21 research outputs found

    MOLECULAR DYNAMICS SIMULATION OF DICARBOXYLIC ACID COATED AQUEOUS AEROSOL: STRUCTURE AND PROCESSING OF WATER VAPOR

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    Low molecular weight dicarboxylic acids constitute a significant fraction of water-soluble organic aerosols in the atmosphere. They have a potential contribution to the formation of cloud condensation nuclei (CCN) and are involved in a series of chemical reactions occurring in atmosphere. In this work, molecular dynamics simulation method was used to probe the structure and the interfacial properties of the dicarboxylic acid coated aqueous aerosol. Low molecular weight dicarboxylic acids of various chain lengths and water solubility were chosen to coat a water droplet consisting of 2440 water molecules. For malonic acid coated aerosol, the surface acid molecules dissolved into the water core and form an ordered structure due to the hydrophobic interactions. For other nanoaerosols coated with low solubility acids, phase separation between water and acid molecules was observed. To study the water processing of the coated aerosols, the water vapor accommodation factors were calculated

    GPU Accelerated Approach to Numerical Linear Algebra and Matrix Analysis with CFD Applications

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    A GPU accelerated approach to numerical linear algebra and matrix analysis with CFD applications is presented. The works objectives are to (1) develop stable and efficient algorithms utilizing multiple NVIDIA GPUs with CUDA to accelerate common matrix computations, (2) optimize these algorithms through CPU/GPU memory allocation, GPU kernel development, CPU/GPU communication, data transfer and bandwidth control to (3) develop parallel CFD applications for Navier Stokes and Lattice Boltzmann analysis methods. Special consideration will be given to performing the linear algebra algorithms under certain matrix types (banded, dense, diagonal, sparse, symmetric and triangular). Benchmarks are performed for all analyses with baseline CPU times being determined to find speed-up factors and measure computational capability of the GPU accelerated algorithms. The GPU implemented algorithms used in this work along with the optimization techniques performed are measured against preexisting work and test matrices available in the NIST Matrix Market. CFD analysis looked to strengthen the assessment of this work by providing a direct engineering application to analysis that would benefit from matrix optimization techniques and accelerated algorithms. Overall, this work desired to develop optimization for selected linear algebra and matrix computations performed with modern GPU architectures and CUDA developer which were applied directly to mathematical and engineering applications through CFD analysis

    Towards quality programming in the automated testing of distributed applications

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    PhD ThesisSoftware testing is a very time-consuming and tedious activity and accounts for over 25% of the cost of software development. In addition to its high cost, manual testing is unpopular and often inconsistently executed. Software Testing Environments (STEs) overcome the deficiencies of manual testing through automating the test process and integrating testing tools to support a wide range of test capabilities. Most prior work on testing is in single-thread applications. This thesis is a contribution to testing of distributed applications, which has not been well explored. To address two crucial issues in testing, when to stop testing and how good the software is after testing, a statistics-based integrated test environment which is an extension of the testing concept in Quality Programming for distributed applications is presented. It provides automatic support for test execution by the Test Driver, test development by the SMAD Tree Editor and the Test Data Generator, test failure analysis by the Test Results Validator and the Test Paths Tracer, test measurement by the Quality Analyst, test management by the Test Manager and test planning by the Modeller. These tools are integrated around a public, shared data model describing the data entities and relationships which are manipulable by these tools. It enables early entry of the test process into the life cycle due to the definition of the quality planning and message-flow routings in the modelling. After well-prepared modelling and requirements specification are undertaken, the test process and the software design and implementation can proceed concurrently. A simple banking application written using Java Remote Method Invocation (RMI) and Java DataBase Connectivity (JDBC) shows the testing process of fitting it into the integrated test environment. The concept of the automated test execution through mobile agents across multiple platforms is also illustrated on this 3-tier client/server application.The National Science Council, Taiwan: The Ministry of National Defense, Taiwan

    Cursorial Adaptations in the Forelimb of the Giant Short-Faced Bear, \u3cem\u3eArctodus simus\u3c/em\u3e, Revealed by Traditional and 3D Landmark Morphometrics

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    The paleobiology of the Pleistocene North American giant short-faced bear, Arctodus simus, has eluded paleontologists for decades. Its more gracile form has led past researchers to myriad intepretations of the locomotion and feeding ecology of this species. While earlier studies have focused on craniodental morphology and simple postcranial indices, it is forelimb morphology that represents a direct compromise between locomotor and foraging behavior. The study here uses traditional and 3D landmark morphometrics to more completely compare the 3-dimensional shape of the major forelimb elements and their muscle attachment sites between A. simus, extant ursids, and other carnivorans. Results herein agree well with previous studies and provide additional evidence for reduced abductor/adductor and supinator/pronator musculature, more restricted parasagittal motion, increased stride length, and lighter and more packed distal elements. Forelimb skeletal morphology therefore supports the hypothesis that A. simmus represents a bear in the early stages of cursorial evolution

    NASA Tech Briefs, January 1996

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    This issue has a special focus on sensors, and include articles on Electronic Components and Circuits, Electronic Systems, Physical Sciences, Materials, Computer Programs, Mechanics, Machinery/Automation, Manufacturing/Fabrication, and Mathematics and Information Science

    Theories of human nature, historical and contemporary : with a personal view

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    https://place.asburyseminary.edu/ecommonsatsdissertations/2169/thumbnail.jp

    Bibliography of Lewis Research Center technical publications announced in 1988

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    This bibliography contains abstracts of the technical reports that resulted from the scientific and engineering work performed and managed by the Lewis Research Center in 1988. Subject, author, and corporate source indexes are also included. All the publications were announced in the 1988 issues of STAR (Scientific and Technical Aerospace Reports) and/or IAA (International Aerospace Abstracts). Included are research reports, journal articles, conference presentations, patents and patent applications, and theses

    Aeronautical engineering: A continuing bibliography with indexes (supplement 254)

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    This bibliography lists 538 reports, articles, and other documents introduced into the NASA scientific and technical information system in June 1990. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics

    Proceedings of the Workshop on Space Telerobotics, volume 1

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    These proceedings report the results of a workshop on space telerobotics, which was held at the Jet Propulsion Laboratory, January 20-22, 1987. Sponsored by the NASA Office of Aeronautics and Space Technology (OAST), the Workshop reflected NASA's interest in developing new telerobotics technology for automating the space systems planned for the 1990s and beyond. The workshop provided a window into NASA telerobotics research, allowing leading researchers in telerobotics to exchange ideas on manipulation, control, system architectures, artificial intelligence, and machine sensing. One of the objectives was to identify important unsolved problems of current interest. The workshop consisted of surveys, tutorials, and contributed papers of both theoretical and practical interest. Several sessions were held on the themes of sensing and perception, control execution, operator interface, planning and reasoning, and system architecture
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