to the perceived value of agriculture relative to electricity as well as to changing hydrological conditions.

  11. Economic analysis of fuel ethanol production from winter hulled barley by the EDGE (Enhanced Dry Grind Enzymatic) process.

    PubMed

    Nghiem, Nhuan P; Ramírez, Edna C; McAloon, Andrew J; Yee, Winnie; Johnston, David B; Hicks, Kevin B

    2011-06-01

    A process and cost model was developed for fuel ethanol production from winter barley based on the EDGE (Enhanced Dry Grind Enzymatic) process. In this process, in addition to β-glucanases, which are added to reduce the viscosity of the mash, β-glucosidase is also added to completely hydrolyze the oligomers obtained during the hydrolysis of β-glucans to glucose. The model allows determination of capital costs, operating costs, and ethanol production cost for a plant producing 40 million gallons of denatured fuel ethanol annually. A sensitivity study was also performed to examine the effects of β-glucosidase and barley costs on the final ethanol production cost. The results of this study clearly demonstrate the economic benefit of adding β-glucosidase. Lower ethanol production cost was obtained compared to that obtained without β-glucosidase addition in all cases except one where highest β-glucosidase cost allowance and lowest barley cost were used.

  12. Clinical laboratory as an economic model for business performance analysis

    PubMed Central

    Buljanović, Vikica; Patajac, Hrvoje; Petrovečki, Mladen

    2011-01-01

    Aim To perform SWOT (strengths, weaknesses, opportunities, and threats) analysis of a clinical laboratory as an economic model that may be used to improve business performance of laboratories by removing weaknesses, minimizing threats, and using external opportunities and internal strengths. Methods Impact of possible threats to and weaknesses of the Clinical Laboratory at Našice General County Hospital business performance and use of strengths and opportunities to improve operating profit were simulated using models created on the basis of SWOT analysis results. The operating profit as a measure of profitability of the clinical laboratory was defined as total revenue minus total expenses and presented using a profit and loss account. Changes in the input parameters in the profit and loss account for 2008 were determined using opportunities and potential threats, and economic sensitivity analysis was made by using changes in the key parameters. The profit and loss account and economic sensitivity analysis were tools for quantifying the impact of changes in the revenues and expenses on the business operations of clinical laboratory. Results Results of simulation models showed that operational profit of €470 723 in 2008 could be reduced to only €21 542 if all possible threats became a reality and current weaknesses remained the same. Also, operational gain could be increased to €535 804 if laboratory strengths and opportunities were utilized. If both the opportunities and threats became a reality, the operational profit would decrease by €384 465. Conclusion The operational profit of the clinical laboratory could be significantly reduced if all threats became a reality and the current weaknesses remained the same. The operational profit could be increased by utilizing strengths and opportunities as much as possible. This type of modeling may be used to monitor business operations of any clinical laboratory and improve its financial situation by

  13. Clinical laboratory as an economic model for business performance analysis.

    PubMed

    Buljanović, Vikica; Patajac, Hrvoje; Petrovecki, Mladen

    2011-08-15

    To perform SWOT (strengths, weaknesses, opportunities, and threats) analysis of a clinical laboratory as an economic model that may be used to improve business performance of laboratories by removing weaknesses, minimizing threats, and using external opportunities and internal strengths. Impact of possible threats to and weaknesses of the Clinical Laboratory at Našice General County Hospital business performance and use of strengths and opportunities to improve operating profit were simulated using models created on the basis of SWOT analysis results. The operating profit as a measure of profitability of the clinical laboratory was defined as total revenue minus total expenses and presented using a profit and loss account. Changes in the input parameters in the profit and loss account for 2008 were determined using opportunities and potential threats, and economic sensitivity analysis was made by using changes in the key parameters. The profit and loss account and economic sensitivity analysis were tools for quantifying the impact of changes in the revenues and expenses on the business operations of clinical laboratory. Results of simulation models showed that operational profit of €470 723 in 2008 could be reduced to only €21 542 if all possible threats became a reality and current weaknesses remained the same. Also, operational gain could be increased to €535 804 if laboratory strengths and opportunities were utilized. If both the opportunities and threats became a reality, the operational profit would decrease by €384 465. The operational profit of the clinical laboratory could be significantly reduced if all threats became a reality and the current weaknesses remained the same. The operational profit could be increased by utilizing strengths and opportunities as much as possible. This type of modeling may be used to monitor business operations of any clinical laboratory and improve its financial situation by implementing changes in the next fiscal

  14. Incorporating incorporating economic models into seasonal pool conservation planning

    USGS Publications Warehouse

    Freeman, Robert C.; Bell, Kathleen P.; Calhoun, Aram J. K.; Loftin, Cyndy

    2012-01-01

    Massachusetts, New Jersey, Connecticut, and Maine have adopted regulatory zones around seasonal (vernal) pools to conserve terrestrial habitat for pool-breeding amphibians. Most amphibians require access to distinct seasonal habitats in both terrestrial and aquatic ecosystems because of their complex life histories. These habitat requirements make them particularly vulnerable to land uses that destroy habitat or limit connectivity (or permeability) among habitats. Regulatory efforts focusing on breeding pools without consideration of terrestrial habitat needs will not ensure the persistence of pool-breeding amphibians. We used GIS to combine a discrete-choice, parcel-scale economic model of land conversion with a landscape permeability model based on known habitat requirements of wood frogs (Lithobates sylvaticus) in Maine (USA) to examine permeability among habitat elements for alternative future scenarios. The economic model predicts future landscapes under different subdivision open space and vernal pool regulatory requirements. Our model showed that even “no build” permit zones extending 76 m (250 ft) outward from the pool edge were insufficient to assure permeability among required habitat elements. Furthermore, effectiveness of permit zones may be inconsistent due to interactions with other growth management policies, highlighting the need for local and state planning for the long-term persistence of pool-breeding amphibians in developing landscapes.

  15. Economic and environmental assessment of propionic acid production by fermentation using different renewable raw materials.

    PubMed

    Tufvesson, Pär; Ekman, Anna; Sardari, Roya R R; Engdahl, Kristina; Tufvesson, Linda

    2013-12-01

    Production of propionic acid by fermentation of glycerol as a renewable resource has been suggested as a means for developing an environmentally-friendly route for this commodity chemical. However, in order to quantify the environmental benefits, life cycle assessment of the production, including raw materials, fermentation, upstream and downstream processing is required. The economic viability of the process also needs to be analysed to make sure that any environmental savings can be realised. In this study an environmental and economic assessment from cradle-to-gate has been conducted. The study highlights the need for a highly efficient bioprocess in terms of product titre (more than 100g/L and productivity more than 2g/(L · h)) in order to be sustainable. The importance of the raw materials and energy production for operating the process to minimize emissions of greenhouse gases is also shown.

  16. Energy production, distribution, and pollution controls: Combining engineering and economic analysis to enhance efficiency and policy design

    NASA Astrophysics Data System (ADS)

    Perkis, David F.

    Three published articles are presented which focus on enhancing various aspects of the energy supply chain. While each paper adopts a different methodology, all three combine engineering data and/or techniques with economic analysis to improve efficiency or policy design within energy markets. The first paper combines a chemical engineering plant design model with an economic assessment of product enhancements within an ethanol production facility. While a new chemical process is shown to achieve greater ethanol yields, the animal feed by-products are denatured and decrease in value due to the degradation of a key nutritional amino acid. Overall, yield increases outweigh any costs, providing additional value to firms adopting this process. The second paper uses a mixed integer linear model to assess the optimal location of cellulosic ethanol production facilities within the state of Indiana. Desired locations with low costs are linked to regions with high yield corn growth, as these areas provide an abundance of corn stover, a by-product of corn and a cellulosic source of ethanol. The third paper implements experimental economic methods to assess the effectiveness of policies intended to control prices in emissions permit markets. When utilizing reserve permit auctions as an alternative to setting explicit maximum prices, prices are elevated beyond the theoretical predictions of the model within the conditions of the experiment. The most likely cause of higher prices is the negotiating power provided to sellers by grandfathering permits as evidenced by higher than expected welfare gains to sellers. Before presenting the articles, a discussion is introduced regarding the role of assumptions used by economists. For each article, a key assumption is highlighted and the consequences of making a different assumption are provided. Whether the consequences are large or small, the benefits of elucidating our models with assumptions based on real world behaviors are clearly

  17. Jobs and Economic Development Impacts from Small Wind: JEDI Model in the Works (Presentation)

    SciTech Connect

    Tegen, S.

    2012-06-01

    This presentation covers the National Renewable Energy Laboratory's role in economic impact analysis for wind power Jobs and Economic Development Impacts (JEDI) models, JEDI results, small wind JEDI specifics, and a request for information to complete the model.

  18. Modeling Joint Climate and Bioenergy Policies: Challenges of integrating economic and environmental data. (Invited)

    NASA Astrophysics Data System (ADS)

    Hellwinckel, C. M.; West, T. O.; de La Torre Ugarte, D.; Perlack, R.

    2010-12-01

    In the coming decades agriculture will be asked to play a significant role in reducing carbon emissions and reducing our use of foreign oil. The Renewable Fuels Standard combined with possible climate legislation will alter the economic landscape effecting agricultural land use decisions. The joint implementation of these two policies could potentially work against one another. We have integrated biogeophysical data into the POLYSYS economic model to analyze the effects of climate change and bioenergy legislation upon regional land-use change, soil carbon, carbon emissions, biofuel production, and agricultural income. The purpose of the analysis was to use the integrated model to identify carbon and bioenergy policies that could act synergistically to meet Renewable Fuel Standard goals, reduce net emissions of carbon, and increase agricultural incomes. The heterogeneous nature of soils, crop yields, and management practices presented challenges to the modeling process. Regional variation in physical data can significantly affect economic land use decisions and patterns. For this reason, we disaggregated the economic component of the model to the county level, with sub-county soils and land-use data informing the county level decisions. Modeling carbon offset dynamics presented unique challenges, as the physical responses of local soils impact the economic incentives offered, and conversely, the resulting land-use changes impact characteristics of local soils. Additionally, using data from different resolution levels led to questions of appropriate scale of analysis. This presentation will describe the integrated model, present some significant results from our analysis, and discuss appropriate steps forward given what we learned.

  19. Techno-economic evaluation of a two-step biological process for hydrogen production.

    PubMed

    Ljunggren, Mattias; Zacchi, Guido

    2010-01-01

    An integrated biological process for the production of hydrogen based on thermophilic and photo-heterotrophic fermentation was evaluated from a technical and economic standpoint. Besides the two fermentation steps the process also includes pretreatment of the raw material (potato steam peels) and purification of hydrogen using amine absorption. The study aimed neither at determining the absolute cost of biohydrogen nor at an economic optimization of the production process, but rather at studying the effects of different parameters on the production costs of biohydrogen as a guideline for future improvements. The effect of the key parameters, hydrogen productivity and yield and substrate concentration in the two fermentations on the cost of the hydrogen produced was studied. The selection of the process conditions was based mainly on laboratory data. The process was simulated by use of the software Aspen Plus and the capital costs were estimated using the program Aspen Icarus Process Evaluator. The study shows that the photo-fermentation is the main contributor to the hydrogen production cost mainly because of the cost of plastic tubing, for the photo-fermentors, which represents 40.5% of the hydrogen production cost. The costs of the capital investment and chemicals were also notable contributors to the hydrogen production cost. Major economic improvements could be achieved by increasing the productivity of the two fermentation steps on a medium-term to long-term scale.

  20. Unification and mechanistic detail as drivers of model construction: models of networks in economics and sociology.

    PubMed

    Kuorikoski, Jaakko; Marchionni, Caterina

    2014-12-01

    We examine the diversity of strategies of modelling networks in (micro) economics and (analytical) sociology. Field-specific conceptions of what explaining (with) networks amounts to or systematic preference for certain kinds of explanatory factors are not sufficient to account for differences in modelling methodologies. We argue that network models in both sociology and economics are abstract models of network mechanisms and that differences in their modelling strategies derive to a large extent from field-specific conceptions of the way in which a good model should be a general one. Whereas the economics models aim at unification, the sociological models aim at a set of mechanism schemas that are extrapolatable to the extent that the underlying psychological mechanisms are general. These conceptions of generality induce specific biases in mechanistic explanation and are related to different views of when knowledge from different fields should be seen as relevant.

  1. Methanol production with elemental phosphorus byproduct gas: technical and economic feasibility

    SciTech Connect

    Lyke, S.E.; Moore, R.H.

    1981-01-01

    The technical and economic feasibility of using a typical, elemental, phosphorus byproduct gas stream in methanol production is assessed. The purpose of the study is to explore the potential of a substitute for natural gas. The first part of the study establishes economic tradeoffs between several alternative methods of supplying the hydrogen which is needed in the methanol synthesis process to react with CO from the off gas. The preferred alternative is the Battelle Process, which uses natural gas in combination with the off gas in an economically sized methanol plant. The second part of the study presents a preliminary basic design of a plant to (1) clean and compress the off gas, (2) return recovered phosphorus to the phosphorus plant, and (3) produce methanol by the Battelle Process. Use of elemental phosphorus byproduct gas in methanol production appears to be technically feasible. The Battelle Process shows a definite but relatively small economic advantage over conventional methanol manufacture based on natural gas alone. The process would be economically feasible only where natural gas supply and methanol market conditions at a phosphorus plant are not significantly less favorable than at competing methanol plants. If off-gas streams from two or more phosphorus plants could be combined, production of methanol using only offgas might also be economically feasible. The North American methanol market, however, does not seem likely to require another new methanol project until after 1990. The off-gas cleanup, compression, and phosphorus-recovery system could be used to produce a CO-rich stream that could be economically attractive for production of several other chemicals besides methanol.

  2. Partial differential equation models in the socio-economic sciences.

    PubMed

    Burger, Martin; Caffarelli, Luis; Markowich, Peter A

    2014-11-13

    Mathematical models based on partial differential equations (PDEs) have become an integral part of quantitative analysis in most branches of science and engineering, recently expanding also towards biomedicine and socio-economic sciences. The application of PDEs in the latter is a promising field, but widely quite open and leading to a variety of novel mathematical challenges. In this introductory article of the Theme Issue, we will provide an overview of the field and its recent boosting topics. Moreover, we will put the contributions to the Theme Issue in an appropriate perspective.

  3. Partial differential equation models in the socio-economic sciences

    PubMed Central

    Burger, Martin; Caffarelli, Luis; Markowich, Peter A.

    2014-01-01

    Mathematical models based on partial differential equations (PDEs) have become an integral part of quantitative analysis in most branches of science and engineering, recently expanding also towards biomedicine and socio-economic sciences. The application of PDEs in the latter is a promising field, but widely quite open and leading to a variety of novel mathematical challenges. In this introductory article of the Theme Issue, we will provide an overview of the field and its recent boosting topics. Moreover, we will put the contributions to the Theme Issue in an appropriate perspective. PMID:25288814

  4. Methodology and basic algorithms of the Livermore Economic Modeling System

    SciTech Connect

    Bell, R.B.

    1981-03-17

    The methodology and the basic pricing algorithms used in the Livermore Economic Modeling System (EMS) are described. The report explains the derivations of the EMS equations in detail; however, it could also serve as a general introduction to the modeling system. A brief but comprehensive explanation of what EMS is and does, and how it does it is presented. The second part examines the basic pricing algorithms currently implemented in EMS. Each algorithm's function is analyzed and a detailed derivation of the actual mathematical expressions used to implement the algorithm is presented. EMS is an evolving modeling system; improvements in existing algorithms are constantly under development and new submodels are being introduced. A snapshot of the standard version of EMS is provided and areas currently under study and development are considered briefly.

  5. Toward a synthetic economic systems modeling tool for sustainable exploitation of ecosystems.

    PubMed

    Richardson, Colin; Courvisanos, Jerry; Crawford, John W

    2011-02-01

    Environmental resources that underpin the basic human needs of water, energy, and food are predicted to become in such short supply by 2050 that global security and the well-being of millions will be under threat. These natural commodities have been allowed to reach crisis levels of supply because of a failure of economic systems to sustain them. This is largely because there have been no means of integrating their exploitation into any economic model that effectively addresses ecological systemic failures in a way that provides an integrated ecological-economic tool that can monitor and evaluate market and policy targets. We review the reasons for this and recent attempts to address the problem while identifying outstanding issues. The key elements of a policy-oriented economic model that integrates ecosystem processes are described and form the basis of a proposed new synthesis approach. The approach is illustrated by an indicative case study that develops a simple model for rainfed and irrigated food production in the Murray-Darling basin of southeastern Australia.

