Science.gov

Sample records for reference designs study

  1. Mars Design Reference Architecture 5.0 Study: Executive Summary

    NASA Technical Reports Server (NTRS)

    Drake, Bret G.

    2008-01-01

    The NASA Mars Design Reference Architecture 5.0 Study seeks to update its long term goals and objective for human exploration missions; flight and surface systems for human missions and supporting infrastructure; operational concept for human and robotic exploration of Mars; key challenges including risk and cost drivers; and, its development schedule options. It additionally seeks to assess strategic linkages between lunar and Mars strategies and develop and understanding of methods for reducing the cost/risk of human Mars missions through investment in research, technology development, and synergy with other exploration plans. Recommendations are made regarding conjunction class (long-stay) missions which are seen as providing the best balance of cost, risk, and performance. Additionally, this study reviews entry, descent, and landing challenges; in-space transportation systems; launch vehicle and Orion assessments; risk and risk mitigation; key driving requirements and challenges; and, lunar linkages.

  2. Mars Aerocapture Studies for the Design Reference Mission

    NASA Technical Reports Server (NTRS)

    Lyne, James Evans; Wercinski, Paul; Walberg, Gerald; Jits, Roman

    1997-01-01

    The recent discovery of possible fossilized microbes in a Martian meteorite sample and the spectacular success of the Mars Pathfinder mission have substantially increased public interest and support for future robotic and manned exploration of Mars. NASA is currently refining a plan known as the Design Reference Mission (DRM) in which the first human landing would occur in 2014 after a series of cargo launches which would place surface systems and an Earth return vehicle at Mars two years prior to the crew's arrival. At each subsequent launch opportunity (which occur approximately every twenty-six months), an additional Earth return vehicle, surface facility and crew would depart for Mars, with each crew employing the systems launched during the previous opportunity. The mission design calls for a long-duration surface stay, rapid crew transits, in-situ manufacture of the Mars ascent propellant, nuclear thermal propulsion for the trans-Mars injection burn, and the use of aerocapture for both the cargo and crew vehicles at Mars.

  3. Interchangeability among reference insulin analogues and their biosimilars: regulatory framework, study design and clinical implications.

    PubMed

    Dowlat, H A; Kuhlmann, M K; Khatami, H; Ampudia-Blasco, F J

    2016-08-01

    Biosimilars are regulated differently from small-molecule generic, chemically derived medicines. The complexity of biological products means that small changes in manufacturing or formulation may result in changes in efficacy and safety of the final product. In the face of this complexity, the regulatory landscape for biosimilars continues to evolve, and global harmonization regarding requirements is currently lacking. It is essential that clinicians and patients are reassured that biosimilars are equally safe and effective as their reference product, and this is particularly important when interchangeability, defined as 'changing one medicine for another one which is expected to achieve the same clinical effect in a given clinical setting in any one patient', is considered. Although the automatic substitution (i.e. substitution without input from the prescribing healthcare provider) of biosimilars for reference products is currently not permitted by the majority of countries, this may change in the future. In order to demonstrate interchangeability between reference products and a biosimilar, more stringent and specific studies of the safety and efficacy of biosimilars are likely to be needed; however, guidance on the design of and the need for any such studies is currently limited. The present article provides an overview of the current regulatory framework around the demonstration of interchangeability with biosimilars, with a specific focus on biosimilar insulin analogues, and details experiences with other biosimilar products. In addition, designs for studies to evaluate interchangeability with a biosimilar insulin analogue product are proposed and a discussion about the implications of interchangeability in clinical practice is included. PMID:27097592

  4. Ilc Cryogenic Systems Reference Design

    NASA Astrophysics Data System (ADS)

    Peterson, T. J.; Geynisman, M.; Klebaner, A.; Parma, V.; Tavian, L.; Theilacker, J.

