Aeronautical Engineering: A special bibliography, supplement 60

This bibliography lists 284 reports, articles, and other documents introduced into the NASA scientific and technical information system in July 1975

NASA space station automation: AI-based technology review. Executive summary

Research and Development projects in automation technology for the Space Station are described. Artificial Intelligence (AI) based technologies are planned to enhance crew safety through reduced need for EVA, increase crew productivity through the reduction of routine operations, increase space station autonomy, and augment space station capability through the use of teleoperation and robotics

Updates in Volcanology

Updates in Volcanology - From Volcano Modeling to Volcano Geology is a new book that is based on book chapters offered by various authors to provide a snapshot of current trends in volcanological researches. Following a short Introduction, the book consists of three sections, namely, ''Understanding the Volcano System from Petrology, Geophysics to Large Scale Experiments,'' ''Volcanic Eruptions and Their Impact to the Environment,' and ''Volcanism in the Geological Record.'' These sections collect a total of 13 book chapters demonstrating clearly the research activity in volcanology from geophysical aspects of volcanic systems to their geological framework. Each chapter provides a comprehensive summary of their subject's current research directions. This book hence can equally be useful for students and researchers

Molecular Modeling Applied to CO2-Soluble Molecules and Confined Fluids

CO2 is known to be an environmentally benign solvent. However, its feeble solvent power inhibits its wide use in industrial applications.The ultimate goal of this research is to design and optimize polymers that are highly soluble in CO2. Molecular modeling methods have been usedto analyze the results from experiments and make predictions. We have employed ab initio quantum mechanical methods to investigate interactions between CO2 molecules and polymers. This is done by computing the interactions between CO2 and polymer moieties and important functional groups. These functional groups include ether oxygens, carbonyl oxygens, and fluorines. We have identified several factors that believed to be responsible for CO2-philicity. These factors include multiple site bindings, acidic hydrogens,and geometric considerations. We have designed three possible CO2-soluble molecules based on our calculation results. Our experimental colleagues have synthesized and tested the corresponding polymers to compare with our predictions. Single wall carbon nanotubes have attracted significant scientific interest as adsorption media since their discovery. Fluids confined in nanotubes have significantly different behavior from bulk fluids. We have performed simulations for alkanes adsorbed in the internal and externalsites of carbon nanotubes. The simulation resultsqualitively match the experimental data from temperature programmed desorption. The diffusion coefficients in bulk and confined phases have been calculated. We have also studied the structure andinfrared spectra of water adsorbed in nanotubes over a wide range of temperatures. Our simulation studies have identified the essential physics responsible for a distinctive infrared band observed in recent experiments

Advances in image processing for single-particle analysis by electron cryomicroscopy and challenges ahead

Electron cryomicroscopy (cryo-EM) is essential for the study and functional understanding of non-crystalline macromolecules such as proteins. These molecules cannot be imaged using X-ray crystallography or other popular methods. CryoEM has been successfully used to visualize molecules such as ribosomes, viruses, and ion channels, for example. Obtaining structural models of these at various conformational states leads to insight on how these molecules function. Recent advances in imaging technology have given cryo-EM a scientific rebirth. Because of imaging improvements, image processing and analysis of the resultant images have increased the resolution such that molecular structures can be resolved at the atomic level. Cryo-EM is ripe with stimulating image processing challenges. In this article, we will touch on the most essential in order to build an accurate structural three-dimensional model from noisy projection images. Traditional approaches, such as k-means clustering for class averaging, will be provided as background. With this review, however, we will highlight fresh approaches from new and varied angles for each image processing sub-problem, including a 3D reconstruction method for asymmetric molecules using just two projection images and deep learning algorithms for automated particle picking. Keywords: Cryo-electron microscopy, Single Particle Analysis, Image processing algorithms

Aeronautical engineering: A continuing bibliography with indexes, supplement 100

This bibliography lists 295 reports, articles, and other documents introduced into the NASA Scientific and Technical Information System in August 1978

Astigmatism and Pseudoaccommodation in Pseudophakic Eyes

noAdvanced IOLs with circumferential zones of different power provide pseudoaccommodation. We investigated the potential for power variation with meridian, namely astigmatism, to provide pseudo-accommodation. With appropriate power and axis orientations, acceptable pseudo-accommodation can be achieved