  6. Economic modelling of grazing management against gastrointestinal nematodes in dairy cattle.

    PubMed

    van der Voort, M; Van Meensel, J; Lauwers, L; de Haan, M H A; Evers, A G; Van Huylenbroeck, G; Charlier, J

    2017-03-15

    Grazing management (GM) interventions, such as reducing the grazing time or mowing pasture before grazing, have been proposed to limit the exposure to gastrointestinal (GI) nematode infections in grazed livestock. However, the farm-level economic effects of these interventions have not yet been assessed. In this paper, the economic effects of three GM interventions in adult dairy cattle were modelled for a set of Flemish farms: later turnout on pasture (GM1), earlier housing near the end of the grazing season (GM2), and reducing the daily grazing time (GM3). Farm accountancy data were linked to Ostertagia ostertagi bulk tank milk ELISA results and GM data for 137 farms. The economic effects of the GM interventions were investigated through a combination of efficiency analysis and a whole-farm simulation model. Modelling of GM1, GM2 and GM3 resulted in a marginal economic effect of € 8.36, € -9.05 and € -53.37 per cow per year, respectively. The results suggest that the dairy farms can improve their economic performance by postponing the turnout date, but that advancing the housing date or reducing daily grazing time mostly leads to a lower net economic farm performance. Overall, the GM interventions resulted in a higher technical efficiency and milk production but these benefits were offset by increased feed costs as a result of higher maintenance and cultivation costs. Because the results differed highly between farms, GM interventions need to be evaluated at the individual level for appropriate decision support. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Economics of electricity production and distribution in rural areas of Nepal

    SciTech Connect

    Rijal, K.; Bansal, N.K.; Grover, P.D. )

    1990-01-01

    This paper aims at providing the comparative economics from a national perspective (economic analysis) and a users perspective (financial analysis) of low capacity (5-15 KW) electrical add-on systems and medium capacity (25-50 KW) electrical systems to provide electrical energy from various energy sources at three villages of Nepal, each from a different physiographic zone. In general, the increasing economic price of traditional energies coupled with deforestation in rural areas of developing countries and the increasing need for foreign exchange for import of fossil fuels, favors the judicial exploitation of renewable energy for electricity generation. The load factor is one of the most important factors that dictate the economic and financial supply price of electricity production and distribution. It is recommended that a detailed site-specific electricity demand analysis be carried out with appropriate end-use planning for decentralized rural electrification schemes.

  8. Measuring the intangibles: a metrics for the economic complexity of countries and products.

    PubMed

    Cristelli, Matthieu; Gabrielli, Andrea; Tacchella, Andrea; Caldarelli, Guido; Pietronero, Luciano

    2013-01-01

    We investigate a recent methodology we have proposed to extract valuable information on the competitiveness of countries and complexity of products from trade data. Standard economic theories predict a high level of specialization of countries in specific industrial sectors. However, a direct analysis of the official databases of exported products by all countries shows that the actual situation is very different. Countries commonly considered as developed ones are extremely diversified, exporting a large variety of products from very simple to very complex. At the same time countries generally considered as less developed export only the products also exported by the majority of countries. This situation calls for the introduction of a non-monetary and non-income-based measure for country economy complexity which uncovers the hidden potential for development and growth. The statistical approach we present here consists of coupled non-linear maps relating the competitiveness/fitness of countries to the complexity of their products. The fixed point of this transformation defines a metrics for the fitness of countries and the complexity of products. We argue that the key point to properly extract the economic information is the non-linearity of the map which is necessary to bound the complexity of products by the fitness of the less competitive countries exporting them. We present a detailed comparison of the results of this approach directly with those of the Method of Reflections by Hidalgo and Hausmann, showing the better performance of our method and a more solid economic, scientific and consistent foundation.

  9. A Predictive Model for the Marketing of Home Economics.

    ERIC Educational Resources Information Center

    Callahan, Kathryn A.

    1993-01-01

    Responses from 574 of 827 students in introductory home economics classes identified positive influences in selecting home economics as a major: friends, high school home economics teachers, and home economics faculty. Negative influences were family, other high school teachers, radio advertisements, and campus recruitment. (SK)

  10. Economic Pressure in African American Families: A Replication and Extension of the Family Stress Model.

    ERIC Educational Resources Information Center

    Conger, Rand D.; Wallace, Lora Ebert; Sun, Yumei; Simons, Ronald L.; McLoyd, Vonnie C.; Brody, Gene H.

    2002-01-01

    Evaluated applicability of family stress model of economic hardship for understanding economic influences on child development among African American families with a 10- or 11-year-old child. Found that economic hardship positively related to economic pressure in families, and to emotional distress of caregivers, which in turn damaged the…

  11. PRODUCTION AND ECONOMIC OPTIMIZATION OF DIETARY PROTEIN AND CARBOHYDRATE IN THE CULTURE OF JUVENILE SEA URCHIN Lytechinus variegatus.

    PubMed

    Heflin, Laura E; Makowsky, Robert; Taylor, J Christopher; Williams, Michael B; Lawrence, Addison L; Watts, Stephen A

    2016-10-01

    Juvenile Lytechinus variegatus (ca. 3.95± 0.54 g) were fed one of 10 formulated diets with different protein (ranging from 11- 43%) and carbohydrate (12 or 18%; brackets determined from previous studies) levels. Urchins (n= 16 per treatment) were fed a daily sub-satiation ration equivalent to 2.0% of average body weight for 10 weeks. Our objective was (1) to create predictive models of growth, production and efficiency outcomes and (2) to generate economic analysis models in relation to these dietary outcomes for juvenile L. variegatus held in culture. At dietary protein levels below ca. 30%, models for most growth and production outcomes predicted increased rates of growth and production among urchins fed diets containing 18% dietary carbohydrate levels as compared to urchins fed diets containing 12% dietary carbohydrate. For most outcomes, growth and production was predicted to increase with increasing level of dietary protein up to ca. 30%, after which, no further increase in growth and production were predicted. Likewise, dry matter production efficiency was predicted to increase with increasing protein level up to ca. 30%, with urchins fed diets with 18% carbohydrate exhibiting greater efficiency than those fed diets with 12% carbohydrate. The energetic cost of dry matter production was optimal at protein levels less than those required for maximal weight gain and gonad production, suggesting an increased energetic cost (decreased energy efficiency) is required to increase gonad production relative to somatic growth. Economic analysis models predict when cost of feed ingredients are low, the lowest cost per gram of wet weight gain will occur at 18% dietary carbohydrate and ca. 25- 30% dietary protein. In contrast, lowest cost per gram of wet weight gain will occur at 12% dietary carbohydrate and ca. 35- 40% dietary protein when feed ingredient costs are high or average. For both 18 and 12% levels of dietary carbohydrate, cost per gram of wet weight gain is

  12. Automated Decisional Model for Optimum Economic Order Quantity Determination Using Price Regressive Rates

    NASA Astrophysics Data System (ADS)

    Roşu, M. M.; Tarbă, C. I.; Neagu, C.

    2016-11-01

    The current models for inventory management are complementary, but together they offer a large pallet of elements for solving complex problems of companies when wanting to establish the optimum economic order quantity for unfinished products, row of materials, goods etc. The main objective of this paper is to elaborate an automated decisional model for the calculus of the economic order quantity taking into account the price regressive rates for the total order quantity. This model has two main objectives: first, to determine the periodicity when to be done the order n or the quantity order q; second, to determine the levels of stock: lighting control, security stock etc. In this way we can provide the answer to two fundamental questions: How much must be ordered? When to Order? In the current practice, the business relationships with its suppliers are based on regressive rates for price. This means that suppliers may grant discounts, from a certain level of quantities ordered. Thus, the unit price of the products is a variable which depends on the order size. So, the most important element for choosing the optimum for the economic order quantity is the total cost for ordering and this cost depends on the following elements: the medium price per units, the stock cost, the ordering cost etc.

  13. An Adaptive Regional Input-Output Model and its Application to the Assessment of the Economic Cost of Katrina

    NASA Astrophysics Data System (ADS)

    Hallegatte, S.

    2006-12-01

    Recent events, especially natural disasters, have raised concerns about the response of local economies to large exogenous shocks. Clearly, our ability to assess the total economic costs of large-scale events like the Katrina's landfall is very poor, and numerous questions needs to be investigated. Among them, the taking into account of complex interactions within the economic system --- between economic sectors or regions --- is the topic of intense research. Several studies have approached these issues using Input-Output models, which are powerful tools to assess how a shock, on one or several sectors, propagate into the economy through intermediate consumption and demand. These models, however, have two main short-comings. First, since they do not take into account productive capacity, they cannot assess the consequence of a shock on the supply-side. Second, they do not allow for flexibility in the economic system in that producers and consumers cannot respond to a lack in input. The presentation will describe an adaptive regional input-output model, which aims at answering the previous concerns through the introduction of an hybrid modelling methodology. This model takes into account economic propagations through both intermediate demands and production shortages, and also represents the response of economic agents facing production shortages. An application of this model to the evaluation of the economic cost of Katrina will be demonstrated, highlighting both modelling and data issues. Also, beyond a simple "best-guess" assessment, systematic sensitivity analyses will be presented, allowing for an evaluation of the accuracy one can expect from such a model.

  14. Environmental, economic and social impact of aviation biofuel production in Brazil.

    PubMed

    Cremonez, Paulo André; Feroldi, Michael; de Jesus de Oliveira, Carlos; Teleken, Joel Gustavo; Alves, Helton José; Sampaio, Silvio Cézar

    2015-03-25

    The Brazilian aviation industry is currently developing biofuel technologies that can maintain the operational and energy demands of the sector, while reducing the dependence on fossil fuels (mainly kerosene) and greenhouse gas emissions. The aim of the current research was to identify the major environmental, economic and social impacts arising from the production of aviation biofuels in Brazil. Despite the great potential of these fuels, there is a significant need for improved routes of production and specifically for lower production costs of these materials. In addition, the productive chains of raw materials for obtaining these bioenergetics can be linked to environmental impacts by NOx emissions, extensive use of agricultural land, loss of wildlife and intensive water use, as well as economic, social and political impacts.

  15. Environmental and economic aspects of hydrogen production and utilization in fuel cell vehicles

    NASA Astrophysics Data System (ADS)

    Granovskii, Mikhail; Dincer, Ibrahim; Rosen, Marc A.

    A smooth transition from gasoline-powered internal combustion engine vehicles to ecologically clean hydrogen fuel cell vehicles depends on the process used for hydrogen production. Three technologies for hydrogen production are considered here: traditional hydrogen production via natural gas reforming, and the use of two renewable technologies (wind and solar electricity generation) to produce hydrogen via water electrolysis. It is shown that a decrease of environmental impact (air pollution and greenhouse gas emissions) as a result of hydrogen implementation as a fuel is accompanied by a decline in the economic efficiency (as measured by capital investments effectiveness). A mathematical procedure is proposed to obtain numerical estimates of environmental and economic criteria interactions in the form of sustainability indexes. On the basis of the obtained sustainability indexes, it is concluded that hydrogen production from wind energy via electrolysis is more advantageous for mitigating greenhouse gas emissions and traditional natural gas reforming is more favorable for reducing air pollution.

  16. Techno-economic assessment of catalytic gasification of biomass powders for methanol production.

    PubMed

    Carvalho, Lara; Furusjö, Erik; Kirtania, Kawnish; Wetterlund, Elisabeth; Lundgren, Joakim; Anheden, Marie; Wolf, Jens

    2017-08-01

    This study evaluated the techno-economic performance and potential benefits of methanol production through catalytic gasification of forest residues and lignin. The results showed that while catalytic gasification enables increased cold gas efficiencies and methanol yields compared to non-catalytic gasification, the additional pre-treatment energy and loss of electricity production result in small or no system efficiency improvements. The resulting required methanol selling prices (90-130€/MWh) are comparable with production costs for other biofuels. It is concluded that catalytic gasification of forest residues can be an attractive option as it provides operational advantages at production costs comparable to non-catalytic gasification. The addition of lignin would require lignin costs below 25€/MWh to be economically beneficial. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Modeling perceptions of climatic risk in crop production.

    PubMed

    Reinmuth, Evelyn; Parker, Phillip; Aurbacher, Joachim; Högy, Petra; Dabbert, Stephan

    2017-01-01

    In agricultural production, land-use decisions are components of economic planning that result in the strategic allocation of fields. Climate variability represents an uncertainty factor in crop production. Considering yield impact, climatic influence is perceived during and evaluated at the end of crop production cycles. In practice, this information is then incorporated into planning for the upcoming season. This process contributes to attitudes toward climate-induced risk in crop production. In the literature, however, the subjective valuation of risk is modeled as a risk attitude toward variations in (monetary) outcomes. Consequently, climatic influence may be obscured by political and market influences so that risk perceptions during the production process are neglected. We present a utility concept that allows the inclusion of annual risk scores based on mid-season risk perceptions that are incorporated into field-planning decisions. This approach is exemplified and implemented for winter wheat production in the Kraichgau, a region in Southwest Germany, using the integrated bio-economic simulation model FarmActor and empirical data from the region. Survey results indicate that a profitability threshold for this crop, the level of "still-good yield" (sgy), is 69 dt ha-1 (regional mean Kraichgau sample) for a given season. This threshold governs the monitoring process and risk estimators. We tested the modeled estimators against simulation results using ten projected future weather time series for winter wheat production. The mid-season estimators generally proved to be effective. This approach can be used to improve the modeling of planning decisions by providing a more comprehensive evaluation of field-crop response to climatic changes from an economic risk point of view. The methodology further provides economic insight in an agrometeorological context where prices for crops or inputs are lacking, but farmer attitudes toward risk should still be included in

  18. Modeling perceptions of climatic risk in crop production

    PubMed Central

    Parker, Phillip; Aurbacher, Joachim; Högy, Petra; Dabbert, Stephan

    2017-01-01

    In agricultural production, land-use decisions are components of economic planning that result in the strategic allocation of fields. Climate variability represents an uncertainty factor in crop production. Considering yield impact, climatic influence is perceived during and evaluated at the end of crop production cycles. In practice, this information is then incorporated into planning for the upcoming season. This process contributes to attitudes toward climate-induced risk in crop production. In the literature, however, the subjective valuation of risk is modeled as a risk attitude toward variations in (monetary) outcomes. Consequently, climatic influence may be obscured by political and market influences so that risk perceptions during the production process are neglected. We present a utility concept that allows the inclusion of annual risk scores based on mid-season risk perceptions that are incorporated into field-planning decisions. This approach is exemplified and implemented for winter wheat production in the Kraichgau, a region in Southwest Germany, using the integrated bio-economic simulation model FarmActor and empirical data from the region. Survey results indicate that a profitability threshold for this crop, the level of “still-good yield” (sgy), is 69 dt ha-1 (regional mean Kraichgau sample) for a given season. This threshold governs the monitoring process and risk estimators. We tested the modeled estimators against simulation results using ten projected future weather time series for winter wheat production. The mid-season estimators generally proved to be effective. This approach can be used to improve the modeling of planning decisions by providing a more comprehensive evaluation of field-crop response to climatic changes from an economic risk point of view. The methodology further provides economic insight in an agrometeorological context where prices for crops or inputs are lacking, but farmer attitudes toward risk should still be included

  19. HIGH-TEMPERATURE ELECTROLYSIS FOR LARGE-SCALE HYDROGEN AND SYNGAS PRODUCTION FROM NUCLEAR ENERGY – SYSTEM SIMULATION AND ECONOMICS

    SciTech Connect

    J. E. O'Brien; M. G. McKellar; E. A. Harvego; C. M. Stoots

    2009-05-01

    A research and development program is under way at the Idaho National Laboratory (INL) to assess the technological and scale-up issues associated with the implementation of solid-oxide electrolysis cell technology for efficient high-temperature hydrogen production from steam. This work is supported by the US Department of Energy, Office of Nuclear Energy, under the Nuclear Hydrogen Initiative. This paper will provide an overview of large-scale system modeling results and economic analyses that have been completed to date. System analysis results have been obtained using the commercial code UniSim, augmented with a custom high-temperature electrolyzer module. Economic analysis results were based on the DOE H2A analysis methodology. The process flow diagrams for the system simulations include an advanced nuclear reactor as a source of high-temperature process heat, a power cycle and a coupled steam electrolysis loop. Several reactor types and power cycles have been considered, over a range of reactor outlet temperatures. Pure steam electrolysis for hydrogen production as well as coelectrolysis for syngas production from steam/carbon dioxide mixtures have both been considered. In addition, the feasibility of coupling the high-temperature electrolysis process to biomass and coal-based synthetic fuels production has been considered. These simulations demonstrate that the addition of supplementary nuclear hydrogen to synthetic fuels production from any carbon source minimizes emissions of carbon dioxide during the production process.

  20. The Hanford Site New Production Reactor (NPR) economic and demographic baseline forecasts

    SciTech Connect

    Cluett, C.; Clark, D.C. ); Pittenger, D.B. )

    1990-08-01

    The objective of this is to present baseline employment and population forecasts for Benton, Franklin, and Yakima Counties. These forecasts will be used in the socioeconomic analysis portion of the New Production Reactor Environmental Impact Statement. Aggregate population figures for the three counties in the study area were developed for high- and low-growth scenarios for the study period 1990 through 2040. Age-sex distributions for the three counties during the study period are also presented. The high and low scenarios were developed using high and low employment projections for the Hanford site. Hanford site employment figures were used as input for the HARC-REMI Economic and Demographic (HED) model to produced baseline employment forecasts for the three counties. These results, in turn, provided input to an integrated three-county demographic model. This model, a fairly standard cohort-component model, formalizes the relationship between employment and migration by using migration to equilibrate differences in labor supply and demand. In the resulting population estimates, age-sex distributions for 1981 show the relatively large work force age groups in Benton County while Yakima County reflects higher proportions of the population in the retirement ages. The 2040 forecasts for all three counties reflect the age effects of relatively constant and low fertility increased longevity, as well as the cumulative effects of the migration assumptions in the model. By 2040 the baby boom population will be 75 years and older, contributing to the higher proportion of population in the upper end age group. The low scenario age composition effects are similar. 13 refs., 5 figs., 9 tabs.