    2008-03-01

    A Global Design Effort (GDE) began in 2005 to study a TeV scale electron-positron linear accelerator based on superconducting radio-frequency (RF) technology, called the International Linear Collider (ILC). In early 2007, the design effort culminated in a reference design for the ILC, closely based on the earlier TESLA design. The ILC will consist of two 250 GeV linacs, which provide positron-electron collisions for high energy physics research. The particle beams will be accelerated to their final energy in superconducting niobium RF cavities operating at 2 kelvin. At a length of about 12 km each, the main linacs will be the largest cryogenic systems in the ILC. Positron and electron sources, damping rings, and beam delivery systems will also have a large number and variety of other superconducting RF cavities and magnets, which require cooling at liquid helium temperatures. Ten large cryogenic plants with 2 kelvin refrigeration are envisioned to cool the main linacs and the electron and positron sources. Three smaller cryogenic plants will cool the damping rings and beam delivery system components predominately at 4.5 K. This paper describes the cryogenic systems concepts for the ILC.

  5. ILC cryogenic systems reference design

    SciTech Connect

    Peterson, T.J.; Geynisman, M.; Klebaner, A.; Theilacker, J.; Parma, V.; Tavian, L.; /CERN

    2008-01-01

    A Global Design Effort (GDE) began in 2005 to study a TeV scale electron-positron linear accelerator based on superconducting radio-frequency (RF) technology, called the International Linear Collider (ILC). In early 2007, the design effort culminated in a reference design for the ILC, closely based on the earlier TESLA design. The ILC will consist of two 250 GeV linacs, which provide positron-electron collisions for high energy physics research. The particle beams will be accelerated to their final energy in superconducting niobium RF cavities operating at 2 kelvin. At a length of about 12 km each, the main linacs will be the largest cryogenic systems in the ILC. Positron and electron sources, damping rings, and beam delivery systems will also have a large number and variety of other superconducting RF cavities and magnets, which require cooling at liquid helium temperatures. Ten large cryogenic plants with 2 kelvin refrigeration are envisioned to cool the main linacs and the electron and positron sources. Three smaller cryogenic plants will cool the damping rings and beam delivery system components predominately at 4.5 K. This paper describes the cryogenic systems concepts for the ILC.

  6. Design reference missions for the exoplanet starshade (Exo-S) probe-class study

    NASA Astrophysics Data System (ADS)

    Trabert, Rachel; Shaklan, Stuart; Lisman, P. Douglas; Roberge, Aki; Turnbull, Margaret; Domagal-Goldman, Shawn; Stark, Christopher

    2015-09-01

    Exo-S is a direct imaging space-based mission to discover and characterize exoplanets. The mission is comprised of two formation-flying spacecraft - a starlight suppressing starshade and a telescope separated by ~30,000 km. To align the starshade between the target star and telescope, one of the two spacecraft must perform a retargeting slew. This drives the need for a sophisticated program to help optimize this path to maximize target yield within mission constraints such as solar and earth avoidance angles, thrust and fuel limitations, and target scheduling for previously-discovered known giant planets. The Design Reference Mission (DRM) describes the sequence of observations to be performed and estimates the number of planets that will be detected and characterized. It is executed with a Matlab-based tool developed for the Exo-S Study. Here we analyze four case studies: • Case 1: Starshade with a 1.1m dedicated telescope prioritizing the search for earths in the Habitable Zone (HZ). • Case 2: Starshade with a 1.1m dedicated telescope focused on maximizing planet harvest return and characterization. • Case 3: Starshade that rendezvous with a 2.4 m shared telescope prioritizing the search for earths in the HZ. • Case 4: A Rendezvous Earth Finder mission based on a 40-m diameter starshade with a 2.4 m telescope, operating for 4 years, and focused exclusively on detecting Earths in the HZ Previous starshade DRM tools have been reported in the literature, all of them focused on detection and/or characterization of Earth-twins in the habitable zone. This study has taken then next step and focused on total planet harvest including known Gas Giants, Earths in the Habitable Zone and elsewhere, super-earths, sub-Neptunes, and Jupiters. The DRM employs a hierarchical approach: an observation schedule of known radial velocity gas giants, whose availabilities for observation are known form their orbital parameters, forms a "framework" of observation that have a high

