211 research outputs found

    Index to NASA Tech Briefs, 1975

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    This index contains abstracts and four indexes--subject, personal author, originating Center, and Tech Brief number--for 1975 Tech Briefs

    NASA Thesaurus. Volume 1: Hierarchical listing

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    There are 16,713 postable terms and 3,716 nonpostable terms approved for use in the NASA scientific and technical information system in the Hierarchical Listing of the NASA Thesaurus. The generic structure is presented for many terms. The broader term and narrower term relationships are shown in an indented fashion that illustrates the generic structure better than the more widely used BT and NT listings. Related terms are generously applied, thus enhancing the usefulness of the Hierarchical Listing. Greater access to the Hierarchical Listing may be achieved with the collateral use of Volume 2 - Access Vocabulary

    58th Annual Rocky Mountain Conference on Magnetic Resonance

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    Final program, abstracts, and information about the 58th annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Breckenridge, Colorado, July 17-21, 2016

    Radar Sub-surface Sensing for Mapping the Extent of Hydraulic Fractures and for Monitoring Lake Ice and Design of Some Novel Antennas.

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    Hydraulic fracturing, which is a fast-developing well-stimulation technique, has greatly expanded oil and natural gas production in the United States. As the use of hydraulic fracturing has grown, concerns about its environmental impacts have also increased. A sub-surface imaging radar that can detect the extent of hydraulic fractures is highly demanded, but existing radar designs cannot meet the requirement of penetration range on the order of kilometers due to the exorbitant propagation loss in the ground. In the thesis, a medium frequency (MF) band sub-surface radar sensing system is proposed to extend the detectable range to kilometers in rock layers. Algorithms for cross-hole and single-hole configurations are developed based on simulations using point targets and realistic fractured rock models. A super-miniaturized borehole antenna and its feeding network are also designed for this radar system. Also application of imaging radars for sub-surface sensing frozen lakes at Arctic regions is investigated. The scattering mechanism is the key point to understand the radar data and to extract useful information. To explore this topic, a full-wave simulation model to analyze lake ice scattering phenomenology that includes columnar air bubbles is presented. Based on this model, the scattering mechanism from the rough ice/water interface and columnar air bubbles in the ice at C band is addressed and concludes that the roughness at the interface between ice and water is the dominate contributor to backscatter and once the lake is completely frozen the backscatter diminishes significantly. Radar remote sensing systems often require high-performance antennas with special specifications. Besides the borehole antenna for MF band subsurface imaging system, several other antennas are also designed for potential radar systems. Surface-to-borehole setup is an alternative configuration for subsurface imaging system, which requires a miniaturized planar antenna placed on the surface. Such antenna is developed with using artificial electromagnetic materials for size reduction. Furthermore, circularly polarized (CP) waveform can be used for imaging system and omnidirectional CP antenna is needed. Thus, a low-profile planar azimuthal omnidirectional CP antenna with gain of 1dB and bandwidth of 40MHz is designed at 2.4GHz by combining a novel slot antenna and a PIFA antenna.PhDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/120674/1/wujf_1.pd

    Art as integral part of architectural space

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    Thesis (M.S.V.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1993.Includes bibliographical references (leaves 93-97).To integrate art with architecture is the intention of every architect. However, many times other requirements overwhelm artistic potential. There are numerous good, simple examples in the history of architecture where solutions to a variety of often functional requirements have produced exceptional artistic expressions, which in tum have inspired contemporary architectural practice. Pre-industrial architecture not only responded to natural conditions in the environment; it employed all the senses as well ·. in its design of living environments. Today, unfortunately, we rarely find that architects pay attention to sound, smell, water, natural cycles, or, almost unimaginable, to time. Our technology encourages us to separate ourselves from nature. However, this same technology can help us to reintegrate ourselves with nature by designing better living environments. This thesis is, therefore, my way of rethinking design principles that shape the contemporary urban environment and often give it such a cold, formal image. My own philosophy of design is given in the introduction. The rest of the thesis is basically the supportive material, which further illuminates the ideas presented in the introduction. The first part discusses some general trends in contemporary society in order to place my own view of design within a broader context, while the second part lists numerous examples from the history of architecture and art to illustrate and further my philosophy. At the end, in the appendix, I present one of my own projects, the Interactive Water Curtain, to concretely show some of the implications of my aesthetics. Through this work I hope to illustrate the richness of various traditional architectural practices that take advantage of sound, water, time (celestial movement), fragrances, and even living creatures in designing places. I hope this will stimulate creative thinking about using not just visual effects in the design of our living environment, but employing acoustic, olfactory, astronomical, ecological, and kinesthetic design in order to create sensually richer and more pleasant environments where people can live in harmony with nature and other living creatures.by Marta Vahtar.M.S.V.S

    NASA thesaurus. Volume 1: Hierarchical Listing

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    There are over 17,000 postable terms and nearly 4,000 nonpostable terms approved for use in the NASA scientific and technical information system in the Hierarchical Listing of the NASA Thesaurus. The generic structure is presented for many terms. The broader term and narrower term relationships are shown in an indented fashion that illustrates the generic structure better than the more widely used BT and NT listings. Related terms are generously applied, thus enhancing the usefulness of the Hierarchical Listing. Greater access to the Hierarchical Listing may be achieved with the collateral use of Volume 2 - Access Vocabulary and Volume 3 - Definitions

    Feature Papers in Eng

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    This Special Issue is a collection of high-quality reviews and original papers from editorial board members, guest editors, and leading researchers discussing new knowledge or new cutting-edge developments in the field of engineering

    Microelectromechanical Systems and Devices

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    The advances of microelectromechanical systems (MEMS) and devices have been instrumental in the demonstration of new devices and applications, and even in the creation of new fields of research and development: bioMEMS, actuators, microfluidic devices, RF and optical MEMS. Experience indicates a need for MEMS book covering these materials as well as the most important process steps in bulk micro-machining and modeling. We are very pleased to present this book that contains 18 chapters, written by the experts in the field of MEMS. These chapters are groups into four broad sections of BioMEMS Devices, MEMS characterization and micromachining, RF and Optical MEMS, and MEMS based Actuators. The book starts with the emerging field of bioMEMS, including MEMS coil for retinal prostheses, DNA extraction by micro/bio-fluidics devices and acoustic biosensors. MEMS characterization, micromachining, macromodels, RF and Optical MEMS switches are discussed in next sections. The book concludes with the emphasis on MEMS based actuators

    42nd Rocky Mountain Conference on Analytical Chemistry

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    Abstracts from the 42nd annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-sponsored by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Broomfield, Colorado, July 30 - August 3, 2000
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