1,562 research outputs found

    Additions to Mars Global Reference Atmospheric Model (MARS-GRAM)

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    Three major additions or modifications were made to the Mars Global Reference Atmospheric Model (Mars-GRAM): (1) in addition to the interactive version, a new batch version is available, which uses NAMELIST input, and is completely modular, so that the main driver program can easily be replaced by any calling program, such as a trajectory simulation program; (2) both the interactive and batch versions now have an option for treating local-scale dust storm effects, rather than just the global-scale dust storms in the original Mars-GRAM; and (3) the Zurek wave perturbation model was added, to simulate the effects of tidal perturbations, in addition to the random (mountain wave) perturbation model of the original Mars-GRAM. A minor modification was also made which allows heights to go 'below' local terrain height and return 'realistic' pressure, density, and temperature, and not the surface values, as returned by the original Mars-GRAM. This feature will allow simulations of Mars rover paths which might go into local 'valley' areas which lie below the average height of the present, rather coarse-resolution, terrain height data used by Mars-GRAM. Sample input and output of both the interactive and batch versions of Mars-GRAM are presented

    Complementary Symmetry Nanowire Logic Circuits: Experimental Demonstrations and in Silico Optimizations

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    Complementary symmetry (CS) Boolean logic utilizes both p- and n-type field-effect transistors (FETs) so that an input logic voltage signal will turn one or more p- or n-type FETs on, while turning an equal number of n- or p-type FETs off. The voltage powering the circuit is prevented from having a direct pathway to ground, making the circuit energy efficient. CS circuits are thus attractive for nanowire logic, although they are challenging to implement. CS logic requires a relatively large number of FETs per logic gate, the output logic levels must be fully restored to the input logic voltage level, and the logic gates must exhibit high gain and robust noise margins. We report on CS logic circuits constructed from arrays of 16 nm wide silicon nanowires. Gates up to a complexity of an XOR gate (6 p-FETs and 6 n-FETs) containing multiple nanowires per transistor exhibit signal restoration and can drive other logic gates, implying that large scale logic can be implemented using nanowires. In silico modeling of CS inverters, using experimentally derived look-up tables of individual FET properties, is utilized to provide feedback for optimizing the device fabrication process. Based upon this feedback, CS inverters with a gain approaching 50 and robust noise margins are demonstrated. Single nanowire-based logic gates are also demonstrated, but are found to exhibit significant device-to-device fluctuations

    Archeological Investigations at the Hudnall-Pirtle Site (41RK4) An Early Caddo Mound Center in Northeast Texas

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    The Hudnall-Pirtle site (41RK4) is situated on a large T-1 alluvial terrace of the Sabine River in northern Rusk County in Texas. This area of the state, commonly called Northeast Texas, is part of the Southern Gulf Coastal Plain, a relatively level, sloping plain formed by the pre-Pleistocene embayment of the Gulf of Mexico. From a biogeographical perspective, the site is located in the Oak-Hickory-Pine forest of eastern Texas, otherwise known as the Pineywoods. This area represents the western extension of the southern coniferous forests and is dominated by shortleaf and loblolly pine trees. Hardwood trees, including various oaks, hickory, elm, and gum, are the dominant vegetation in the floodplains of rivers and major creeks in Northeast Texas

    The Stanford Health Assessment Questionnaire: Dimensions and Practical Applications

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    The ability to effectively measure health-related quality-of-life longitudinally is central to describing the impacts of disease, treatment, or other insults, including normal aging, upon the patient. Over the last two decades, assessment of patient health status has undergone a dramatic paradigm shift, evolving from a predominant reliance on biochemical and physical measurements, such as erythrocyte sedimentation rate, lipid profiles, or radiographs, to an emphasis upon health outcomes based on the patient's personal appreciation of their illness. The Health Assessment Questionnaire (HAQ), published in 1980, was among the first instruments based on generic, patient-centered dimensions. The HAQ was designed to represent a model of patient-oriented outcome assessment and has played a major role in many diverse areas such as prediction of successful aging, inversion of the therapeutic pyramid in rheumatoid arthritis (RA), quantification of NSAID gastropathy, development of risk factor models for osteoarthrosis, and examination of mortality risks in RA. Evidenced by its use over the past two decades in diverse settings, the HAQ has established itself as a valuable, effective, and sensitive tool for measurement of health status. It is available in more than 60 languages and is supported by a bibliography of more than 500 references. It has increased the credibility and use of validated self-report measurement techniques as a quantifiable set of hard data endpoints and has contributed to a new appreciation of outcome assessment. In this article, information regarding the HAQ's development, content, dissemination and reference sources for its uses, translations, and validations are provided

    ALCOA #1 (41AN87): A Frankston Phase Settlement along Mound Prairie Creek, Anderson County, Texas

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    The ALCOA #1 (41AN87) site is a Frankston Phase (ca. A.D. 1400-1650) site located on a high alluvial terrace of Mound Prairie Creek, about seven kilometers northeast of Palestine, Texas. Mound Prairie Creek, a perennial stream, flows southeast to east across the county and drains into the Neches River. The site is approximately 10 meters above the Mound Prairie Creek floodplain, and the creek channel is 300 meters to the south. Although the investigations at the site have been rather limited to date, it appears that the ALCOA #1 site is a single component Frankston Phase homestead, or possibly a small hamlet. Other Frankston phase sites are known on Mound Prairie Creek, Hurricane Creek, Walnut Creek, and Brushy Creek, all Neches River tributaries, and the possibility exists that these may be part of a larger related Caddo community and settlement system

    There\u27s A Little Star Shining On You

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    https://digitalcommons.library.umaine.edu/mmb-vp/6511/thumbnail.jp

    Global atmospheric moisture variability

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    Research efforts during FY-88 have focused on completion of several projects relating to analysis of FGGE data during SOP-1 and on expanded studies of global atmospheric moisture. In particular, a revised paper on the relationship between diabatic heating and baroclinicity in the South Pacific Convergence Zone (SPCZ) was submitted. A summary of completed studies on diagnostic convective parameterization was presented at the Satellite Meteorology and Oceanography Convergence last February. These investigations of diabatic heating in the SPCZ have demonstrated the requirement for a more quantitative description of atmospheric moisture. As a result, efforts were directed toward use of passive remote microwave measurements from the Nimbus-7 SMMR and the DOD's Special Sensor Microwave Imager (SSMI/I) as critical sources of moisture data. Activities this year are summarized

    Home Automation Proposal

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    1.1 Objectives The objective for Phase 2 of the Motorola project is to propose a comprehensive home automation system that can be launched in the next one to two years. Currently, there are many entertainment, security, and home control devices on the market but no device that ties these systems together for consumers. The goal is to develop a system that can be easily installed, cost efficient, and able to provide genuine home automation to consumers

    The Measurement of Perceived Social Usefulness

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