  7. The Reference Ability Neural Network Study: motivation, design, and initial feasibility analyses.

    PubMed

    Stern, Yaakov; Habeck, Christian; Steffener, Jason; Barulli, Daniel; Gazes, Yunglin; Razlighi, Qolamreza; Shaked, Danielle; Salthouse, Timothy

    2014-12-01

    We introduce and describe the Reference Ability Neural Network Study and provide initial feasibility data. Based on analyses of large test batteries administered to individuals ranging from young to old, four latent variables, or reference abilities (RAs) that capture the majority of the variance in age-related cognitive change have been identified: episodic memory, fluid reasoning, perceptual speed, and vocabulary. We aim to determine whether spatial fMRI networks can be derived that are uniquely associated with the performance of each reference ability. We plan to image 375 healthy adults (50 per decade from age 20 to 50; 75 per decade from age 50 to 80) while performing a set of 12 cognitive tasks. Data on 174 participants are reported here. Three tasks were grouped a priori into each of the four reference ability domains. We first assessed to what extent both cognitive task scores and activation patterns readily show convergent and discriminant validity, i.e. increased similarity between tasks within the same domain and decreased similarity between tasks between domains, respectively. Block-based time-series analysis of each individual task was conducted for each participant via general linear modeling. We partialled activation common to all tasks out of the imaging data. For both test scores and activation topographies, we then calculated correlations for each of 66 possible pairings of tasks, and compared the magnitude of correlation of tasks within reference ability domains to that of tasks between domains. For the behavioral data, globally there were significantly stronger inter-task correlations within than between domains. When examining individual abilities, 3 of the domains also met these criteria but memory reached only borderline significance. Overall there was greater topographic similarity within reference abilities than between them (p<0.0001), but when examined individually, statistical significance was reached only for episodic memory and

  8. Validation Studies for Numerical Simulations of Flow Phenomena Expected in the Lower Plenum of a Prismatic VHTR Reference Design

    SciTech Connect

    Richard W. Johnson

    2005-09-01

    The final design of the very high temperature reactor (VHTR) of the fourth generation of nuclear power plants (Gen IV) has not yet been established. The VHTR may be either a prismatic (block) or pebble bed type. It may be either gas-cooled or cooled with an as yet unspecified molten salt. However, a conceptual design of a gas-cooled VHTR, based on the General Atomics GT-MHR, does exist and is called the prismatic VHTR reference design, MacDonald et al [2003], General Atomics [1996]. The present validation studies are based on the prismatic VHTR reference design. In the prismatic VHTR reference design, the flow in the lower plenum will be introduced by dozens of turbulent jets issuing into a large crossflow that must negotiate dozens of cylindrical support columns as it flows toward the exit duct of the reactor vessel. The jets will not all be at the same temperature due to the radial variation of power density expected in the core. However, it is important that the coolant be well mixed when it enters the power conversion unit to ensure proper operation and long life of the power conversion machinery. Hence, it is deemed important to be able to accurately model the flow and mixing of the variable temperature coolant in the lower plenum and exit duct. Accurate flow modeling involves determining modeling strategies including the fineness of the grid needed, iterative convergence tolerance, numerical discretization method used, whether the flow is steady or unsteady, and the turbulence model and wall treatment employed. It also involves validation of the computer code and turbulence model against a series of separate and combined flow phenomena and selection of the data used for the validation. The present report describes progress made to date for the task entitled ‘CFD software validation of jets in crossflow’ which was designed to investigate the issues pertaining to the validation process.

  9. Class Size and Educational Achievement: A Review of Methodology with Particular Reference to Study Design.

    ERIC Educational Resources Information Center

    Goldstein, Harvey; Blatchford, Peter

    1998-01-01

    Reviews research into class size effects from a methodological viewpoint, concentrating on various strengths and weaknesses of randomized controlled trials (RCT) and observational studies. Discusses population definitions, causation, and generally sets out criteria for valid inferences from such studies. Illustrates with new findings from data in…

  10. Gathering Design References from Nature

    ERIC Educational Resources Information Center

    Debs, Luciana; Kelley, Todd

    2015-01-01

    Teaching design to middle and high school students can be challenging. One of the first procedures in teaching design is to help students gather information that will be useful in the design phase. An early stage of engineering design as described by Lewis (2005), calls for the designer to establish the state of the art of the problem. During this…

  11. A reference Pelton turbine design

    NASA Astrophysics Data System (ADS)

    Solemslie, B. W.; Dahlhaug, O. G.

