Terrain database interoperability issues in training with distributed interactive simulation

In Distributed Interactive Simulation (DIS), each participating node is responsible for maintaining its own model of the synthetic environment. Problems may arise if significant inconsistencies are allowed to exist between these separate world views, resulting in unrealistic simulation results or negative training, and a corresponding degradation of interoperability in a DIS simulation exercise. In the DIS community, this is known as the simulator terrain database (TDB) correlation problem. This is part of the larger synthetic environment correlation problem in DIS, which includes atmosphere, ocean, space, and a wide variety of dynamic effects, behaviors and models. In this article, we investigate the terrain database correlation problem and the resultant effects on interoperability in DIS systems. The fundamental elements of terrain databases designed for real-time distributed simulation are introduced. A generic data pipeline for terrain database generation systems is developed for the purpose of illustrating causes of the correlation problem and issues of terrain database fidelity. Implications of the problem are discussed, and testing methodologies are recommended for its mitigation. Several statistical methods have been developed to analyze consistency between various elements of the synthetic environment across DIS platforms. Correlation metrics have been formulated for terrain elevations and features. Comparisons and consistency of final rendered images have been addressed. Finally, a suite of software tools that has been developed for interoperability investigations and visual comparison of terrain databases is presented

Towards Commercial Scale Postcombustion Capture of CO 2

Chemical absorption with aqueous amine solvents is the most advanced technology for postcombustion capture (PCC) of CO2 from coal-fired power stations and a number of pilot scale programs are evaluating novel solvents, optimizing energy efficiency, and validating engineering models. This review demonstrates that the development of commercial scale PCC also requires effective solvent management guidelines to ensure minimization of potential technical and environmental risks. Furthermore, the review reveals that while solvent degradation has been identified as a key source of solvent consumption in laboratory scale studies, it has not been validated at pilot scale. Yet this is crucial as solvent degradation products, such as organic acids, can increase corrosivity and reduce the CO2 absorption capacity of the solvent. It also highlights the need for the development of corrosion and solvent reclamation technologies, as well as strategies to minimize emissions of solvent and degradation products, such as ammonia, aldehydes, nitrosamines and nitramines, to the atmosphere from commercial scale PCC. Inevitably, responsible management of aqueous and solid waste will require more serious consideration. This will ultimately require effective waste management practices validated at pilot scale to minimize the likelihood of adverse human and environmental impacts from commercial scale PCC