  1. Drug versus vaccine investment: a modelled comparison of economic incentives

    PubMed Central

    2013-01-01

    Background Investment by manufacturers in research and development of vaccines is relatively low compared with that of pharmaceuticals. If current evaluation technologies favour drugs over vaccines, then the vaccines market becomes relatively less attractive to manufacturers. Methods We developed a mathematical model simulating the decision-making process of regulators and payers, in order to understand manufacturers’ economic incentives to invest in vaccines rather than curative treatments. We analysed the objectives and strategies of manufacturers and payers when considering investment in technologies to combat a disease that affects children, and the interactions between them. Results The model confirmed that, for rare diseases, the economically justifiable prices of vaccines could be substantially lower than drug prices, and that, for diseases spread across multiple cohorts, the revenues derived from vaccinating one cohort per year (routine vaccination) could be substantially lower than those generated by treating sick individuals. Conclusions Manufacturers may see higher incentives to invest in curative treatments rather than in routine vaccines. To encourage investment in vaccines, health authorities could potentially revise their incentive schemes by: (1) committing to vaccinate all susceptible cohorts in the first year (catch-up campaign); (2) choosing a long-term horizon for health technology evaluation; (3) committing higher budgets for vaccines than for treatments; and (4) taking into account all intangible values derived from vaccines. PMID:24011090

  2. Advanced process modeling at the BCL smelter: Improving economic and environmental performance

    NASA Astrophysics Data System (ADS)

    Tripathi, Nagendra; Peek, Edgar; Stroud, Milton

    2011-01-01

    Since 1973 Bamangwato Concessions Limited (BCL) has operated a nickel-copper smelter in Selebi-Phikwe, Botswana. The smelter treats concentrates from local mines and various custom feed concentrates. The nickel throughput capacity of this smelter is constrained by a low nickel feed grade in its primary BCL concentrate. BCL contracted Xstrata Process Support (XPS) to assist in identifying key economic drivers to maximize revenue-generating opportunities. After the disclosure of essential BCL plant performance data XPS developed and utilized advanced metallurgical modeling techniques to identify production bottlenecks, calculate Ni, Cu, and Co recoveries, manage the slag volumes, increase the custom feed capacity, and perform various feasibility analyses for key unit process operations in the BCL smelter. The methodology for developing the process model and its application in contributing to the economic bottom line are outlined in this paper.

  3. [HERA-QUEST: HTA evaluation of generic pharmaceutical products to improve quality, economic efficiency, patient safety and transparency in drug product changes in hospitals].

    PubMed

    Gyalrong-Steur, Miriam; Kellermann, Anita; Bernard, Rudolf; Berndt, Georg; Bindemann, Meike; Nusser-Rothermundt, Elfriede; Amann, Steffen; Brakebusch, Myga; Brüggmann, Jörg; Tydecks, Eva; Müller, Markus; Dörje, Frank; Kochs, Eberhard; Riedel, Rainer

    2017-04-01

    In view of the rising cost pressure and an increasing number of drug shortages, switches between generic drug preparations have become a daily routine in hospitals. To ensure consistently high treatment quality and best possible patient safety, the equivalence of the new and the previous drug preparation must be ensured before any change in the purchase of pharmaceutical products takes place. So far, no easily usable, transparent and standardized instrument for this kind of comparison between generic drug products has been available. A group of pharmaceutical experts has developed the drug HTA (health technology assessment) model "HERA" (HTA Evaluation of geneRic phArmaceutical products) through a multi-step process. The instrument is designed to perform both a qualitative and economic comparison of equivalent drug preparations ("aut idem" substitution) before switching products. The economic evaluation does not only consider unit prices and consumption quantity, but also the processing costs associated with a product change process. The qualitative comparison is based on the evaluation of 34 quality criteria belonging to six evaluation fields (e.g., approval status, practical handling, packaging design). The objective evaluation of the quality criteria is complemented by an assessment of special features of the individual hospital for complex drug switches, including the feedback of the physicians utilizing the drug preparation. Thus potentially problematic switches of pharmaceutical products can be avoided at the best possible rate, contributing to the improvement of patient safety. The novel drug HTA model HERA is a tool used in clinical practice that can add to an increase in quality, therapeutic safety and transparency of drug use while simultaneously contributing to the economic optimization of drug procurement in hospitals. Combining these two is essential for hospitals facing the tension between rising cost pressure and at the same time increasing demands

  4. Nontimber forest products in Daniel Boone National Forest region--economic significance and potential for sustainability

    Treesearch

    Dasharathi Hembram; William L. Hoover

    2008-01-01

    Household members who gather nontimber forest products (NTFP) in and around the Daniel Boone National Forest (DBNF) in eastern Kentucky were interviewed. Participants reported that a wide variety of NTFP were economically and culturally important to them. Forty-three species of plants were sold commercially and 120 were used in households. Ginseng (Panax...

  5. Futures Symposium. Youth, Work & Economic Productivity: Wisconsin at Risk? Parker Project Number 7. Bulletin No. 4413.

    ERIC Educational Resources Information Center

    Oinonen, Charlotte M.

    These proceedings consist of the texts of papers and panel discussions presented at a Parker Project-sponsored futures symposium on youth, work, economic productivity, and the challenges facing Wisconsin's secondary schools in providing job training for the future. Addressed in the individual presentations included in this volume are the…

  6. Estimating Green Net National Product for Puerto Rico: An Economic Measure of Sustainability (Journal article)

    EPA Science Inventory

    This paper presents the data sources and methodology used to estimate Green Net National Product (GNNP), an economic metric of sustainability, for Puerto Rico. Using the change in GNNP as a one-sided test of weak sustainability (i.e., positive growth in GNNP is not enough to show...

  7. Economic Growth, Productivity, and Public Education Funding: Is South Carolina a Death Spiral State?

    ERIC Educational Resources Information Center

    Driscoll, Lisa G.; Knoeppel, Robert C.; Della Sala, Matthew R.; Watson, Jim R.

    2014-01-01

    As a result of the Great Recession of 2007-2009, most states experienced declines in employment, consumer spending, and economic productivity (Alm, Buschman, and Sjoquist 2011). In turn, these events led to historic declines in state tax revenues (Mikesell and Mullins 2010; Boyd and Dadayan 2009), resulting in major cuts in public spending. Local…

  8. Economic impact of GM crops: the global income and production effects 1996-2012.

    PubMed

    Brookes, Graham; Barfoot, Peter

    2014-01-01

    A key part of any assessment of the global value of crop biotechnology in agriculture is an examination of its economic impact at the farm level. This paper follows earlier annual studies which examined economic impacts on yields, key costs of production, direct farm income and effects, and impacts on the production base of the four main crops of soybeans, corn, cotton and canola. The commercialization of genetically modified (GM) crops has continued to occur at a rapid rate, with important changes in both the overall level of adoption and impact occurring in 2012. This annual updated analysis shows that there have been very significant net economic benefits at the farm level amounting to $18.8 billion in 2012 and $116.6 billion for the 17-year period (in nominal terms). These economic gains have been divided roughly 50% each to farmers in developed and developing countries. GM technology have also made important contributions to increasing global production levels of the four main crops, having added 122 million tonnes and 230 million tonnes respectively, to the global production of soybeans and maize since the introduction of the technology in the mid-1990s.

  9. Economic feasibility of products from inland West small-diameter timber

    Treesearch

    Spelter Henry; Rong Wang; Peter Ince

    1996-01-01

    A large part of the forests located in the Rocky Mountain region of the U.S. West (inland West) is characterized by densely packed, small-diameter stands. The purpose of this study was to examine the economic feasibility of using small-diameter material from this resource to manufacture various wood products: oriented strandboard (OSB), stud lumber, random-length...

  10. Estimating Green Net National Product for Puerto Rico: An Economic Measure of Sustainability (Journal article)

    EPA Science Inventory

    This paper presents the data sources and methodology used to estimate Green Net National Product (GNNP), an economic metric of sustainability, for Puerto Rico. Using the change in GNNP as a one-sided test of weak sustainability (i.e., positive growth in GNNP is not enough to show...

  11. Stimulating the Manufacturing and Distribution of Rehabilitation Products: Economic and Policy Incentives and Disincentives.

    ERIC Educational Resources Information Center

    Scadden, Lawrence A.

    Personal interviews and written correspondence were used to obtain information from 39 officers of companies involved in the manufacture and distribution of rehabilitation-related products, regarding their perceptions of the potential effects of various economic factors and governmental policies. An attempt was made to identify disincentives to…

  12. Economic Growth, Productivity, and Public Education Funding: Is South Carolina a Death Spiral State?

    ERIC Educational Resources Information Center

    Driscoll, Lisa G.; Knoeppel, Robert C.; Della Sala, Matthew R.; Watson, Jim R.

    2014-01-01

    As a result of the Great Recession of 2007-2009, most states experienced declines in employment, consumer spending, and economic productivity (Alm, Buschman, and Sjoquist 2011). In turn, these events led to historic declines in state tax revenues (Mikesell and Mullins 2010; Boyd and Dadayan 2009), resulting in major cuts in public spending. Local…

  13. Principles of Economics Textbooks: Innovation and Product Differentiation--A Response.

    ERIC Educational Resources Information Center

    Sichel, Werner

    1988-01-01

    Focusing on areas of contention, the author responds to "Principles of Economics Textbooks: Innovation and Product Differentiation" by Stiglitz. Contends that Stiglitz's description of principles textbooks is insufficient, states that the textbook market is more oligopolistic than monopolistic, and cautions writers against deleting parts…

  14. The October 1973 NASA mission model analysis and economic assessment

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Results are presented of the 1973 NASA Mission Model Analysis. The purpose was to obtain an economic assessment of using the Shuttle to accommodate the payloads and requirements as identified by the NASA Program Offices and the DoD. The 1973 Payload Model represents a baseline candidate set of future payloads which can be used as a reference base for planning purposes. The cost of implementing these payload programs utilizing the capabilities of the shuttle system is analyzed and compared with the cost of conducting the same payload effort using expendable launch vehicles. There is a net benefit of 14.1 billion dollars as a result of using the shuttle during the 12-year period as compared to using an expendable launch vehicle fleet.

  15. Measuring economic complexity of countries and products: which metric to use?

    NASA Astrophysics Data System (ADS)

    Mariani, Manuel Sebastian; Vidmer, Alexandre; Medo, Matsúš; Zhang, Yi-Cheng

    2015-11-01

    Evaluating the economies of countries and their relations with products in the global market is a central problem in economics, with far-reaching implications to our theoretical understanding of the international trade as well as to practical applications, such as policy making and financial investment planning. The recent Economic Complexity approach aims to quantify the competitiveness of countries and the quality of the exported products based on the empirical observation that the most competitive countries have diversified exports, whereas developing countries only export few low quality products - typically those exported by many other countries. Two different metrics, Fitness-Complexity and the Method of Reflections, have been proposed to measure country and product score in the Economic Complexity framework. We use international trade data and a recent ranking evaluation measure to quantitatively compare the ability of the two metrics to rank countries and products according to their importance in the network. The results show that the Fitness-Complexity metric outperforms the Method of Reflections in both the ranking of products and the ranking of countries. We also investigate a generalization of the Fitness-Complexity metric and show that it can produce improved rankings provided that the input data are reliable.

  16. Chicago School Reform and the Production Model.

    ERIC Educational Resources Information Center

    Valente, Michael E.

    The passage of the Chicago (Illinois) School Reform Act introduced a model of schools called the production model. This model defines the structures of the school by its inputs, throughputs (or production process), and outputs. The production model produces quantitative reports describing the fiscal condition and the quality of output, thus…

  17. Accounting for uncertainty in health economic decision models by using model averaging.

    PubMed

    Jackson, Christopher H; Thompson, Simon G; Sharples, Linda D

    2009-04-01

    Health economic decision models are subject to considerable uncertainty, much of which arises from choices between several plausible model structures, e.g. choices of covariates in a regression model. Such structural uncertainty is rarely accounted for formally in decision models but can be addressed by model averaging. We discuss the most common methods of averaging models and the principles underlying them. We apply them to a comparison of two surgical techniques for repairing abdominal aortic aneurysms. In model averaging, competing models are usually either weighted by using an asymptotically consistent model assessment criterion, such as the Bayesian information criterion, or a measure of predictive ability, such as Akaike's information criterion. We argue that the predictive approach is more suitable when modelling the complex underlying processes of interest in health economics, such as individual disease progression and response to treatment.

  18. A Model For Rapid Estimation of Economic Loss

    NASA Astrophysics Data System (ADS)

    Holliday, J. R.; Rundle, J. B.

    2012-12-01

    One of the loftier goals in seismic hazard analysis is the creation of an end-to-end earthquake prediction system: a "rupture to rafters" work flow that takes a prediction of fault rupture, propagates it with a ground shaking model, and outputs a damage or loss profile at a given location. So far, the initial prediction of an earthquake rupture (either as a point source or a fault system) has proven to be the most difficult and least solved step in this chain. However, this may soon change. The Collaboratory for the Study of Earthquake Predictability (CSEP) has amassed a suite of earthquake source models for assorted testing regions worldwide. These models are capable of providing rate-based forecasts for earthquake (point) sources over a range of time horizons. Furthermore, these rate forecasts can be easily refined into probabilistic source forecasts. While it's still difficult to fully assess the "goodness" of each of these models, progress is being made: new evaluation procedures are being devised and earthquake statistics continue to accumulate. The scientific community appears to be heading towards a better understanding of rupture predictability. Ground shaking mechanics are better understood, and many different sophisticated models exists. While these models tend to be computationally expensive and often regionally specific, they do a good job at matching empirical data. It is perhaps time to start addressing the third step in the seismic hazard prediction system. We present a model for rapid economic loss estimation using ground motion (PGA or PGV) and socioeconomic measures as its input. We show that the model can be calibrated on a global scale and applied worldwide. We also suggest how the model can be improved and generalized to non-seismic natural disasters such as hurricane and severe wind storms.

  19. Economic feasibility of ethanol production from biomass and waste resources via catalytic reaction.

    PubMed

    Yeon, Sun-Hwa; Shin, Dae-Hyun; Nho, Nam-Sun; Shin, Kyoung-Hee; Jin, Chang-Soo

    2013-04-01

    An economic evaluation of ethanol (EtOH) production from a thermo-chemical process derived from biomass/waste feedstocks was conducted. The influence of feed amounts, catalytic conversions, and EtOH selling prices was examined as these are the major variables for the economic evaluation of biomass/wastes conversion to EtOH. Among the three feedstock systems of biomass, high-moisture municipal solid waste (MSW), and plastic waste, the plastic waste has far better economic feasibility, with a payback period of 2-5 years at maximum CO conversion (40%) from syngas to ethanol, due to its higher heating value in comparison with biomass and high-moisture MSW. The heating value of the feedstock is a key factor in determining the overall economic efficiency in a thermo-chemical EtOH production system. Furthermore, enhancement of the CO conversion (related to catalytic activity) from syngas to EtOH using a low cost catalyst is necessary to retain economic efficiency because the CO conversion and cost consideration of catalyst are crucial factors to reduce the payback period.

  20. Technology for Improving Production, Economic Efficiency, Quality, and Sustainability in Peanut Production and Handling

    USDA-ARS?s Scientific Manuscript database

    USDA ARS National Peanut Research Laboratory has a very diverse scientific staff conducting research to address the needs of the United States peanut industry. Research is conducted in the fields of mycology, chemistry, biochemistry, molecular biology, breeding, agronomy, economics, and engineering....

  1. Technology for Improving Production, Economic Efficiency, Quality and Sustainability in Peanut Production and Handling

    USDA-ARS?s Scientific Manuscript database

    USDA ARS National Peanut Research Laboratory has a very diverse scientific staff conducting research to address the needs of the United States peanut industry. Research is conducted in the fields of mycology, chemistry, biochemistry, molecular biology, breeding, agronomy, economics, and engineering....

  2. Technology for improving production, economic efficiency, quality, and sustainability in peanut production and handling

    USDA-ARS?s Scientific Manuscript database

    USDA ARS National Peanut Research Laboratory has a very diverse scientific staff conducting research to address the needs of the United States peanut industry. Research is conducted in the fields of mycology, chemistry, biochemistry, molecular biology, breeding, agronomy, economics, and engineering....

  3. Technology for Improving Production, Economic Efficiency, Quality, and Sustainability in Peanut Production and Handling

    USDA-ARS?s Scientific Manuscript database

    USDA ARS National Peanut Research Laboratory has a very diverse scientific staff conducting research to address the needs of the United States peanut industry. Research is conducted in the fields of mycology, chemistry, biochemistry, molecular biology, breeding, agronomy, economics, and engineering....

  4. The DYNEVAL (Dynamic Economic Values) Model. Volume I. A Generalized Overview,

    DTIC Science & Technology

    1981-05-01

    dynamic balance of value considerations as these considerations are reflected in the power structure of the economy . Whereas most national economic...capital investment and production resources can be allocated within the economy to mitigate the resulting economic damage; and it provides an assessment of...the overall economic impact, assuming an efficient allocation of resources within the economy .