    2012-09-01

    The designs of hydraulic turbines are usually close kept corporation secrets. Therefore, the possibility of innovation and co-operation between different academic institutions regarding a specific turbine geometry is difficult. A Ph.D.-project at the Waterpower Laboratory, NTNU, aim to design several model Pelton turbines where all measurements, simulations, the design strategy, design software in addition to the physical model will be available to the public. In the following paper a short description of the methods and the test rig that are to be utilized in the project are described. The design will be based on empirical data and NURBS will be used as the descriptive method for the turbine geometry. In addition CFX and SPH simulations will be included in the design process. Each turbine designed and produced in connection to this project will be based on the experience and knowledge gained from the previous designs. The first design will be based on the philosophy to keep a near constant relative velocity through the bucket.

  12. Benefits of statistical molecular design, covariance analysis, and reference models in QSAR: a case study on acetylcholinesterase.

    PubMed

    Andersson, C David; Hillgren, J Mikael; Lindgren, Cecilia; Qian, Weixing; Akfur, Christine; Berg, Lotta; Ekström, Fredrik; Linusson, Anna

    2015-03-01

    Scientific disciplines such as medicinal- and environmental chemistry, pharmacology, and toxicology deal with the questions related to the effects small organic compounds exhort on biological targets and the compounds' physicochemical properties responsible for these effects. A common strategy in this endeavor is to establish structure-activity relationships (SARs). The aim of this work was to illustrate benefits of performing a statistical molecular design (SMD) and proper statistical analysis of the molecules' properties before SAR and quantitative structure-activity relationship (QSAR) analysis. Our SMD followed by synthesis yielded a set of inhibitors of the enzyme acetylcholinesterase (AChE) that had very few inherent dependencies between the substructures in the molecules. If such dependencies exist, they cause severe errors in SAR interpretation and predictions by QSAR-models, and leave a set of molecules less suitable for future decision-making. In our study, SAR- and QSAR models could show which molecular sub-structures and physicochemical features that were advantageous for the AChE inhibition. Finally, the QSAR model was used for the prediction of the inhibition of AChE by an external prediction set of molecules. The accuracy of these predictions was asserted by statistical significance tests and by comparisons to simple but relevant reference models. PMID:25351962

  13. EBT-P proposed reference design report

    SciTech Connect

    Boch, A.L.

    1980-01-01

    This report describes the proposed reference design for the EBT-P proof-of-principle test device. The device described is a result of broad studies by many participating organizations from industry and from Department of Energy-sponsored fusion research groups, some working together and some in competitive studies, but all with the goal of defining a device at minimum cost and with maximum probability of meeting its goals. This design work is based upon advances in experimental and theoretical understanding of EBT achieved at Oak Ridge National Laboratory. The strategy adopted permits an initial test and validation of the key scaling properties of the ELMO Bumpy Torus concept, with a degree of built-in flexibility to extend the performance parameters toward the condition for containing a fusion reactor plasma. This will lead the way, then, to determination of a later power break-even demonstration and an eventual fusion reactor that can exploit the special high power-density and steady-state properties of the EBT concept.

  14. Crew Transportation System Design Reference Missions

    NASA Technical Reports Server (NTRS)

    Mango, Edward J.

    2015-01-01

    Contains summaries of potential design reference mission goals for systems to transport humans to andfrom low Earth orbit (LEO) for the Commercial Crew Program. The purpose of this document is to describe Design Reference Missions (DRMs) representative of the end-to-end Crew Transportation System (CTS) framework envisioned to successfully execute commercial crew transportation to orbital destinations. The initial CTS architecture will likely be optimized to support NASA crew and NASA-sponsored crew rotation missions to the ISS, but consideration may be given in this design phase to allow for modifications in order to accomplish other commercial missions in the future. With the exception of NASA’s mission to the ISS, the remaining commercial DRMs are notional. Any decision to design or scar the CTS for these additional non-NASA missions is completely up to the Commercial Provider. As NASA’s mission needs evolve over time, this document will be periodically updated to reflect those needs.

