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The market for solar energy in the US has grown exponentially due to increased consumer demand resulting from price reduction via economies of scale, technological progress, and a variety of incentives from federal and state governments as well as utility companies. The installation of solar power in Tennessee has more than doubled each year from 2009 to 2011. In this paper, we focus on the behavior of the Tennessee Solar Value Chain (TNSVC) to study the factors that influence growth of solar industry in the state. The impact of existing incentives on the TNSVC is analyzed. The TNSVC is simulated based on inputs from on-site survey to estimate economic impact in terms of the number of jobs added and the tax revenue generated in the state. In addition, a sensitivity analysis for the impact on the TNSVC under different policies those may be adopted by the state of Tennessee in the future is conducted. This paper employs a holistic model which can predict PV installation demand, understand solar value chain capacity, and estimate the revenue generation. It should be noted that the method employed in this study is not unique to the solar energy industry in Tennessee. The data utilized in this study is a combination of public domain information and surveys of suppliers, manufacturers, distributors, and installers. This makes the model in this paper flexible enough to be applied to assess the solar value chain in other state or country. [ABSTRACT FROM AUTHOR]

Abstract: Land use change modeling and simulation is a popular tool in land use planning and policy formulation. However, the outputs of land use change simulation are not always accompanied with information on uncertainty. The goal of this paper is to demonstrate the inherent uncertainty in sprawl simulation, which is attributable to error in the input parameters and to limitations in our understanding of land use systems. To reach this goal, the paper determines sprawl simulation accuracy and uncertainty for a small US metropolitan region as produced by the CLUE-S modeling framework. The model simulates sprawl location in the region accurately, but the certainty of sprawl location projections decreases with time. This uncertainty in the simulation suggests that modelers should report uncertainty with their output over all time horizons so that, on the one hand, land use planners and decision makers do not place too much confidence in any single sprawl simulation (which could lead to unwarranted and expensive urban growth management policies) and, on the other hand, do not place too little confidence in sprawl models (which could have severe socioeconomic and environmental consequences). Thus, reporting uncertainty with simulation output provides planners and decision makers with a platform for more informed land use policy. [Copyright &y& Elsevier]

Abstract: Biofuel production from renewable biomass has experienced increased interest in order to reduce U.S. dependence on imported oil and reduce carbon emissions. Concerns regarding cost efficiency and environmental problems result in significant challenges that hinder the increased biofuel production from renewable biomass. This paper describes the development of a simulation model with an easy-to-use graphical user interface for the biofuel supply chain. The model considers key supply chain activities including biomass harvesting/processing, transportation, and storage. The model uses the delivered feedstock cost, energy consumption, and GHG emissions as system performance criteria. The utility of the supply chain simulation model is demonstrated by considering a biomass supply chain for a biofuel facility in the lower peninsula of Michigan. The results show that the model is a useful tool for supply chain management, including selection of the optimal biofuel facility location, logistics design, inventory management, and information exchange. [Copyright &y& Elsevier]

Abstract: Background: Without diagnosis and antiviral therapy, many patients with chronic hepatitis C infections will develop end-stage liver disease and die from complications. Aims: To evaluate the future impacts of preventive interventions and treatment advances, this paper forecasts a baseline estimate of the future morbidity and mortality of prevalent hepatitis C when left untreated. Methods: We simulated the future disease progression and death for all Americans with prevalent hepatitis C in 2005. To validate the model, we used past seroprevalence to forecast contemporary outcomes. We used the validated model to forecast future cases of end-stage liver disease, transplants, and deaths from 2010 to 2060, and we estimated credible intervals using Monte Carlo simulation. Results: When programmed with past data, our model predicted current levels of hepatitis C outcomes with accuracy between ±1% and 13%. Morbidity and mortality from hepatitis C will rise from 2010 to a peak between the years 2030 and 2035. We forecasted a peak of 38,600 incident cases of end-stage liver disease; 3200 referrals for transplant; and 36,100 deaths. Conclusions: Because current rates of screening and treatment are low, future morbidity and mortality from hepatitis C are likely to increase substantially without public health interventions to increase treatment. [ABSTRACT FROM AUTHOR]

Abstract: Recently, several improvements were made in the DORIS data processing at the IGN/JPL (Institut Geographique National, France; Jet Propulsion Laboratory, California Institute of Technology, USA) analysis center: use of GRACE-derived gravity fields, data preprocessing and station discontinuity detection, etc. This allowed enhanced performances for ground station geodetic positioning (typically 10mm using a week of data), as well as for polar motion (0.5–1.0 mass for daily determination). However, since the loss in 2004 of the DORIS receiver on the TOPEX/Poseidon mission, only four satellites (SPOT-2, SPOT-4, SPOT-5, and ENVISAT) are currently equipped with DORIS receivers. Furthermore, most of them are aging and some have already far exceeded their expected lifetime. The goal of this paper is to analyze how the geodetic performances could be degraded in the future if one or more of these satellites would unfortunately be lost, and to envisage which satellites are currently the most critical in the DORIS geodetic performances. We have reanalyzed 1 year of recent DORIS data (2005), processing all possible combinations of satellite constellation sub-sets. We then compared these results (station coordinates and polar motion) with those obtained in regular data processing when using DORIS data from all four available satellites in 2005. We demonstrate the importance of the SPOT-5 data, equipped with a new type of on-board DORIS receiver. The study also shows some possible weaknesses in our current ENVISAT orbit computations. Fortunately, new DORIS satellites are also expected in the near future (Jason-2, CRYOSAT-2 and AltiKa), which could improve current DORIS-derived geodetic results due to their specific type of orbit (different from the SPOT sun-synchronous orbits) and also to enhanced on-board receivers. [Copyright &y& Elsevier]

Abstract: Reliable estimation of en-route sector capacity is important, especially in high-density traffic areas where controller workload is the driver. En-route sector capacity is commonly estimated using fast-time computer simulation techniques employing models of controller workload. This paper analyses the methodologies employed by a number of countries in Europe and North America, to estimate the capacity of en-route airspace. The data used was obtained from airspace planners and managers. The survey involved interviews using pre-designed questionnaires. The results show that there are two main models used in the simulation of controller workload, and that there is considerable variation both in their application and controller involvement in the capacity estimation process. [Copyright &y& Elsevier]

We describe and validate a simple PV simulation model capable of predicting average PV output as a function of array geometry (slope and azimuth) and location. This simulation tool is used in the Clean Power Estimator––a web-based PV economic evaluation program available in the US and several countries. Results show that the simplified model accurately captures array geometry, seasonal and daily PV output variations when benchmarked against a standard PV simulation program. This paper concludes that web-based Clean Power Estimator simulations have a sound physical basis. [Copyright &y& Elsevier]