  5. Water security, risk and economic growth: lessons from a dynamical systems model

    NASA Astrophysics Data System (ADS)

    Dadson, Simon; Hall, Jim; Garrick, Dustin; Sadoff, Claudia; Grey, David; Whittington, Dale

    2016-04-01

    Investments in the physical infrastructure, human capital, and institutions needed for water resources management have been a noteworthy feature in the development of most civilisations. These investments affect the economy in two distinct ways: (i) by improving the factor productivity of water in multiple sectors of the economy, especially those that are water intensive such as agriculture and energy; and (ii) by reducing the acute and chronic harmful effects of water-related hazards like floods, droughts, and water-related diseases. The need for capital investment to mitigate these risks in order to promote economic growth is widely acknowledged, but prior work to conceptualise the relationship between water-related risks and economic growth has focused on the productive and harmful roles of water in the economy independently. Here the two influences are combined using a simple, dynamical model of water-related investment, risk, and growth at the national level. The model suggests the existence of a context-specific threshold above which growth proceeds along an 'S'-curve. In many cases there is a requirement for initial investment in water-related assets to enable growth. Below the threshold it is possible for a poverty trap to arise. The presence and location of the poverty trap is context-specific and depends on the relative exposure of productive water-related assets to risk, compared with risks faced by assets in the wider economy. Exogenous changes in the level of water-related risk (through, for example, climate and land cover change) can potentially push an economy away from a growth path towards a poverty trap. These results illustrate the value of accounting for environmental risk in models of economic growth and may offer guidance in the design of robust policies for investment in water-related productive assets to manage risk, particularly in the face of global and regional environmental change.

  6. Social-economic processes of fuel and raw materials region: diversification, mathematical modeling and regularities

    NASA Astrophysics Data System (ADS)

    Novichikhin, A. V.; Fryanov, V. N.; Petrova, T. V.; Pavlova, L. D.; Temlyantsev, M. V.

    2017-09-01

    The paper proposes the structure of production diversification in the fuel and raw material region. A distinctive feature of diversification is the provision of regional reproduction of natural resources – reserves of mineral deposits, as well as fuel and energy deposits – traditionally consumed energy products. The algorithm for determining the regularities of socio-economic processes in the region is developed and the results of its concretization are presented. The difference of the proposed algorithm is the joint accounting of quantitative and qualitative information, the emergence properties of social and economic systems under favorable and the following problem situations: crisis, resource scarcity, uncertainty of the prediction of changes in external conditions, changes in legislative bases. It is suggested to implement identification of possible negative processes at the initial stage and when eliminating them step by step: the formation of a hypothesis about the existence of regularity, cognitive modeling, formulation of statements. Based on the results of cognitive modeling of development scenarios for fuel and raw material regions, a set of statements that form the methodological basis for correcting hypotheses about regularities is justified. Four regularities of social and economic processes of the fuel and raw materials region are revealed.

  7. New economic training model for installing ultrasound-guided drainages.

    PubMed

    Mohr, A; Jung, E M; Stroszczynski, C; Schacherer, D; Klebl, F

    2014-11-01

    Abscesses and circumscribed collections of fluid are frequently found as complications of infectious diseases or surgery. Drainage is often indicated. We have established a new, economic, easy-to-make model to learn and improve competence in installing ultrasound-guided drainage. Up to fifteen water balloons (size 30 - 50 mm) were placed in a plastic box which then was filled with instant custard powder mixed with water. Spiral computed tomography (CT) of this box was performed. Experienced (n = 8) and inexperienced examiners (n = 8) drained the balloons via a direct puncture technique using either ultrasound-guidance alone or volume navigation with image fusion (ultrasound and CT) with needle tracking. Trainees filled out a questionnaire (before and after training) asking for information on their experience in ultrasound, in installing drainages and evaluating the new model. The time needed for installing the drainage was measured. None of the participants had ever attended a course on drainage installation. Only a few of the experienced examiners (n = 3) would autonomously install a drainage into a fluid collection with a size exceeding 4 cm before training. After training all participants felt more confident in ultrasound and in installing drainages into abscesses or other fluid collections. Most of the participants rated additional volume navigation with image fusion as a helpful tool. Ultrasound-guided drainage of abscesses can be trained easily with this new and economic model. Students and physicians can improve their skills and gain confidence in performing ultrasound-guided interventions. © Georg Thieme Verlag KG Stuttgart · New York.

  8. The Future of Food Demand: Understanding Differences in Global Economic Models

    SciTech Connect

    Valin, Hugo; Sands, Ronald; van der Mensbrugghe, Dominique; Nelson, Gerald; Ahammad, Helal; Blanc, Elodie; Bodirsky, Benjamin; Fujimori, Shinichiro; Hasegawa, Tomoko; Havlik, Petr; Heyhoe, Edwina; Kyle, G. Page; Mason d'Croz, Daniel; Paltsev, S.; Rolinski, Susanne; Tabeau, Andrzej; van Meijl, Hans; von Lampe, Martin; Willenbockel, Dirk

    2014-01-01

    Understanding the capacity of agricultural systems to feed the world population under climate change requires a good prospective vision on the future development of food demand. This paper reviews modeling approaches from ten global economic models participating to the AgMIP project, in particular the demand function chosen and the set of parameters used. We compare food demand projections at the horizon 2050 for various regions and agricultural products under harmonized scenarios. Depending on models, we find for a business as usual scenario (SSP2) an increase in food demand of 59-98% by 2050, slightly higher than FAO projection (54%). The prospective for animal calories is particularly uncertain with a range of 61-144%, whereas FAO anticipates an increase by 76%. The projections reveal more sensitive to socio-economic assumptions than to climate change conditions or bioenergy development. When considering a higher population lower economic growth world (SSP3), consumption per capita drops by 9% for crops and 18% for livestock. Various assumptions on climate change in this exercise do not lead to world calorie losses greater than 6%. Divergences across models are however notable, due to differences in demand system, income elasticities specification, and response to price change in the baseline.

  9. Techno-economic analysis of horseradish peroxidase production using a transient expression system in Nicotiana benthamiana.

    PubMed

    Walwyn, David Richard; Huddy, Suzanne M; Rybicki, Edward P

    2015-01-01

    Despite the advantages of plant-based transient expression systems relative to microbial or mammalian cell systems, the commercial production of recombinant proteins using plants has not yet been achieved to any significant extent. One of the challenges has been the lack of published data on the costs of manufacture for products other than biopharmaceuticals. In this study, we report on the techno-economic analysis of the production of a standard commercial enzyme, namely, horseradish peroxidase (HRP), using a transient expression system in Nicotiana benthamiana. Based on the proven plant yield of 240 mg HRP/kg biomass, a biomass productivity of 15-kg biomass/m(2)/year and a process yield of 54 % (mg HRP product/mg HRP in biomass), it is apparent that HRP can be manufactured economically via transient expression in plants in a large-scale facility (>5 kg HRP/year). At this level, the process is competitive versus the existing technology (extraction of the enzyme from horseradish), and the product is of comparable or improved activity, containing only the preferred isoenzyme C. Production scale, protein yield and biomass productivity are found to be the most important determinants of overall viability.

  10. Economic analysis of alcohol production in Thailand and its implication on trade with Japan

    SciTech Connect

    Netayaraks, P.

    1983-01-01

    This research examined the economic feasibility of alcohol production from cassava, sugarcane, and sweet sorghum in 1981 and 1986, and evaluated the economic impact of alcohol production on agriculture output, prices and trade with Japan. Alcohol production from molasses and cassava would be competitive at current energy price levels. Sugarcane, in contrast, would be competitive only if energy prices are increased by 20%, but cassava would still be the preferred choice. The possibility of using cassava or sugarcane as energy feedstocks depends on specific location. Cassava would be used to produce alcohol in the northeast, while energy feedstocks for alcohol production in the central and eastern regions would be either cassava or sugarcane. Energy demand for alcohol as a blended fuel (20% alcohol and 80% gasoline) could be met if energy prices increase 5% above present levels. Complete substitution of alcohol for gasoline (pure fuel) would be possible only if energy prices are increased by 30%. Alcohol exports would be economically possible only after fuel domestic demand had been met. The impact of alcohol production on domestic crop demand, exports and prices depends on the potential alcohol demand and varies by crop.

  11. Pretreatment solution recycling and high-concentration output for economical production of bioethanol.

    PubMed

    Han, Minhee; Moon, Se-Kwon; Choi, Gi-Wook

    2014-11-01

    The purpose of this study was to enhance the economic efficiency of producing bioethanol. Pretreatment solution recycling is expected to increase economic efficiency by reducing the cost of pretreatment and the amount of wastewater. In addition, the production of high-concentration bioethanol could increase economic efficiency by reducing the energy cost of distillation. The pretreatment conditions were 95 °C, 0.72 M NaOH, 80 rpm twin-screw speed, and flow rate of 90 mL/min at 18 g/min of raw biomass feeding for pretreatment solution recycling. The pretreatment with NaOH solution recycling was conducted five times. All of the components and the pretreatment efficiency were similar, despite reuse. In addition, we developed a continuous biomass feeding system for production of high-concentration bioethanol. Using this reactor, the bioethanol productivity was investigated using various pretreated biomass feeding rates in a simultaneous saccharification and fermentation (SSF) process. The maximum ethanol concentration, yield, and productivity were 74.5 g/L, 89.5%, and 1.4 g/L h, respectively, at a pretreated biomass loading of approximately 25% (w/v) with an enzyme dosage of 30 FPU g/cellulose. The results presented here constitute an important contribution toward the production of bioethanol from Miscanthus.

  12. Production effects related to mastitis and mastitis economics in dairy cattle herds.

    PubMed

    Seegers, Henri; Fourichon, Christine; Beaudeau, François

    2003-01-01

    Mastitis is the most prevalent production disease in dairy herds world-wide and is responsible for several production effects. Milk yield and composition can be affected by a more or less severe short-term depression and, in case of no cure, by a long-acting effect, and, sometimes, an overlapping effect to the next lactation. Summary values in the literature for losses of milk production were proposed at 375 kg for a clinical case (5% at the lactation level) and at 0.5 kg per 2-fold increase of crude SCC of a cow. Due to the withdrawal period after treatment, composition changes in milk can almost be neglected in economic calculations. Lethality rate for clinical mastitis is very low on the average, while anticipated culling occurs more frequently after clinical and subclinical mastitis (relative risk between 1.5 and 5.0). The economics of mastitis needs to be addressed at the farm level and, per se, depends on local and regional epidemiological, managerial and economic conditions. To assess the direct economic impact of mastitis, costs (i.e. extra resource use) and losses (i.e. reduced revenues) have to be aggregated. To support decision making for udder health control, it is necessary to use a marginal approach, based on the comparison of the losses avoided and the additional costs of modified plans, compared to the existing ones.

  13. Economic Crisis and Marital Problems in Turkey: Testing the Family Stress Model

    ERIC Educational Resources Information Center

    Aytac, Isik A.; Rankin, Bruce H.

    2009-01-01

    This paper applied the family stress model to the case of Turkey in the wake of the 2001 economic crisis. Using structural equation modeling and a nationally representative urban sample of 711 married women and 490 married men, we tested whether economic hardship and the associated family economic strain on families resulted in greater marital…

  14. A spatial-dynamic value transfer model of economic losses from a biological invasion

    Treesearch

    Thomas P. Holmes; Andrew M. Liebhold; Kent F. Kovacs; Betsy. Von Holle

    2010-01-01

    Rigorous assessments of the economic impacts of introduced species at broad spatial scales are required to provide credible information to policy makers. We propose that economic models of aggregate damages induced by biological invasions need to link microeconomic analyses of site-specific economic damages with spatial-dynamic models of value change associated with...

  15. Economic Analysis of Energy Crop Production in the U.S. - Location, Quantities, Price, and Impacts on Traditional Agricultural Crops

    SciTech Connect

    Walsh, M.E.; De La Torre Ugarte, D.; Slinsky, S.; Graham, R.L.; Shapouri, H.; Ray, D.

    1998-10-04

    POLYSYS is used to estimate US locations where, for any given energy crop price, energy crop production can be economically competitive with conventional crops. POLYSYS is a multi-crop, multi-sector agricultural model developed and maintained by the University of Tennessee and used by the USDA-Economic Research Service. It includes 305 agricultural statistical districts (ASD) which can be aggregated to provide state, regional, and national information. POLYSYS is being modified to include switchgrass, hybrid poplar, and willow on all land suitable for their production. This paper summarizes the preliminary national level results of the POLYSYS analysis for selected energy crop prices for the year 2007 and presents the corresponding maps (for the same prices) of energy crop production locations by ASD. Summarized results include: (1) estimates of energy crop hectares (acres) and quantities (dry Mg, dry tons), (2) identification of traditional crops allocated to energy crop production and calculation of changes in their prices and hectares (acres) of production, and (3) changes in total net farm returns for traditional agricultural crops. The information is useful for identifying areas of the US where large quantities of lowest cost energy crops can most likely be produced.

  16. Job and Economic Development Impact (JEDI) Model: A User-Friendly Tool to Calculate Economic Impacts from Wind Projects; Preprint

    SciTech Connect

    Sinclair, K.; Milligan, M.; Goldberg, M.

    2004-03-01

    The U.S. Department of Energy/National Renewable Energy Laboratory (DOE/NREL) has developed a spreadsheet-based wind model (Jobs and Economic Development Impact (JEDI)) that incorporates economic multipliers for jobs, income, and output. Originally developed with state-specific parameters, it can also be used to conduct county and regional analyses. NREL has enlisted the Wind Powering America (WPA) State Wind Working Groups (SWWGs) to conduct county-specific economic impact analyses and has encouraged them to use JEDI if they do not have their own economic model. The objective of the analyses is to identify counties within WPA target states, and preferably counties with a significant agricultural sector, that could economically benefit from wind development. These counties could then explore opportunities to tap into the United States Department of Agriculture (USDA) Farm Bill Section 9006 grants and loans to stimulate wind development. This paper describes the JEDI model and how i t can be used. We will also summarize a series of analyses that were completed to fulfill a General Accounting Office (GAO) request to provide estimates of the economic development benefits of wind power.

  17. Economic, ecological, and social performance of conventional and organic broiler production in the Netherlands.

    PubMed

    Bokkers, E A M; de Boer, I J M

    2009-09-01

    1. In this study, we compared a conventional broiler production system keeping fast growing broilers with an organic broiler production system keeping slow growing broilers in the Netherlands, both managed by one person working a full time year (Full Time Equivalent, FTE). This comparison was based on a quantification of economic, ecological and social indicators. Indicators were quantified using scientific literature and national data sets. 2. The organic system performed better for the economic indicator net farm income per FTE than the conventional system. 3. Regarding ecological indicators, calculations showed a higher on-farm emission of ammonia per kg live weight for the organic system. Moreover, an organic system includes a higher risk for eutrophication per ha due to outdoor access. Emission of green house gasses, use of fossil fuels and use of land required for the production of one kg of live weight is higher for an organic than for a conventional system. This is mainly due to a lower feed conversion in organic production and use of organic feed. 4. The organic system performed better than the conventional system for the social indicators related to animal welfare time spent on walking, footpad lesions, mortality, and sound legs. Regarding the social indicator food safety was found that meat from an organic system contained less antibiotic residues and Salmonella contaminations but more Campylobacter contaminations than meat from a conventional system. 5. Changing from a conventional to an organic broiler production system, therefore, not only affects animal welfare, but also affects economic, ecological and other social issues. In this study, we ran into the situation that some information needed was lacking in literature and quantifications had to be based upon several sources. Therefore, an integrated on-farm assessment is needed, which can be used to develop a broiler production system that is economically profitable, ecologically sound, and

  18. Medico-economic evaluation of health products in the context of the Social Security Financing Act for 2012.

    PubMed

    Dervaux, Benoît; Baseilhac, Eric; Fagon, Jean-Yves; Ameye, Véronique; Angot, Pierre; Audry, Antoine; Becquemont, Laurent; Borel, Thomas; Cazeneuve, Béatrice; Courtois, Jocelyn; Detournay, Bruno; Favre, Pascal; Granger, Muriel; Josseran, Anne; Lassale, Catherine; Louvet, Olivier; Pinson, Jean; de Pouvourville, Gérard; Rochaix, Lise; Rumeau-Pichon, Catherine; de Saab, Rima; Schwarzinger, Mickaël; Sun, Aristide

    2013-01-01

    The participants in round table 6 of the Giens Workshops 2012 drafted recommendations based on the collective interpretation of important elements of the decree concerning the medico-economic evaluation of health products published a few days earlier (02 October 2012). The medico-economic evaluation (MEE), becomes an additional determinant for fixing the prices of health products by the Health products economic committee (Comité économique des produits de santé, CEPS) via the hierarchisation of treatment strategies, and thus modifies the market access conditions. Limiting the analysis to medicinal products and medical devices for which a major, important or moderate improvement in the medical service rendered (ASMR) or of the expected service (ASA) has been requested and presenting a significant budget impact on the Social Security expenses, excludes health products with ASMR or ASA with a lower level requested which often create complex price fixing problems and often have a major budget impact. This latter concept remains to be defined in detail. The MEE envisaged for the first registration must include the need to confirm or refute the initial hypotheses especially concerning the actual position in the therapeutic strategy at the time of renewal of the registration. For the first registration, the conventional reference to European prices guaranteeing a minimum price to innovative medicinal products, the medico-economic models submitted by the industry to the French Drug Authority (Haute autorité de santé, HAS) must be used to guide the compilation of new data to be requested at the time of the registration renewal and to negotiate the level of the discounts in the framework of a price-volume agreement, if applicable. The MEE will allow comparing the result of the analysis to the model hypothesis at the time of the renewal of the registration, which may contribute to the renegotiation (either up or down) of the price of health goods. The costs related to

  19. A noticeable difference? Productivity costs related to paid and unpaid work in economic evaluations on expensive drugs.