  15. MSDS sky reference and preamplifier study

    NASA Technical Reports Server (NTRS)

    Larsen, L.; Stewart, S.; Lambeck, P.

    1974-01-01

    The major goals in re-designing the Multispectral Scanner and Data System (MSDS) sky reference are: (1) to remove the sun-elevation angle and aircraft-attitude angle dependence from the solar-sky illumination measurement, and (2) to obtain data on the optical state of the atmosphere. The present sky reference is dependent on solar elevation and provides essentially no information on important atmospheric parameters. Two sky reference designs were tested. One system is built around a hyperbolic mirror and the reflection approach. A second approach to a sky reference utilizes a fish-eye lens to obtain a 180 deg field of view. A detailed re-design of the present sky reference around the fish-eye approach, even with its limitations, is recommended for the MSDS system. A preamplifier study was undertaken to find ways of improving the noise-equivalent reflectance by reducing the noise level for silicon detector channels on the MSDS.

  16. International linear collider reference design report

    SciTech Connect

    Aarons, G.

    2007-06-22

    The International Linear Collider will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. A proposed electron-positron collider, the ILC will complement the Large Hadron Collider, a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, together unlocking some of the deepest mysteries in the universe. With LHC discoveries pointing the way, the ILC -- a true precision machine -- will provide the missing pieces of the puzzle. Consisting of two linear accelerators that face each other, the ILC will hurl some 10 billion electrons and their anti-particles, positrons, toward each other at nearly the speed of light. Superconducting accelerator cavities operating at temperatures near absolute zero give the particles more and more energy until they smash in a blazing crossfire at the centre of the machine. Stretching approximately 35 kilometres in length, the beams collide 14,000 times every second at extremely high energies -- 500 billion-electron-volts (GeV). Each spectacular collision creates an array of new particles that could answer some of the most fundamental questions of all time. The current baseline design allows for an upgrade to a 50-kilometre, 1 trillion-electron-volt (TeV) machine during the second stage of the project. This reference design provides the first detailed technical snapshot of the proposed future electron-positron collider, defining in detail the technical parameters and components that make up each section of the 31-kilometer long accelerator. The report will guide the development of the worldwide R&D program, motivate international industrial studies and serve as the basis for the final engineering design needed to make an official project proposal later this decade.

  17. Automotive Stirling reference engine design report

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The reference Stirling engine system is described which provides the best possible fuel economy while meeting or exceeding all other program objectives. The system was designed to meet the requirements of a 1984 Pontiac Phoenix (X-body). This design utilizes all new technology that can reasonably be expected to be developed by 1984 and that is judged to provide significant improvement, relative to development risk and cost. Topics covered include: (1) external heat system; (2) hot engine system; (3) cold engine system; (4) engine drive system; (5) power control system and auxiliaries; (6) engine instalation; (7) optimization and vehicle simulation; (8) engine materials; and (9) production cost analysis.

  18. ILC Reference Design Report: Accelerator Executive Summary

    SciTech Connect

    Phinney, Nan; /SLAC

    2007-12-14

    The International Linear Collider (ILC) is a 200-500 GeV center-of-mass high-luminosity linear electron-positron collider, based on 1.3 GHz superconducting radiofrequency (SCRF) accelerating cavities. The use of the SCRF technology was recommended by the International Technology Recommendation Panel (ITRP) in August 2004 [1], and shortly thereafter endorsed by the International Committee for Future Accelerators (ICFA). In an unprecedented milestone in high-energy physics, the many institutes around the world involved in linear collider R&D united in a common effort to produce a global design for the ILC. In November 2004, the 1st International Linear Collider Workshop was held at KEK, Tsukuba, Japan. The workshop was attended by some 200 accelerator physicists from around the world, and paved the way for the 2nd ILC Workshop in August 2005, held at Snowmass, Colorado, USA, where the ILC Global Design Effort (GDE) was officially formed. The GDE membership reflects the global nature of the collaboration, with accelerator experts from all three regions (Americas, Asia and Europe). The first major goal of the GDE was to define the basic parameters and layout of the machine--the Baseline Configuration. This was achieved at the first GDE meeting held at INFN, Frascati, Italy in December 2005 with the creation of the Baseline Configuration Document (BCD). During the next 14 months, the BCD was used as the basis for the detailed design work and value estimate (as described in section 1.6) culminating in the completion of the second major milestone, the publication of the draft ILC Reference Design Report (RDR). The technical design and cost estimate for the ILC is based on two decades of world-wide Linear Collider R&D, beginning with the construction and operation of the SLAC Linear Collider (SLC). The SLC is acknowledged as a proof-of-principle machine for the linear collider concept. The ILC SCRF linac technology was pioneered by the TESLA collaboration*, culminating in

  19. Nuclear Thermal Rocket/Vehicle Characteristics And Sensitivity Trades For NASA's Mars Design Reference Architecture (DRA) 5.0 Study

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2009-01-01

    This paper summarizes Phase I and II analysis results from NASA's recent Mars DRA 5.0 study which re-examined mission, payload and transportation system requirements for a human Mars landing mission in the post-2030 timeframe. Nuclear thermal rocket (NTR) propulsion was again identified as the preferred in-space transportation system over chemical/aerobrake because of its higher specific impulse (I(sub sp)) capability, increased tolerance to payload mass growth and architecture changes, and lower total initial mass in low Earth orbit (IMLEO) which is important for reducing the number of Ares-V heavy lift launches and overall mission cost. DRA 5.0 features a long surface stay (approximately 500 days) split mission using separate cargo and crewed Mars transfer vehicles (MTVs). All vehicles utilize a common core propulsion stage with three 25 klbf composite fuel NERVA-derived NTR engines (T(sub ex) approximately 2650 - 2700 K, p(sub ch) approximately 1000 psia, epsilon approximately 300:1, I(sub sp) approximately 900 - 910 s, engine thrust-toweight ratio approximately 3.43) to perform all primary mission maneuvers. Two cargo flights, utilizing 1-way minimum energy trajectories, pre-deploy a cargo lander to the surface and a habitat lander into a 24-hour elliptical Mars parking orbit where it remains until the arrival of the crewed MTV during the next mission opportunity (approximately 26 months later). The cargo payload elements aerocapture (AC) into Mars orbit and are enclosed within a large triconicshaped aeroshell which functions as payload shroud during launch, then as an aerobrake and thermal protection system during Mars orbit capture and subsequent entry, descent and landing (EDL) on Mars. The all propulsive crewed MTV is a 0-gE vehicle design that utilizes a fast conjunction trajectory that allows approximately 6-7 month 1-way transit times to and from Mars. Four 12.5 kW(sub e) per 125 square meter rectangular photovoltaic arrays provide the crewed MTV with

  20. Reference repository design concept for bedded salt

    SciTech Connect

    Carpenter, D.W.; Martin, R.W.

    1980-10-08

    A reference design concept is presented for the subsurface portions of a nuclear waste repository in bedded salt. General geologic, geotechnical, hydrologic and geochemical data as well as descriptions of the physical systems are provided for use on generic analyses of the pre- and post-sealing performance of repositories in this geologic medium. The geology of bedded salt deposits and the regional and repository horizon stratigraphy are discussed. Structural features of salt beds including discontinuities and dissolution features are presented and their effect on repository performance is discussed. Seismic hazards and the potential effects of earthquakes on underground repositories are presented. The effect on structural stability and worker safety during construction from hydrocarbon and inorganic gases is described. Geohydrologic considerations including regional hydrology, repository scale hydrology and several hydrological failure modes are presented in detail as well as the hydrological considerations that effect repository design. Operational phase performance is discussed with respect to operations, ventilation system, shaft conveyances, waste handling and retrieval systems and receival rates of nuclear waste. Performance analysis of the post sealing period of a nuclear repository is discussed, and parameters to be used in such an analysis are presented along with regulatory constraints. Some judgements are made regarding hydrologic failure scenarios. Finally, the design and licensing process, consistent with the current licensing procedure is described in a format that can be easily understood.