    PubMed

    Krol, Marieke; Papenburg, Jocé; Tan, Siok Swan; Brouwer, Werner; Hakkaart, Leona

    2016-05-01

    Productivity costs can strongly impact cost-effectiveness outcomes. This study investigated the impact in the context of expensive hospital drugs. This study aimed to: (1) investigate the effect of productivity costs on cost-effectiveness outcomes, (2) determine whether economic evaluations of expensive drugs commonly include productivity costs related to paid and unpaid work, and (3) explore potential reasons for excluding productivity costs from the economic evaluation. We conducted a systematic literature review to identify economic evaluations of 33 expensive drugs. We analysed whether evaluations included productivity costs and whether inclusion or exclusion was related to the study population's age, health and national health economic guidelines. The impact on cost-effectiveness outcomes was assessed in studies that included productivity costs. Of 249 identified economic evaluations of expensive drugs, 22 (9 %) included productivity costs related to paid work. One study included unpaid productivity. Mostly, productivity cost exclusion could not be explained by the study population's age and health status, but national guidelines appeared influential. Productivity costs proved often highly influential. This study indicates that productivity costs in economic evaluations of expensive hospital drugs are commonly and inconsistently ignored in economic evaluations. This warrants caution in interpreting and comparing the results of these evaluations.

  20. Revisiting the Economic Injury Level and Economic Threshold Model for Potato Leafhopper (Hemiptera: Cicadellidae) in Alfalfa.

    PubMed

    Chasen, Elissa M; Undersander, Dan J; Cullen, Eileen M

    2015-08-01

    The economic injury level for potato leafhopper, Empoasca fabae (Harris), in alfalfa (Medicago sativa L.) was developed over 30 yr ago. In response to increasing market value of alfalfa, farmers and consultants are interested in reducing the economic threshold for potato leafhopper in alfalfa. To address this question, caged field trials were established on two consecutive potato leafhopper susceptible crops in 2013. Field cages were infested with a range of potato leafhopper densities to create a linear regression of alfalfa yield response. The slopes, or yield loss per insect, for the linear regressions of both trials were used to calculate an economic injury level for a range of current alfalfa market values and control costs. This yield-loss relationship is the first quantification that could be used to help assess whether the economic threshold should be lowered, given the increased market value of alfalfa.

  1. Economics of recombinant antibody production processes at various scales: Industry-standard compared to continuous precipitation.

    PubMed

    Hammerschmidt, Nikolaus; Tscheliessnig, Anne; Sommer, Ralf; Helk, Bernhard; Jungbauer, Alois

    2014-06-01

    Standard industry processes for recombinant antibody production employ protein A affinity chromatography in combination with other chromatography steps and ultra-/diafiltration. This study compares a generic antibody production process with a recently developed purification process based on a series of selective precipitation steps. The new process makes two of the usual three chromatographic steps obsolete and can be performed in a continuous fashion. Cost of Goods (CoGs) analyses were done for: (i) a generic chromatography-based antibody standard purification; (ii) the continuous precipitation-based purification process coupled to a continuous perfusion production system; and (iii) a hybrid process, coupling the continuous purification process to an upstream batch process. The results of this economic analysis show that the precipitation-based process offers cost reductions at all stages of the life cycle of a therapeutic antibody, (i.e. clinical phase I, II and III, as well as full commercial production). The savings in clinical phase production are largely attributed to the fact that expensive chromatographic resins are omitted. These economic analyses will help to determine the strategies that are best suited for small-scale production in parallel fashion, which is of importance for antibody production in non-privileged countries and for personalized medicine.

  2. Biofuel production system with operation flexibility: Evaluation of economic and environmental performance under external disturbance

    NASA Astrophysics Data System (ADS)

    Kou, Nannan

    Biomass derived liquid hydrocarbon fuel (biofuel) has been accepted as an effective way to mitigate the reliance on petroleum and reduce the greenhouse gas emissions. An increasing demand for second generation biofuels, produced from ligno-cellulosic feedstock and compatible with current infrastructure and vehicle technologies, addresses two major challenges faced by the current US transportation sector: energy security and global warming. However, biofuel production is subject to internal disturbances (feedstock supply and commodity market) and external factors (energy market). The biofuel industry has also heavily relied on government subsidy during the early development stages. In this dissertation, I investigate how to improve the economic and environmental performance of biorefineries (and biofuel plant), as well as enhance its survivability under the external disturbances. Three types of disturbance are considered: (1) energy market fluctuation, (2) subsidy policy uncertainty, and (3) extreme weather conditions. All three factors are basically volatile, dynamic, and even unpredictable, which makes them difficult to model and have been largely ignored to date. Instead, biofuel industry and biofuel research are intensively focused on improving feedstock conversion efficiency and capital cost efficiency while assuming these advancements alone will successfully generate higher profit and thus foster the biofuel industry. The collapse of the largest corn ethanol biofuel company, Verasun Energy, in 2008 calls into question this efficiency-driven approach. A detailed analysis has revealed that although the corn ethanol plants operated by Verasun adopted the more efficient (i.e. higher ethanol yield per bushel of corn and lower capital cost) dry-mill technology, they could not maintain a fair profit margin under fluctuating market condition which made ethanol production unprofitable. This is because dry-mill plant converts a single type of biomass feedstock (corn

  3. Local and Regional Economic Benefits from Forest Products Production Activities at the Savannah River Site: 1955-Present

    SciTech Connect

    Teeter, L.; Blake, J.I.

    2002-01-01

    SRS was established in 1951 as a nuclear materials production facility; however, decline in the defense mission budget at SRS has created a major economic impact on the community in the Central Savannah River Area. SRS has been offsetting these effects by producing revenue (80 million dollars to date) from the sale of forest products since 1955 primarily trees, but also pine straw. Revenue has been re-invested into the infrastructure development, restoration and management of natural resources. Total asset value of the forest-land has increased from 21 million to over 500 million dollars in the same period.

  4. Mars Colony in situ resource utilization: An integrated architecture and economics model

    NASA Astrophysics Data System (ADS)

    Shishko, Robert; Fradet, René; Do, Sydney; Saydam, Serkan; Tapia-Cortez, Carlos; Dempster, Andrew G.; Coulton, Jeff

    2017-09-01

    This paper reports on our effort to develop an ensemble of specialized models to explore the commercial potential of mining water/ice on Mars in support of a Mars Colony. This ensemble starts with a formal systems architecting framework to describe a Mars Colony and capture its artifacts' parameters and technical attributes. The resulting database is then linked to a variety of ;downstream; analytic models. In particular, we integrated an extraction process (i.e., ;mining;) model, a simulation of the colony's environmental control and life support infrastructure known as HabNet, and a risk-based economics model. The mining model focuses on the technologies associated with in situ resource extraction, processing, storage and handling, and delivery. This model computes the production rate as a function of the systems' technical parameters and the local Mars environment. HabNet simulates the fundamental sustainability relationships associated with establishing and maintaining the colony's population. The economics model brings together market information, investment and operating costs, along with measures of market uncertainty and Monte Carlo techniques, with the objective of determining the profitability of commercial water/ice in situ mining operations. All told, over 50 market and technical parameters can be varied in order to address ;what-if; questions, including colony location.

  5. Techno-economic analysis of advanced biofuel production based on bio-oil gasification.

    PubMed

    Li, Qi; Zhang, Yanan; Hu, Guiping

    2015-09-01

    This paper evaluates the economic feasibility of an integrated production pathway combining fast pyrolysis and bio-oil gasification. The conversion process is simulated with Aspen Plus® for a 2000 metric ton per day facility. Techno-economic analysis of this integrated pathway has been conducted. A total capital investment of $510 million has been estimated and the minimum fuel selling price (MSP) is $5.59 per gallon of gasoline equivalent. The sensitivity analysis shows that the MSP is most sensitive to internal rate of return, fuel yield, biomass feedstock cost, and fixed capital investment. Monte-Carlo simulation shows that MSP for bio-oil gasification would be more than $6/gal with a probability of 0.24, which indicates this pathway is still at high risk with current economic and technical situation.

  6. Assessing economic consequences of foot disorders in dairy cattle using a dynamic stochastic simulation model.

    PubMed

    Bruijnis, M R N; Hogeveen, H; Stassen, E N

    2010-06-01

    Foot disorders are an important health problem in dairy cattle, in terms of economics and animal welfare. The incidence, severity, and duration of foot disorders account for their importance. Prevalence of both subclinical and clinical foot disorders is high. More insight into the economic consequences could increase awareness among dairy farmers and could be an incentive for them to take action on this problem of animal welfare. The objective of this research was to estimate the economic consequences of different types of foot disorders, both clinical and subclinical. A dynamic stochastic Monte Carlo simulation model was used, taking into account the different types of foot disorders. The economic consequences of the foot disorders modeled were costs due to milk production losses, culling, prolonged calving interval, labor of the dairy farmer and the foot trimmer, visits of a veterinarian, treatment, and discarded milk. Under the milk quota system in The Netherlands, costs due to foot disorders for a default farm with 65 cows averaged $4,899 per year (ranging from $3,217 to $7,001), an annual loss of $75 per cow. This calculation implies that the costs due to foot disorders are more substantial than farmers might think. The costs of subclinical foot disorders account for 32% of all costs due to foot disorders. The costs due to foot disorders that are present without treatment or detection by the farmer are considerable. This finding implies that farmers might underestimate the benefits of taking action earlier and more thoroughly. A clinical foot disorder costs, on average, $95, and a subclinical foot disorder $18. The highest costs classified by foot disorder were those due to digital dermatitis, which has a high incidence and relatively high clinical prevalence. The highest costs classified by cost factor were those due to milk production losses and culling. Sensitivity analysis showed that variables regarding milk production were important for economic costs

  7. An economic and ecological perspective of ethanol production from renewable agro waste: a review.

    PubMed

    Bhatia, Latika; Johri, Sonia; Ahmad, Rumana

    2012-12-07

    Agro-industrial wastes are generated during the industrial processing of agricultural products. These wastes are generated in large amounts throughout the year, and are the most abundant renewable resources on earth. Due to the large availability and composition rich in compounds that could be used in other processes, there is a great interest on the reuse of these wastes, both from economical and environmental view points. The economic aspect is based on the fact that such wastes may be used as low-cost raw materials for the production of other value-added compounds, with the expectancy of reducing the production costs. The environmental concern is because most of the agro-industrial wastes contain phenolic compounds and/or other compounds of toxic potential; which may cause deterioration of the environment when the waste is discharged to the nature. Although the production of bioethanol offers many benefits, more research is needed in the aspects like feedstock preparation, fermentation technology modification, etc., to make bioethanol more economically viable.

  8. An economic and ecological perspective of ethanol production from renewable agro waste: a review

    PubMed Central

    2012-01-01

    Agro-industrial wastes are generated during the industrial processing of agricultural products. These wastes are generated in large amounts throughout the year, and are the most abundant renewable resources on earth. Due to the large availability and composition rich in compounds that could be used in other processes, there is a great interest on the reuse of these wastes, both from economical and environmental view points. The economic aspect is based on the fact that such wastes may be used as low-cost raw materials for the production of other value-added compounds, with the expectancy of reducing the production costs. The environmental concern is because most of the agro-industrial wastes contain phenolic compounds and/or other compounds of toxic potential; which may cause deterioration of the environment when the waste is discharged to the nature. Although the production of bioethanol offers many benefits, more research is needed in the aspects like feedstock preparation, fermentation technology modification, etc., to make bioethanol more economically viable. PMID:23217124

  9. Sustainability and economics: The Adirondack Park experience, a forest economic-ecological model, and solar energy policy

    NASA Astrophysics Data System (ADS)

    Erickson, Jon David

    The long-term sustainability of human communities will depend on our relationship with regional environments, our maintenance of renewable resources, and our successful disengagement from nonrenewable energy dependence. This dissertation investigates sustainability at these three levels, following a critical analysis of sustainability and economics. At the regional environment level, the Adirondack Park of New York State is analyzed as a potential model of sustainable development. A set of initial and ongoing conditions are presented that both emerge from and support a model of sustainability in the Adirondacks. From these conditions, a clearer picture emerges of the definition of regional sustainability, consequences of its adoption, and lessons from its application. Next, an economic-ecological model of the northern hardwood forest ecosystem is developed. The model integrates economic theory and intertemporal ecological concepts, linking current harvest decisions with future forest growth, financial value, and ecosystem stability. The results indicate very different economic and ecological outcomes by varying opportunity cost and ecosystem recovery assumptions, and suggest a positive benefit to ecological recovery in the forest rotation decision of the profit maximizing manager. The last section investigates the motives, economics, and international development implications of renewable energy (specifically photovoltaic technology) in rural electrification and technology transfer, drawing on research in the Dominican Republic. The implications of subsidizing a photovoltaic market versus investing in basic research are explored.

  10. Commercial Plant Production and Consumption Still Follow the Latitudinal Gradient in Species Diversity despite Economic Globalization.

    PubMed

    Nelson, Erik J; Helmus, Matthew R; Cavender-Bares, Jeannine; Polasky, Stephen; Lasky, Jesse R; Zanne, Amy E; Pearse, William D; Kraft, Nathan J B; Miteva, Daniela A; Fagan, William F

    2016-01-01

    Increasing trade between countries and gains in income have given consumers around the world access to a richer and more diverse set of commercial plant products (i.e., foods and fibers produced by farmers). According to the economic theory of comparative advantage, countries open to trade will be able to consume more-in terms of volume and diversity-if they concentrate production on commodities that they can most cost-effectively produce, while importing goods that are expensive to produce, relative to other countries. Here, we perform a global analysis of traded commercial plant products and find little evidence that increasing globalization has incentivized agricultural specialization. Instead, a country's plant production and consumption patterns are still largely determined by local evolutionary legacies of plant diversification. Because tropical countries harbor a greater diversity of lineages across the tree of life than temperate countries, tropical countries produce and consume a greater diversity of plant products than do temperate countries. In contrast, the richer and more economically advanced temperate countries have the capacity to produce and consume more plant species than the generally poorer tropical countries, yet this collection of plant species is drawn from fewer branches on the tree of life. Why have countries not increasingly specialized in plant production despite the theoretical financial incentive to do so? Potential explanations include the persistence of domestic agricultural subsidies that distort production decisions, cultural preferences for diverse local food production, and that diverse food production protects rural households in developing countries from food price shocks. Less specialized production patterns will make crop systems more resilient to zonal climatic and social perturbations, but this may come at the expense of global crop production efficiency, an important step in making the transition to a hotter and more

  11. Commercial Plant Production and Consumption Still Follow the Latitudinal Gradient in Species Diversity despite Economic Globalization

    PubMed Central

    Nelson, Erik J.; Helmus, Matthew R.; Cavender-Bares, Jeannine; Polasky, Stephen; Lasky, Jesse R.; Zanne, Amy E.; Pearse, William D.; Kraft, Nathan J. B.; Miteva, Daniela A.; Fagan, William F.

    2016-01-01

    Increasing trade between countries and gains in income have given consumers around the world access to a richer and more diverse set of commercial plant products (i.e., foods and fibers produced by farmers). According to the economic theory of comparative advantage, countries open to trade will be able to consume more–in terms of volume and diversity–if they concentrate production on commodities that they can most cost-effectively produce, while importing goods that are expensive to produce, relative to other countries. Here, we perform a global analysis of traded commercial plant products and find little evidence that increasing globalization has incentivized agricultural specialization. Instead, a country’s plant production and consumption patterns are still largely determined by local evolutionary legacies of plant diversification. Because tropical countries harbor a greater diversity of lineages across the tree of life than temperate countries, tropical countries produce and consume a greater diversity of plant products than do temperate countries. In contrast, the richer and more economically advanced temperate countries have the capacity to produce and consume more plant species than the generally poorer tropical countries, yet this collection of plant species is drawn from fewer branches on the tree of life. Why have countries not increasingly specialized in plant production despite the theoretical financial incentive to do so? Potential explanations include the persistence of domestic agricultural subsidies that distort production decisions, cultural preferences for diverse local food production, and that diverse food production protects rural households in developing countries from food price shocks. Less specialized production patterns will make crop systems more resilient to zonal climatic and social perturbations, but this may come at the expense of global crop production efficiency, an important step in making the transition to a hotter and more

  12. Fermion masses in the economical 3-3-1 model

    SciTech Connect

    Dong, P. V.; Huong, Tr. T.; Huong, D. T.; Long, H. N.