  1. Design and control of energy efficient food drying processes with specific reference to quality; Model development and experimental studies: Moisture movement and dryer design

    SciTech Connect

    Kim, M.; Litchfield, B.; Singh, R.; Liang, H.; Narsimhan, G.; Waananen, K.

    1989-08-01

    The ultimate goal of the project is to develop procedures, techniques, data and other information that will aid in the design of cost effective and energy efficient drying processes that produce high quality foods. This objective has been sought by performing studies to determine the pertinent properties of food products, by developing models to describe the fundamental phenomena of food drying and by testing the models at laboratory scale. Finally, this information is used to develop recommendations and strategies for improved dryer design and control. This volume, Model Development and Experimental Studies, emphasizes the direct and indirect drying processes. An extensive literature review identifies key characteristics of drying models including controlling process resistances, internal mechanisms of moisture movement, structural and thermodynamic assumptions, and methods of model coefficients and material property measurement/determination, model solution, and model validation. Similarities and differences between previous work are noted, and strategies for future drying model development are suggested.

  2. Reference Design Description for a Geologic Repository

    SciTech Connect

    NA

    2000-10-07

    One of the current major national environmental problems is the safe disposal of large quantities of spent nuclear fuel and high-level radioactive waste materials, which are rapidly accumulating throughout the country. These radioactive byproducts are generated as the result of national defense activities and from the generation of electricity by commercial nuclear power plants. At present, spent nuclear fuel is accumulating at over 70 power plant sites distributed throughout 33 states. The safe disposal of these high-level radioactive materials at a central disposal facility is a high national priority. This Reference Design Description explains the current design for a potential geologic repository that may be located at Yucca Mountain in Nevada for the disposal of spent nuclear fuel and high-level radioactive waste materials. This document describes a possible design for the three fundamental parts of a repository: a surface facility, subsurface repository, and waste packaging. It also presents the current conceptual design of the key engineering systems for the final four phases of repository processes: operations, monitoring, closure, and postclosure. In accordance with current law, this design does not include an interim storage option. In addition, this Reference Design Description reviews the expected long-term performance of the potential repository. It describes the natural barrier system which, together with the engineered systems, achieves the repository objectives. This design will protect the public and the environment by allowing the safe disposal of radioactive waste received from government-owned custodial spent fuel sites, high-level radioactive waste sites, and commercial power reactor sites. All design elements meet or exceed applicable regulations governing the disposal of high-level radioactive waste. The design will provide safe disposal of waste materials for at least a 10,000 year period. During this time interval, natural radioactive decay

  3. Designing Optical Mark Forms for Reference Statistics.

    ERIC Educational Resources Information Center

    Hallman, Clark N.

    1981-01-01

    Presents a method for collecting reference desk statistics in machine-readable form using optical marks. Useful data categories are identified, and figures illustrate how data can be recorded for each category. Ten references are listed. (FM)

  4. Moderator design studies for a new neutron reference source based on the D-T fusion reaction

    NASA Astrophysics Data System (ADS)

    Mozhayev, Andrey V.; Piper, Roman K.; Rathbone, Bruce A.; McDonald, Joseph C.