    2006-09-01

    We show that, in frameworks of the economical 3-3-1 model, all fermions get masses. At the tree level, one up-quark and two down-quarks are massless, but the one-loop corrections give all quarks the consistent masses. This conclusion is in contradiction to the previous analysis in which the third scalar triplet has been introduced. This result is based on the key properties of the model: First, there are three quite different scales of vacuum expectation values: {omega}{approx}O(1) TeV, v{approx_equal}246 GeV, and u{approx}O(1) GeV. Second, there exist two types of Yukawa couplings with different strengths: the lepton-number conserving couplings h's and the lepton-number violating ones s's satisfying the condition in which the second are much smaller than the first ones: s<model, masses of the exotic quarks also have different scales, namely, the U exotic quark (q{sub U}=2/3) gains mass m{sub U}{approx_equal}700 GeV, while the D{sub {alpha}} exotic quarks (q{sub D{sub {alpha}}}=-1/3) have masses in the TeV scale: m{sub D{sub {alpha}}}(set-membership sign)10-80 TeV.

  13. The environmental and economic impact of removing growth-enhancing technologies from U.S. beef production.

    PubMed

    Capper, J L; Hayes, D J

    2012-10-01

    The objective of this study was to quantify the environmental and economic impact of withdrawing growth-enhancing technologies (GET) from the U.S. beef production system. A deterministic model based on the metabolism and nutrient requirements of the beef population was used to quantify resource inputs and waste outputs per 454 × 10(6) kg of beef. Two production systems were compared: one using GET (steroid implants, in-feed ionophores, in-feed hormones, and beta-adrenergic agonists) where approved by FDA at current adoption rates and the other without GET use. Both systems were modeled using characteristic management practices, population dynamics, and production data from U.S. beef systems. The economic impact and global trade and carbon implications of GET withdrawal were calculated based on feed savings. Withdrawing GET from U.S. beef production reduced productivity (growth rate and slaughter weight) and increased the population size required to produce 454 × 10(6) kg beef by 385 × 10(3) animals. Feedstuff and land use were increased by 2,830 × 10(3) t and 265 × 10(3) ha, respectively, by GET withdrawal, with 20,139 × 10(6) more liters of water being required to maintain beef production. Manure output increased by 1,799 × 10(3) t as a result of GET withdrawal, with an increase in carbon emissions of 714,515 t/454 × 10(6) kg beef. The projected increased costs of U.S. beef produced without GET resulted in the effective implementation of an 8.2% tax on beef production, leading to reduced global trade and competitiveness. To compensate for the increase in U.S. beef prices and maintain beef supply, it would be necessary to increase beef production in other global regions, with a projected increase in carbon emissions from deforestation, particularly in Brazil. Withdrawing GET from U.S. beef production would reduce both the economic and environmental sustainability of the industry.

  14. Spatial pattern of diarrhea based on regional economic and environment by spatial autoregressive model

    NASA Astrophysics Data System (ADS)

    Bekti, Rokhana Dwi; Nurhadiyanti, Gita; Irwansyah, Edy

    2014-10-01

    The diarrhea case pattern information, especially for toddler, is very important. It is used to show the distribution of diarrhea in every region, relationship among that locations, and regional economic characteristic or environmental behavior. So, this research uses spatial pattern to perform them. This method includes: Moran's I, Spatial Autoregressive Models (SAR), and Local Indicator of Spatial Autocorrelation (LISA). It uses sample from 23 sub districts of Bekasi Regency, West Java, Indonesia. Diarrhea case, regional economic, and environmental behavior of households have a spatial relationship among sub district. SAR shows that the percentage of Regional Gross Domestic Product is significantly effect on diarrhea at α = 10%. Therefore illiteracy and health center facilities are significant at α = 5%. With LISA test, sub districts in southern Bekasi have high dependencies with Cikarang Selatan, Serang Baru, and Setu. This research also builds development application that is based on java and R to support data analysis.

  15. Techno-Economic Analysis of Liquid Fuel Production from Woody Biomass via Hydrothermal Liquefaction (HTL) and Upgrading

    SciTech Connect

    Zhu, Yunhua; Biddy, Mary J.; Jones, Susanne B.; Elliott, Douglas C.; Schmidt, Andrew J.

    2014-09-15

    A series of experimental work was conducted to convert woody biomass to gasoline and diesel range products via hydrothermal liquefaction (HTL) and catalytic hydroprocessing. Based on the best available test data, a techno-economic analysis (TEA) was developed for a large scale woody biomass based HTL and upgrading system to evaluate the feasibility of this technology. In this system, 2000 dry metric ton per day woody biomass was assumed to be converted to bio-oil in hot compressed water and the bio-oil was hydrotreated and/or hydrocracked to produce gasoline and diesel range liquid fuel. Two cases were evaluated: a stage-of-technology (SOT) case based on the tests results, and a goal case considering potential improvements based on the SOT case. Process simulation models were developed and cost analysis was implemented based on the performance results. The major performance results included final products and co-products yields, raw materials consumption, carbon efficiency, and energy efficiency. The overall efficiency (higher heating value basis) was 52% for the SOT case and 66% for the goal case. The production cost, with a 10% internal rate of return and 2007 constant dollars, was estimated to be $1.29 /L for the SOT case and $0.74 /L for the goal case. The cost impacts of major improvements for moving from the SOT to the goal case were evaluated and the assumption of reducing the organics loss to the water phase lead to the biggest reduction in the production cost. Sensitivity analysis indicated that the final products yields had the largest impact on the production cost compared to other parameters. Plant size analysis demonstrated that the process was economically attractive if the woody biomass feed rate was over 1,500 dry tonne/day, the production cost was competitive with the then current petroleum-based gasoline price.

  16. The economics of bootstrapping space industries - Development of an analytic computer model

    NASA Technical Reports Server (NTRS)

    Goldberg, A. H.; Criswell, D. R.

    1982-01-01

    A simple economic model of 'bootstrapping' industrial growth in space and on the Moon is presented. An initial space manufacturing facility (SMF) is assumed to consume lunar materials to enlarge the productive capacity in space. After reaching a predetermined throughput, the enlarged SMF is devoted to products which generate revenue continuously in proportion to the accumulated output mass (such as space solar power stations). Present discounted value and physical estimates for the general factors of production (transport, capital efficiency, labor, etc.) are combined to explore optimum growth in terms of maximized discounted revenues. It is found that 'bootstrapping' reduces the fractional cost to a space industry of transport off-Earth, permits more efficient use of a given transport fleet. It is concluded that more attention should be given to structuring 'bootstrapping' scenarios in which 'learning while doing' can be more fully incorporated in program analysis.

  17. The economics of bootstrapping space industries - Development of an analytic computer model

    NASA Technical Reports Server (NTRS)

    Goldberg, A. H.; Criswell, D. R.

    1982-01-01

    A simple economic model of 'bootstrapping' industrial growth in space and on the Moon is presented. An initial space manufacturing facility (SMF) is assumed to consume lunar materials to enlarge the productive capacity in space. After reaching a predetermined throughput, the enlarged SMF is devoted to products which generate revenue continuously in proportion to the accumulated output mass (such as space solar power stations). Present discounted value and physical estimates for the general factors of production (transport, capital efficiency, labor, etc.) are combined to explore optimum growth in terms of maximized discounted revenues. It is found that 'bootstrapping' reduces the fractional cost to a space industry of transport off-Earth, permits more efficient use of a given transport fleet. It is concluded that more attention should be given to structuring 'bootstrapping' scenarios in which 'learning while doing' can be more fully incorporated in program analysis.

  18. The Productivity Factor. Comparing Japanese and American Modes of Production. A Resource for Teachers of Economics.

    ERIC Educational Resources Information Center

    Copley, Paul

    Focusing on the human element through a cross-cultural comparison of U.S. and Japanese modes of production, this resource guide features an assessment of the major factors that affect productivity performance. Each section contains a goal statement and an overview outline of the featured topics. The text includes primary sources, such as documents…

  19. The Productivity Factor. Comparing Japanese and American Modes of Production. A Resource for Teachers of Economics.

    ERIC Educational Resources Information Center

    Copley, Paul

    Focusing on the human element through a cross-cultural comparison of U.S. and Japanese modes of production, this resource guide features an assessment of the major factors that affect productivity performance. Each section contains a goal statement and an overview outline of the featured topics. The text includes primary sources, such as documents…

  20. Measuring the Intangibles: A Metrics for the Economic Complexity of Countries and Products

    PubMed Central

    Cristelli, Matthieu; Gabrielli, Andrea; Tacchella, Andrea; Caldarelli, Guido; Pietronero, Luciano

    2013-01-01

    We investigate a recent methodology we have proposed to extract valuable information on the competitiveness of countries and complexity of products from trade data. Standard economic theories predict a high level of specialization of countries in specific industrial sectors. However, a direct analysis of the official databases of exported products by all countries shows that the actual situation is very different. Countries commonly considered as developed ones are extremely diversified, exporting a large variety of products from very simple to very complex. At the same time countries generally considered as less developed export only the products also exported by the majority of countries. This situation calls for the introduction of a non-monetary and non-income-based measure for country economy complexity which uncovers the hidden potential for development and growth. The statistical approach we present here consists of coupled non-linear maps relating the competitiveness/fitness of countries to the complexity of their products. The fixed point of this transformation defines a metrics for the fitness of countries and the complexity of products. We argue that the key point to properly extract the economic information is the non-linearity of the map which is necessary to bound the complexity of products by the fitness of the less competitive countries exporting them. We present a detailed comparison of the results of this approach directly with those of the Method of Reflections by Hidalgo and Hausmann, showing the better performance of our method and a more solid economic, scientific and consistent foundation. PMID:23940633

  1. An economic assessment of astaxanthin production by large scale cultivation of Haematococcus pluvialis.

    PubMed

    Li, Jian; Zhu, Daling; Niu, Jianfeng; Shen, Songdong; Wang, Guangce

    2011-01-01

    Although natural sources have long been exploited for astaxanthin production, it is still uncertain if natural astaxanthin can be produced at lower cost than that of synthetic astaxanthin or not. In order to give a comprehensive cost analysis of astaxanthin production from Haematococcus, a pilot plant with two large scale outdoor photobioreactors and a raceway pond was established and operated for 2 years to develop processes for astaxanthin production from Haematococcus. The developed processes were scaled up to a hypothetical plant with a production capacity about 900 kg astaxanthin per year, and the process economics was preliminarily assessed. Based on the analysis, the production cost of astaxanthin and microalgae biomass can be as low as $718/kg and $18/kg respectively. The results are very encouraging because the estimated cost might be lower than that of chemically synthesized astaxanthin.

  2. Techno-economic evaluation of a combined bioprocess for fermentative hydrogen production from food waste.

    PubMed

    Han, Wei; Fang, Jun; Liu, Zhixiang; Tang, Junhong

    2016-02-01

    In this study, the techno-economic evaluation of a combined bioprocess based on solid state fermentation for fermentative hydrogen production from food waste was carried out. The hydrogen production plant was assumed to be built in Hangzhou and designed for converting 3 ton food waste per day into hydrogen. The total capital cost (TCC) and the annual production cost (APC) were US$583092 and US$88298.1/year, respectively. The overall revenue after the tax was US$146473.6/year. The return on investment (ROI), payback period (PBP) and internal rate of return (IRR) of the plant were 26.75%, 5 years and 24.07%, respectively. The results exhibited that the combined bioprocess for hydrogen production from food waste was feasible. This is an important study for attracting investment and industrialization interest for hydrogen production from food waste in the industrial scale. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Matrix Shrinkage and Swelling Effects on Economics of Enhanced Coalbed Methane Production and CO2 Sequestration in Coal

    SciTech Connect

    Gorucu, F.B.; Jikich, S.A.; Bromhal, G.S.; Sams, W.N.; Ertekin, T.; Smith, D.H.

    2005-09-01

    Increases in CO2 levels in the atmosphere and their contributions to global climate change have been a major concern. It has been shown that CO2 injection can enhance the methane recovery from coal. Accordingly, sequestration costs can be partially offset by the value added product. Indeed, coal seam sequestration may be profitable, particularly with the introduction of incentives for CO2 sequestration. Hence, carbon dioxide sequestration in unmineable coals is a very attractive option, not only for environmental reasons, but also for possible economic benefits. Darcy flow through cleats is an important transport mechanism in coal. Cleat compression and permeability changes due to gas sorption desorption, changes of effective stress, and matrix swelling and shrinkage introduce a high level of complexity into the feasibility of a coal sequestration project. The economic effects of carbon dioxide-induced swelling on permeabilities and injectivities has received little (if any) detailed attention. Carbon dioxide and methane have different swelling effects on coal. In this work, the Palmer-Mansoori model for coal shrinkage and permeability increases during primary methane production was re-written to also account for coal swelling caused by carbon dioxide sorption. The generalized model was added to PSU-COALCOMP, a dual porosity reservoir simulator for primary and enhanced coalbed methane production. A standard five-spot of vertical wells and representative coal properties for Appalachian coals were used.[1] Simulations and sensitivity analyses were performed with the modified simulator for nine different parameters, including coal seam and operational parameters and economic criteria. The coal properties and operating parameters that were varied included Young’s modulus, Poisson’s ratio, the cleat porosity, and the injection pressure. The economic variables included CH4 price, CO2 cost, CO2 credit, water disposal cost, and interest rate. Net present value analyses

  4. Estimation of economic values for traits of dairy sheep: I. Model development.

    PubMed

    Wolfová, M; Wolf, J; Krupová, Z; Kica, J

    2009-05-01

    A bioeconomic model was developed to estimate effects of change in production and functional traits on profit of dairy or dual-purpose milked sheep under alternative management systems. The flock structure was described in terms of animal categories and probabilities of transitions among them, and a Markov chain approach was used to calculate the stationary state of the resultant ewe flock. The model included both deterministic and stochastic components. Performance for most traits was simulated as the population average, but variation in several traits was taken into account. Management options included lambing intervals, mating system, and culling strategy for ewes, weaning and marketing strategy for progeny, and feeding system. The present value of profit computed as the difference between total revenues and total costs per ewe per year, both discounted to the birth date of the animals, was used as the criterion for economic efficiency of the production system in the stationary state. Economic values (change in system profit per unit change in the trait) of up to 35 milk production, growth, carcass, wool, and functional traits may be estimated.

  5. MODELING JOINT PRODUCTION OF WILDLIFE AND TIMBER

    EPA Science Inventory

    Production of marketed commodities and protection of natural systems often conflict. A
    focus on only one goal can result in large losses in other goals and may result in inefficient and
    unsustainable outcomes. In this paper we develop a method that combines economic and
    ...

  6. MODELING JOINT PRODUCTION OF WILDLIFE AND TIMBER

    EPA Science Inventory

    Production of marketed commodities and protection of natural systems often conflict. A
    focus on only one goal can result in large losses in other goals and may result in inefficient and
    unsustainable outcomes. In this paper we develop a method that combines economic and
    ...

  7. Current challenges in health economic modeling of cancer therapies: a research inquiry.

    PubMed

    Miller, Jeffrey D; Foley, Kathleen A; Russell, Mason W

    2014-05-01

    The demand for economic models that evaluate cancer treatments is increasing, as healthcare decision makers struggle for ways to manage their budgets while providing the best care possible to patients with cancer. Yet, after nearly 2 decades of cultivating and refining techniques for modeling the cost-effectiveness and budget impact of cancer therapies, serious methodologic and policy challenges have emerged that question the adequacy of economic modeling as a sound decision-making tool in oncology. We sought to explore some of the contentious issues associated with the development and use of oncology economic models as informative tools in current healthcare decision-making. Our objective was to draw attention to these complex pharmacoeconomic concerns and to promote discussion within the oncology and health economics research communities. Using our combined expertise in health economics research and economic modeling, we structured our inquiry around the following 4 questions: (1) Are economic models adequately addressing questions relevant to oncology decision makers; (2) What are the methodologic limitations of oncology economic models; (3) What guidelines are followed for developing oncology economic models; and (4) Is the evolution of oncology economic modeling keeping pace with treatment innovation? Within the context of each of these questions, we discuss issues related to the technical limitations of oncology modeling, the availability of adequate data for developing models, and the problems with how modeling analyses and results are presented and interpreted. There is general acceptance that economic models are good, essential tools for decision-making, but the practice of oncology and its rapidly evolving technologies present unique challenges that make assessing and demonstrating value especially complex. There is wide latitude for improvement in oncology modeling methodologies and how model results are presented and interpreted. Complex technical and

  8. Current Challenges in Health Economic Modeling of Cancer Therapies: A Research Inquiry

    PubMed Central

    Miller, Jeffrey D.; Foley, Kathleen A.; Russell, Mason W.

    2014-01-01

    Background The demand for economic models that evaluate cancer treatments is increasing, as healthcare decision makers struggle for ways to manage their budgets while providing the best care possible to patients with cancer. Yet, after nearly 2 decades of cultivating and refining techniques for modeling the cost-effectiveness and budget impact of cancer therapies, serious methodologic and policy challenges have emerged that question the adequacy of economic modeling as a sound decision-making tool in oncology. Objectives We sought to explore some of the contentious issues associated with the development and use of oncology economic models as informative tools in current healthcare decision-making. Our objective was to draw attention to these complex pharmacoeconomic concerns and to promote discussion within the oncology and health economics research communities. Methods Using our combined expertise in health economics research and economic modeling, we structured our inquiry around the following 4 questions: (1) Are economic models adequately addressing questions relevant to oncology decision makers; (2) What are the methodologic limitations of oncology economic models; (3) What guidelines are followed for developing oncology economic models; and (4) Is the evolution of oncology economic modeling keeping pace with treatment innovation? Within the context of each of these questions, we discuss issues related to the technical limitations of oncology modeling, the availability of adequate data for developing models, and the problems with how modeling analyses and results are presented and interpreted. Discussion There is general acceptance that economic models are good, essential tools for decision-making, but the practice of oncology and its rapidly evolving technologies present unique challenges that make assessing and demonstrating value especially complex. There is wide latitude for improvement in oncology modeling methodologies and how model results are presented

  9. Environmental and economic assessment of a road safety product made with virgin and recycled HDPE: a comparative study.

    PubMed

    L Simões, Carla; Costa Pinto, Lígia M; Bernardo, C A

    2013-01-15

    The development of value-added products made from post-consumer plastic recyclates has become an important goal in the quest for a sustainable society. To attain such goal, tools with higher accuracy and wider scope are increasingly necessary. The present work describes the application of a Life Cycle Assessment (LCA)/Life Cycle Costing (LCC) integrated model, with inclusion of externalities (environmental and social costs), to Anti-Glare Lamellae (AGL) made with High Density Polyethylene (HDPE). It compares an AGL currently manufactured from virgin HDPE (current AGL) with an alternative one made with recycled HDPE (optional AGL). The results obtained show that neither the current nor the optional AGL depict the best environmental performance in all impact categories. Nevertheless, there is a clear overall environmental and economic advantage in replacing virgin HDPE with recycled HDPE. The present work also makes evident that the LCA/LCC integrated model allows the identification of economic and environmental win-win and trade-off situations related to the full life cycle of products. As such, its results can be used as valuable guidelines in product development. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Climate Impact and Economic Feasibility of Solar Thermochemical Jet Fuel Production.

    PubMed

    Falter, Christoph; Batteiger, Valentin; Sizmann, Andreas

    2016-01-05

    Solar thermochemistry presents a promising option for the efficient conversion of H2O and CO2 into liquid hydrocarbon fuels using concentrated solar energy. To explore the potential of this fuel production pathway, the climate impact and economic performance are analyzed. Key drivers for the economic and ecological performance are thermochemical energy conversion efficiency, the level of solar irradiation, operation and maintenance, and the initial investment in the fuel production plant. For the baseline case of a solar tower concentrator with CO2 capture from air, jet fuel production costs of 2.23 €/L and life cycle greenhouse gas (LC GHG) emissions of 0.49 kgCO2-equiv/L are estimated. Capturing CO2 from a natural gas combined cycle power plant instead of the air reduces the production costs by 15% but leads to LC GHG emissions higher than that of conventional jet fuel. Favorable assumptions for all involved process steps (30% thermochemical energy conversion efficiency, 3000 kWh/(m(2) a) solar irradiation, low CO2 and heliostat costs) result in jet fuel production costs of 1.28 €/L at LC GHG emissions close to zero. Even lower production costs may be achieved if the commercial value of oxygen as a byproduct is considered.

  11. Feedlot of lambs fed biodiesel co-products: performance, commercial cuts and economic evaluation.

    PubMed

    Romanzini, Eliéder Prates; da Silva Sobrinho, Américo Garcia; de Lima Valença, Roberta; Borghi, Thiago Henrique; de Andrade, Nomaiací; Bernardes, Priscila Arrigucci

    2017-09-23

    The aim of this study was to evaluate the animal performance, commercial cuts, and their yields within the production system, and economics of sheep production, of lambs finished in feedlots and fed with or without biodiesel co-products. A total of 40 lambs were divided into four biodiesel co-product treatment groups: a no-treatment control; peanut meal; crude glycerin; and peanut meal + crude glycerin. Animal performance did not differ (P > 0.05) among the treatment groups, where the average daily gain was close to 0.26 kg/day. Likewise, the quantitative carcass characteristics did not differ (P > 0.05) and the biological mean yield was 54.92%. Similarly, the commercial cuts and their yields did not differ (P ≥ 0.09) among the treatments. These results took into consideration the standard, age, and slaughter body weight of the animals. The economic evaluation determined that peanut meal was the best co-product for use in finishing lambs in a feedlot. Hence, all the biodiesel co-products evaluated can be used at feedlots to finish lambs without changing the variables measured.

  12. Economic analysis for utilization of geothermal energy by North Dakota Concrete Products Co.

    SciTech Connect

    Zink, L.L.

    1982-02-01

    North Dakota Concrete Products Company uses a steam curing process that accelerates the concrete curing so that 28-day strength is obtained within 24 hours. The cost of energy required to accomplish this is significant, amounting to approximately $80,000 in 1980. The present boilers are oil fired. Recently, fuel oil prices have increased substantially. Further, supply shortages in the past have threatened plant production. The purpose of this study was to evaluate the economic feasibility of using deep formation warm water as an alternative energy source. A water-to-water heat pump system to replace the existing boiler system was investigated. TPI, Inc. economic and engineering findings for this particular potential geothermal application are disclosed. The operating cost savings of the geothermal system over the operating costs of the existing oilfired system would be insufficient to provide an acceptable rate of return on the investment at todays cost of money.

  13. Cleaner production in the ammonia-soda industry: an ecological and economic study.

    PubMed

    Kasikowski, T; Buczkowski, R; Lemanowska, E

    2004-12-01

    Five methods to reduce the negative influence of soda ash factories on the natural environment are presented: 1. obtaining calcium-magnesium phosphates by treating the suspension from raw brine purification with orthophosphoric acid (H(3)PO(4)), 2. production of precipitated chalk from soda processing waste, 3. production of gypsum and semi-brine, 4. desulphurisation of fume gases from the factory power plant, 5. utilization of distiller waste. The tests, accomplished on a laboratory scale, showed the high efficiency of these methods. Economic analysis has proved that only four out of the five presented processes can have a positive financial effect on soda ash factories, as well as being well justified economically. The value of two of the innovations presented is confirmed by their implementation in factories.

  14. Quantity and economic importance of nine selected by-products used in California dairy rations.

    PubMed

    Grasser, L A; Fadel, J G; Garnett, I; DePeters, E J

    1995-04-01

    Food processing representatives, brokers, nutritionists, livestock producers, and trade associations were surveyed to quantify 9 by-products used for feeding livestock during 1992 in California. The commodities were almond hulls, dried beet pulp, wet brewers grains, wet citrus pulp, pressed citrus pulp, wet corn gluten feed, corn gluten meal, whole cottonseed, and rice bran. The 9 by-products contributed over 2.5 million tonnes and about 27% of the total feed concentrate moved within California during 1992. Market value of these 9 by-products was almost .25 billion dollars. Whole cottonseed accounted for about 31% of the total tonnage of these 9 by-products and provided about 66% of the total CP and 53% of the total NEL of these 9 by-products. The by-products were more valuable as energy sources than CP sources compared with NEL from corn and CP from soybean meal, respectively. Calculations of milk production, based on the CP content or NEL content of the by-products, showed that these 9 by-products could have contributed sufficient CP or NEL for over 31% of the milk produced in California during 1992. Ration formulations demonstrated that the economic value of by-products changed with feedstuffs available and, in general, would be used in rations over a range of market prices.

  15. Increasing Feedstock Production for Biofuels: Economic Drivers, Environmental Implications, and the Role of Research

    SciTech Connect

    none,

    2009-10-27

    The Biomass Research and Development Board (Board) commissioned an economic analysis of feedstocks to produce biofuels. The Board seeks to inform investments in research and development needed to expand biofuel production. This analysis focuses on feedstocks; other interagency teams have projects underway for other parts of the biofuel sector (e.g., logistics). The analysis encompasses feedstocks for both conventional and advanced biofuels from agriculture and forestry sources.

  16. An economical device for carbon supplement in large-scale micro-algae production.

    PubMed

    Su, Zhenfeng; Kang, Ruijuan; Shi, Shaoyuan; Cong, Wei; Cai, Zhaoling

    2008-10-01

    One simple but efficient carbon-supplying device was designed and developed, and the correlative carbon-supplying technology was described. The absorbing characterization of this device was studied. The carbon-supplying system proved to be economical for large-scale cultivation of Spirulina sp. in an outdoor raceway pond, and the gaseous carbon dioxide absorptivity was enhanced above 78%, which could reduce the production cost greatly.

  17. Economic feasibility of products from inland west small-diameter timber. Forest Service general technical report

    SciTech Connect

    Spelter, H.; Wang, R.; Ince, P.

    1996-05-01

    A large part of the forests located in the Rocky Mountain region of the U.S. West (inland West) is characterized by densely packed, small-diameter stands. The purpose of this study was to examine the economic feasibility of using small-diameter material from this resource to manufacture various wood products: oriented strandboard (OSB), stud lumber, random-length dimension lumber, machine-stress-rated random-length lumber, laminated veneer lumber (LVL), and market pulp.

  18. Ethanol production in southwestern New York: technical and economic feasibility. Final report

    SciTech Connect

    Not Available

    1981-01-01

    Based upon the analysis conducted for this study, the development of centralized ethanol conversion facilities in the Steuben and Allegany Counties is likely to be commercially feasible if either locally produced cheese whey and/or imported corn are used as feedstocks. Development is shown to be profitable under a broad range of potential economic conditions and technical considerations. Four plant designs varying in annual production capacity from 1.675 to 27.5 million gallons of ethanol (and utilizing alternative conversion technologies and feedstocks) are investigated. In general, all of the various plant sizes investigated are economically viable. Although economic profitability is enhanced by the existence of federal subsidies, in the form of $0.40 per gallon from federal gasoline tax rebates, energy investment tax credits and low interest loans, a public subsidy is not necessary, under most conditions, to ensure the economic feasibility of any of the plant design investigated. In all cases, a by-product in the form of an animal feed is produced, thereby generating additional revenue for the conversion facility and adding to the likelihood of commercial feasibility. In the case of the corn/whey plant, the by-product takes the form of a distillers dried grain. In the case of the whey plants, it takes the form of a high mineral, medium protein feed supplement for low and moderate producing dairy cattle. Both have a ready market in the study region. Fermenting of deproteinized whey to produce ethanol and drying the resulting distillation slops for animal feed completely utilizes the original cheese whey. The techniques developed in this study produce three valuable products and leave no residual requiring disposal.

  19. Public sector administration of ecological economics systems using mediated modeling.

    PubMed

    van den Belt, Marjan; Kenyan, Jennifer R; Krueger, Elizabeth; Maynard, Alison; Roy, Matthew Galen; Raphael, Ian

    2010-01-01

    In today's climate of government outsourcing and multiple stakeholder involvement in public sector management and service delivery, it is more important than ever to rethink and redesign the structure of how policy decisions are made, implemented, monitored, and adapted to new realities. The traditional command-and-control approach is now less effective because an increasing amount of responsibility to deliver public goods and services falls on networks of nongovernment agencies. Even though public administrators are seeking new decision-making models in an increasingly more complex environment, the public sector currently only sparsely utilizes Mediated Modeling (MM). There is growing evidence, however, that by employing MM and similar tools, public interest networks can be better equipped to deal with their long-term viability while maintaining the short-term needs of their clients. However, it may require a shift in organizational culture within and between organizations to achieve the desired results. This paper explores the successes and barriers to implementing MM and similar tools in the public sector and offers insights into utilizing them through a review of case studies and interdisciplinary literature. We aim to raise a broader interest in MM and similar tools among public sector administrators at various administrative levels. We focus primarily, but not exclusively, on those cases operating at the interface of ecology and socio-economic systems.

  20. Non-smooth plant disease models with economic thresholds.

    PubMed

    Zhao, Tingting; Xiao, Yanni; Smith, Robert J

    2013-01-01

    In order to control plant diseases and eventually maintain the number of infected plants below an economic threshold, a specific management strategy called the threshold policy is proposed, resulting in Filippov systems. These are a class of piecewise smooth systems of differential equations with a discontinuous right-hand side. The aim of this work is to investigate the global dynamic behavior including sliding dynamics of one Filippov plant disease model with cultural control strategy. We examine a Lotka-Volterra Filippov plant disease model with proportional planting rate, which is globally studied in terms of five types of equilibria. For one type of equilibrium, the global structure is discussed by the iterative equations for initial numbers of plants. For the other four types of equilibria, the bounded global attractor of each type is obtained by constructing appropriate Lyapunov functions. The ideas of constructing Lyapunov functions for Filippov systems, the methods of analyzing such systems and the main results presented here provide scientific support for completing control regimens on plant diseases in integrated disease management. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Current technologies, economics, and perspectives for 2,5-dimethylfuran production from biomass-derived intermediates.

    PubMed

    Saha, Basudeb; Abu-Omar, Mahdi M

    2015-04-13

    Since the U.S. Department of Energy (DOE) published a perspective article that described the potential of the top ten biomass-derived platform chemicals as petroleum replacements for high-value commodity and specialty chemicals, researchers around the world have been motivated to develop technologies for the conversion of biomass and biomass-derived intermediates into chemicals and fuels. Among several biorefinery processes, the conversion of biomass carbohydrates into 2,5-dimethylfuran (DMF) has received significant attention because of its low oxygen content, high energy content, and high octane value. DMF can further serve as a petroleum-replacement, biorenewable feedstock for the production of p-xylene (pX). In this review, we aim specifically to present a concise and up-to-date analysis of DMF production technologies with a critical discussion on catalytic systems, mechanistic insight, and process economics, which includes sensitivity analysis, so that more effective catalysts can be designed. Special emphasis has been given to bifunctional catalysts that improve DMF yields and selectivity and the synergistic effect of the bifunctional sites. Process economics for the current processes and the scope for further improvement are discussed. It is anticipated that the chemistry detailed in this review will guide researchers to develop more practical catalytic processes to enable the economic production of bio-based DMF. Processes for the upgrade of DMF to pX are also described.

  2. Geologic and economic case histories of Upper Devonian natural gas production in Pennsylvania

    SciTech Connect

    Mangini, K.N.

    1988-08-01

    The Upper Devonian gas sands of western Pennsylvania have been commercially exploited since the turn of the century. The economic success of this exploitation may be attributed to the existence of multiply-stacked or en echelon reservoirs. The serendipity of development drilling coupled with multiple reservoirs made drilling for Upper Devonian gas very attractive to operators. As a result of many years of concentrated drilling, a current shortage of Upper Devonian developmental prospects exists and is forcing operators to explore nearshore more sporadically deposited Devonian sand reservoirs. The depositional modeling of developed areas can, however, help identify new prospective areas for exploration and development and increase economic success.

  3. Economic tools for realization of methane production project on Kuzbass coal deposits

    NASA Astrophysics Data System (ADS)

    Sharf, I.; Sokolova, M.; Kochetkova, O.; Dmitrieva, N.

    2016-09-01

    Environmental issues and, above all, issues related to the release of greenhouse gases into the atmosphere, such as coal bed methane, actualize the challenge of searching a variety of options for its disposal. The difference in the macroeconomic, industrial, geological and infrastructural features determine the need to choose the most cost-effective option for using of methane emitted from the coal deposits. Various economic ways to improve the profitability of production are viewed on the basis of the analysis of methane production project from Kuzbass coal deposits, Kemerovo region, Russia.

  4. Biofuels and Their Co-Products as Livestock Feed: Global Economic and Environmental Implications.

    PubMed

    Popp, József; Harangi-Rákos, Mónika; Gabnai, Zoltán; Balogh, Péter; Antal, Gabriella; Bai, Attila

    2016-02-29

    This review studies biofuel expansion in terms of competition between conventional and advanced biofuels based on bioenergy potential. Production of advanced biofuels is generally more expensive than current biofuels because products are not yet cost competitive. What is overlooked in the discussion about biofuel is the contribution the industry makes to the global animal feed supply and land use for cultivation of feedstocks. The global ethanol industry produces 44 million metric tonnes of high-quality feed, however, the co-products of biodiesel production have a moderate impact on the feed market contributing to just 8-9 million tonnes of protein meal output a year. By economically displacing traditional feed ingredients co-products from biofuel production are an important and valuable component of the biofuels sector and the global feed market. The return of co-products to the feed market has agricultural land use (and GHG emissions) implications as well. The use of co-products generated from grains and oilseeds can reduce net land use by 11% to 40%. The proportion of global cropland used for biofuels is currently some 2% (30-35 million hectares). By adding co-products substituted for grains and oilseeds the land required for cultivation of feedstocks declines to 1.5% of the global crop area.

  5. A nonlinear model of gold production in Malaysia

    NASA Astrophysics Data System (ADS)

    Ramli, Norashikin; Muda, Nora; Umor, Mohd Rozi

    2014-06-01

    Malaysia is a country which is rich in natural resources and one of it is a gold. Gold has already become an important national commodity. This study is conducted to determine a model that can be well fitted with the gold production in Malaysia from the year 1995-2010. Five nonlinear models are presented in this study which are Logistic model, Gompertz, Richard, Weibull and Chapman-Richard model. These model are used to fit the cumulative gold production in Malaysia. The best model is then selected based on the model performance. The performance of the fitted model is measured by sum squares error, root mean squares error, coefficient of determination, mean relative error, mean absolute error and mean absolute percentage error. This study has found that a Weibull model is shown to have significantly outperform compare to the other models. To confirm that Weibull is the best model, the latest data are fitted to the model. Once again, Weibull model gives the lowest readings at all types of measurement error. We can concluded that the future gold production in Malaysia can be predicted according to the Weibull model and this could be important findings for Malaysia to plan their economic activities.

  6. Acetone-butanol-ethanol fermentation of corn stover: current production methods, economic viability and commercial use.

    PubMed

    Baral, Nawa R; Slutzky, Lauren; Shah, Ajay; Ezeji, Thaddeus C; Cornish, Katrina; Christy, Ann

    2016-03-01

    Biobutanol is a next-generation liquid biofuel with properties akin to those of gasoline. There is a widespread effort to commercialize biobutanol production from agricultural residues, such as corn stover, which do not compete with human and animal foods. This pursuit is backed by extensive government mandates to expand alternative energy sources. This review provides an overview of research on biobutanol production using corn stover feedstock. Structural composition, pretreatment, sugar yield (following pretreatment and hydrolysis) and generation of lignocellulose-derived microbial inhibitory compounds (LDMICs) from corn stover are discussed. The review also discusses different Clostridium species and strains employed for biobutanol production from corn stover-derived sugars with respect to solvent yields, tolerance to LDMICs and in situ solvent recovery (integrated fermentation). Further, the economics of cellulosic biobutanol production are highlighted and compared to corn starch-derived ethanol and gasoline. As discussed herein, the economic competitiveness of biobutanol production from corn stover largely depends on feedstock processing and fermentation process design. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Techno-economic analysis of bioethanol production from rice straw by liquid-state fermentation

    NASA Astrophysics Data System (ADS)

    Hidayata, M. H. M.; Salleh, S. F.; Riayatsyahb, T. M. I.; Aditiyac, H. B.; Mahliaa, T. M. I.; Shamsuddina, A. H.

    2016-03-01

    Renewable energy is the latest approach of the Malaysian government in an effort to find sustainable alternative energy sources and to fulfill the ever increasing energy demand. Being a country that thrives in the service and agricultural sector, bioethanol production from lignocellulosic biomass presents itself as a promising option. However, the lack of technical practicality and complexity in the operation system hinder it from being economically viable. Hence, this research acquired multiple case studies in order to provide an insight on the process involved and its implication on production as well as to obtain a cost analysis of bioethanol production. The energy input and cost of three main components of the bioethanol production which are the collection, logistics, and pretreatment of rice straw were evaluated extensively. The theoretical bioethanol yield and conversion efficiency obtained were 250 L/t and 60% respectively. The findings concluded that bioethanol production from rice straw is currently not economically feasible in Malaysia’s market due to lack of efficiency in the pretreatment phase and overbearing logistics and pretreatment costs. This work could serve as a reference to future studies of biofuel commercialization in Malaysia.

  8. A technical, economic, and environmental analysis of energy production from newspaper in Ireland.

    PubMed

    Murphy, J D; Power, N

    2007-01-01

    The production of newspaper corresponds to 37 kg per person per annum in Ireland. Newspaper becomes a waste product in a short period of time; only 13% of domestic waste paper is recycled (data on newspaper is not available). Four scenarios, which generate energy from newspaper, are analysed. These scenarios may be summarised as follows: lignocellulosic biomass conversion to ethanol (transport fuel); co-digestion with the organic fraction of municipal solid waste and production of CH4-enriched biogas (transport fuel); co-firing with the residue of municipal solid waste in an incinerator; and gasification of newspaper as a sole fuel. Two of the scenarios involve transport fuel production; two involve the production of electricity and heat. Two of the scenarios involve newspaper as the sole ingredient; two involve co- utilisation of newspaper with another waste stream. Assuming no economic market for heat, then only the transport scenarios have the potential to be economic; indeed the biogas scenario is shown to be extremely competitive generating a potential profit of euro 227/t newspaper. A greenhouse-gas analysis indicates that the biogas scenario generated the best net greenhouse-gas savings. However when a market for heat is available, gasification was shown to be most advantageous.

  9. A hydro-economic modelling framework for optimal management of groundwater nitrate pollution from agriculture

    NASA Astrophysics Data System (ADS)

    Peña-Haro, Salvador; Pulido-Velazquez, Manuel; Sahuquillo, Andrés

    2009-06-01

    SummaryA hydro-economic modelling framework is developed for determining optimal management of groundwater nitrate pollution from agriculture. A holistic optimization model determines the spatial and temporal fertilizer application rate that maximizes the net benefits in agriculture constrained by the quality requirements in groundwater at various control sites. Since emissions (nitrogen loading rates) are what can be controlled, but the concentrations are the policy targets, we need to relate both. Agronomic simulations are used to obtain the nitrate leached, while numerical groundwater flow and solute transport simulation models were used to develop unit source solutions that were assembled into a pollutant concentration response matrix. The integration of the response matrix in the constraints of the management model allows simulating by superposition the evolution of groundwater nitrate concentration over time at different points of interest throughout the aquifer resulting from multiple pollutant sources distributed over time and space. In this way, the modelling framework relates the fertilizer loads with the nitrate concentration at the control sites. The benefits in agriculture were determined through crop prices and crop production functions. This research aims to contribute to the ongoing policy process in the Europe Union (the Water Framework Directive) providing a tool for analyzing the opportunity cost of measures for reducing nitrogen loadings and assessing their effectiveness for maintaining groundwater nitrate concentration within the target levels. The management model was applied to a hypothetical groundwater system. Optimal solutions of fertilizer use to problems with different initial conditions, planning horizons, and recovery times were determined. The illustrative example shows the importance of the location of the pollution sources in relation to the control sites, and how both the selected planning horizon and the target recovery time can

  10. Economic evaluation of technology for a new generation biofuel production using wastes.

    PubMed

    Koutinas, Athanasios; Kanellaki, Maria; Bekatorou, Argyro; Kandylis, Panagiotis; Pissaridi, Katerina; Dima, Agapi; Boura, Konstantina; Lappa, Katerina; Tsafrakidou, Panagiota; Stergiou, Panagiota-Yiolanda; Foukis, Athanasios; Gkini, Olga A; Papamichael, Emmanuel M

    2016-01-01

    An economic evaluation of an integrated technology for industrial scale new generation biofuel production using whey, vinasse, and lignocellulosic biomass as raw materials is reported. Anaerobic packed-bed bioreactors were used for organic acids production using initially synthetic media and then wastes. Butyric, lactic and acetic acid were predominately produced from vinasse, whey, and cellulose, respectively. Mass balance was calculated for a 16,000L daily production capacity. Liquid-liquid extraction was applied for recovery of the organic acids using butanol-1 as an effective extraction solvent which serves also as the alcohol for the subsequent enzyme-catalyzed esterification. The investment needed for the installation of the factory was estimated to about 1.7million€ with depreciation excepted at about 3months. For cellulosics, the installation investment was estimated to be about 7-fold higher with depreciation at about 1.5years. The proposed technology is an alternative trend in biofuel production.

  11. Converting citrus wastes into value-added products: Economic and environmently friendly approaches.

    PubMed

    Sharma, Kavita; Mahato, Neelima; Cho, Moo Hwan; Lee, Yong Rok

    2017-02-01

    Citrus fruits, including oranges, grapefruits, lemons, limes, tangerines, and mandarins, are among the most widely cultivated fruits around the globe. Its production is increasing every year due to rising consumer demand. Citrus-processing industries generate huge amounts of wastes every year, and citrus peel waste alone accounts for almost 50% of the wet fruit mass. Citrus waste is of immense economic value as it contains an abundance of various flavonoids, carotenoids, dietary fiber, sugars, polyphenols, essential oils, and ascorbic acid, as well as considerable amounts of some trace elements. Citrus waste also contains high levels of sugars suitable for fermentation for bioethanol production. However, compounds such as D-limonene must be removed for efficient bioethanol production. The aim of the present article was to review the latest advances in various popular methods of extraction for obtaining value-added products from citrus waste/byproducts and their potential utility as a source of various functional compounds.

  12. Biohydrogen production from waste bread in a continuous stirred tank reactor: A techno-economic analysis.

    PubMed

    Han, Wei; Hu, Yun Yi; Li, Shi Yi; Li, Fei Fei; Tang, Jun Hong

    2016-12-01

    Biohydrogen production from waste bread in a continuous stirred tank reactor (CSTR) was techno-economically assessed. The treating capacity of the H2-producing plant was assumed to be 2 ton waste bread per day with lifetime of 10years. Aspen Plus was used to simulate the mass and energy balance of the plant. The total capital investment (TCI), total annual production cost (TAPC) and annual revenue of the plant were USD931020, USD299746/year and USD639920/year, respectively. The unit hydrogen production cost was USD1.34/m(3) H2 (or USD14.89/kg H2). The payback period and net present value (NPV) of the plant were 4.8years and USD1266654, respectively. Hydrogen price and operators cost were the most important variables on the NPV. It was concluded that biohydrogen production from waste bread in the CSTR was feasible for practical application.

  13. Production of activated carbons from waste tire--process design and economical analysis.

    PubMed

    Ko, Danny C K; Mui, Edward L K; Lau, Ken S T; McKay, Gordon

    2004-01-01

    The process design and economic analysis of process plants to produce activated carbons from waste tires and coal have been performed. The potential range of products from each process has been considered, namely for waste tire--pyro-gas, active carbon, carbon black and pyro-oil; for coal--pyro-gas and active carbons. Sensitivity analyses have been carried out on the main process factors; these are product price, production capacity, total production cost, capital investment and the tipping fee. Net present values for the two plants at various discount factors have been determined and the internal rates of return have been determined as 27.4% and 18.9% for the waste tire plant and the coal plant, respectively.

  14. A satellite-driven, client-server hydro-economic model prototype for agricultural water management

    NASA Astrophysics Data System (ADS)

    Maneta, Marco; Kimball, John; He, Mingzhu; Payton Gardner, W.

    2017-04-01

    Anticipating agricultural water demand, land reallocation, and impact on farm revenues associated with different policy or climate constraints is a challenge for water managers and for policy makers. While current integrated decision support systems based on programming methods provide estimates of farmer reaction to external constraints, they have important shortcomings such as the high cost of data collection surveys necessary to calibrate the model, biases associated with inadequate farm sampling, infrequent model updates and recalibration, model overfitting, or their deterministic nature, among other problems. In addition, the administration of water supplies and the generation of policies that promote sustainable agricultural regions depend on more than one bureau or office. Unfortunately, managers from local and regional agencies often use different datasets of variable quality, which complicates coordinated action. To overcome these limitations, we present a client-server, integrated hydro-economic modeling and observation framework driven by satellite remote sensing and other ancillary information from regional monitoring networks. The core of the framework is a stochastic data assimilation system that sequentially ingests remote sensing observations and corrects the parameters of the hydro-economic model at unprecedented spatial and temporal resolutions. An economic model of agricultural production, based on mathematical programming, requires information on crop type and extent, crop yield, crop transpiration and irrigation technology. A regional hydro-climatologic model provides biophysical constraints to an economic model of agricultural production with a level of detail that permits the study of the spatial impact of large- and small-scale water use decisions. Crop type and extent is obtained from the Cropland Data Layer (CDL), which is multi-sensor operational classification of crops maintained by the United States Department of Agriculture. Because

  15. Big Think: A Model for Critical Inquiry in Economics Courses

    ERIC Educational Resources Information Center

    McGoldrick, KimMarie; Garnett, Robert

    2013-01-01

    Economic educators often profess the goal of teaching our students to "think like economists." Since Siegfried and colleagues (1991) coined this phrase, its meaning has been interpreted as a focus on analytical concepts and methods of economics as opposed to the broader goal of preparing students for independent, critical thought in the…

  16. A Simple Model of Entrepreneurship for Principles of Economics Courses

    ERIC Educational Resources Information Center

    Gunter, Frank R.

    2012-01-01

    The critical roles of entrepreneurs in creating, operating, and destroying markets, as well as their importance in driving long-term economic growth are still generally either absent from principles of economics texts or relegated to later chapters. The primary difficulties in explaining entrepreneurship at the principles level are the lack of a…

  17. A Simple Model of Entrepreneurship for Principles of Economics Courses

    ERIC Educational Resources Information Center

    Gunter, Frank R.

    2012-01-01

    The critical roles of entrepreneurs in creating, operating, and destroying markets, as well as their importance in driving long-term economic growth are still generally either absent from principles of economics texts or relegated to later chapters. The primary difficulties in explaining entrepreneurship at the principles level are the lack of a…

  18. A hydro-economic model for water level fluctuations: combining limnology with economics for sustainable development of hydropower.

    PubMed

    Hirsch, Philipp Emanuel; Schillinger, Sebastian; Weigt, Hannes; Burkhardt-Holm, Patricia

    2014-01-01

    Water level fluctuations in lakes lead to shoreline displacement. The seasonality of flooding or beaching of the littoral area affects nutrient cycling, redox gradients in sediments, and life cycles of aquatic organisms. Despite the ecological importance of water level fluctuations, we still lack a method that assesses water levels in the context of hydropower operations. Water levels in reservoirs are influenced by the operator of a hydropower plant, who discharges water through the turbines or stores water in the reservoir, in a fashion that maximizes profit. This rationale governs the seasonal operation scheme and hence determines the water levels within the boundaries of the reservoir's water balance. For progress towards a sustainable development of hydropower, the benefits of this form of electricity generation have to be weighed against the possible detrimental effects of the anthropogenic water level fluctuations. We developed a hydro-economic model that combines an economic optimization function with hydrological estimators of the water balance of a reservoir. Applying this model allowed us to accurately predict water level fluctuations in a reservoir. The hydro-economic model also allowed for scenario calculation of how water levels change with climate change scenarios and with a change in operating scheme of the reservoir (increase in turbine capacity). Further model development will enable the consideration of a variety of additional parameters, such as water withdrawal for irrigation, drinking water supply, or altered energy policies. This advances our ability to sustainably manage water resources that must meet both economic and environmental demands.

  19. A Hydro-Economic Model for Water Level Fluctuations: Combining Limnology with Economics for Sustainable Development of Hydropower

    PubMed Central

    Hirsch, Philipp Emanuel; Schillinger, Sebastian; Weigt, Hannes; Burkhardt-Holm, Patricia

    2014-01-01

    Water level fluctuations in lakes lead to shoreline displacement. The seasonality of flooding or beaching of the littoral area affects nutrient cycling, redox gradients in sediments, and life cycles of aquatic organisms. Despite the ecological importance of water level fluctuations, we still lack a method that assesses water levels in the context of hydropower operations. Water levels in reservoirs are influenced by the operator of a hydropower plant, who discharges water through the turbines or stores water in the reservoir, in a fashion that maximizes profit. This rationale governs the seasonal operation scheme and hence determines the water levels within the boundaries of the reservoir's water balance. For progress towards a sustainable development of hydropower, the benefits of this form of electricity generation have to be weighed against the possible detrimental effects of the anthropogenic water level fluctuations. We developed a hydro-economic model that combines an economic optimization function with hydrological estimators of the water balance of a reservoir. Applying this model allowed us to accurately predict water level fluctuations in a reservoir. The hydro-economic model also allowed for scenario calculation of how water levels change with climate change scenarios and with a change in operating scheme of the reservoir (increase in turbine capacity). Further model development will enable the consideration of a variety of additional parameters, such as water withdrawal for irrigation, drinking water supply, or altered energy policies. This advances our ability to sustainably manage water resources that must meet both economic and environmental demands. PMID:25526619

  20. Quantifying Forest Ecosystem Services Tradeoff—Coupled Ecological and Economic Models

    NASA Astrophysics Data System (ADS)

    Haff, P. K.; Ling, P. Y.

    2015-12-01

    Quantification of the effect of carbon-related forestland management activities on ecosystem services is difficult, because knowledge about the dynamics of coupled social-ecological systems is lacking. Different forestland management activities, such as various amount, timing, and methods of harvesting, and natural disturbances events, such as wind and fires, create shocks and uncertainties to the forest carbon dynamics. A spatially explicit model, Landis-ii, was used to model the forest succession for different harvest management scenarios at the Grandfather District, North Carolina. In addition to harvest, the model takes into account of the impact of natural disturbances, such as fire and insects, and species competition. The result shows the storage of carbon in standing biomass and in wood product for each species for each scenario. In this study, optimization is used to analyze the maximum profit and the number of tree species that each forest landowner can gain at different prices of carbon, roundwood, and interest rates for different harvest management scenarios. Time series of roundwood production of different types were estimated using remote sensing data. Econometric analysis is done to understand the possible interaction and relations between the production of different types of roundwood and roundwood prices, which can indicate the possible planting scheme that a forest owner may make. This study quantifies the tradeoffs between carbon sequestration, roundwood production, and forest species diversity not only from an economic perspective, but also takes into account of the forest succession mechanism in a species-diverse region. The resulting economic impact on the forest landowners is likely to influence their future planting decision, which in turn, will influence the species composition and future revenue of the landowners.