    2016-06-01

    The radioactive isotope Californium-252 (252Cf) is relied upon internationally as a neutron calibration source for ionizing radiation dosimetry because of its high specific activity. The source may be placed within a heavy-water (D2O) moderating sphere to produce a softened spectrum representative of neutron fields common to commercial nuclear power plant environments, among others. Due to termination of the U.S. Department of Energy loan/lease program in 2012, the expense of obtaining 252Cf sources has undergone a significant increase, rendering high output sources largely unattainable. On the other hand, the use of neutron generators in research and industry applications has increased dramatically in recent years. Neutron generators based on deuteriumtritium (D-T) fusion reaction provide high neutron fluence rates and, therefore, could possibly be used as a replacement for 252Cf. To be viable, the 14 MeV D-T output spectrum must be significantly moderated to approximate common workplace environments. This paper presents the results of an effort to select appropriate moderating materials and design a configuration to reshape the primary neutron field toward a spectrum approaching that from a nuclear power plant workplace. A series of Monte-Carlo (MCNP) simulations of single layer high- and low-Z materials are used to identify initial candidate moderators. Candidates are refined through a similar series of simulations involving combinations of 2-5 different materials. The simulated energy distribution using these candidate moderators are rated in comparison to a target spectrum. Other properties, such as fluence preservation and/or enhancement, prompt gamma production and other characteristics are also considered.

  5. Designing a Reference Station for the Information Age.

    ERIC Educational Resources Information Center

    Becket, Margaret; Smith, Henry Bradford

    1986-01-01

    Relates experiences of University of Rochester's main library during complete renovation of the central reference department including the addition of a full-service reference station. Topics covered include planning the reference station, solutions to seven design requirements, increase in staffing and reference questions after one year, and…

  6. A future large-aperture UVOIR space observatory: reference designs

    NASA Astrophysics Data System (ADS)

    Rioux, Norman; Thronson, Harley; Feinberg, Lee; Stahl, H. Philip; Redding, Dave; Jones, Andrew; Sturm, James; Collins, Christine; Liu, Alice

    2015-09-01

    Our joint NASA GSFC/JPL/MSFC/STScI study team has used community-provided science goals to derive mission needs, requirements, and candidate mission architectures for a future large-aperture, non-cryogenic UVOIR space observatory. We describe the feasibility assessment of system thermal and dynamic stability for supporting coronagraphy. The observatory is in a Sun-Earth L2 orbit providing a stable thermal environment and excellent field of regard. Reference designs include a 36-segment 9.2 m aperture telescope that stows within a five meter diameter launch vehicle fairing. Performance needs developed under the study are traceable to a variety of reference designs including options for a monolithic primary mirror.

  7. A Future Large-Aperture UVOIR Space Observatory: Reference Designs

    NASA Technical Reports Server (NTRS)

    Thronson, Harley; Rioux, Norman; Feinberg, Lee; Stahl, H. Philip; Redding, Dave; Jones, Andrew; Sturm, James; Collins, Christine; Liu, Alice

    2015-01-01

    Our joint NASA GSFC/JPL/MSFC/STScI study team has used community-provided science goals to derive mission needs, requirements, and candidate mission architectures for a future large-aperture, non-cryogenic UVOIR space observatory. We describe the feasibility assessment of system thermal and dynamic stability for supporting coronagraphy. The observatory is in a Sun-Earth L2 orbit providing a stable thermal environment and excellent field of regard. Reference designs include a 36-segment 9.2 m aperture telescope that stows within a five meter diameter launch vehicle fairing. Performance needs developed under the study are traceable to a variety of reference designs including options for a monolithic primary mirror.

  8. High Flux Isotope Reactor cold neutron source reference design concept

    SciTech Connect

    Selby, D.L.; Lucas, A.T.; Hyman, C.R.

    1998-05-01

    In February 1995, Oak Ridge National Laboratory`s (ORNL`s) deputy director formed a group to examine the need for upgrades to the High Flux Isotope Reactor (HFIR) system in light of the cancellation of the Advanced neutron Source Project. One of the major findings of this study was that there was an immediate need for the installation of a cold neutron source facility in the HFIR complex. In May 1995, a team was formed to examine the feasibility of retrofitting a liquid hydrogen (LH{sub 2}) cold source facility into an existing HFIR beam tube. The results of this feasibility study indicated that the most practical location for such a cold source was the HB-4 beam tube. This location provides a potential flux environment higher than the Institut Laue-Langevin (ILL) vertical cold source and maximizes the space available for a future cold neutron guide hall expansion. It was determined that this cold neutron beam would be comparable, in cold neutron brightness, to the best facilities in the world, and a decision was made to complete a preconceptual design study with the intention of proceeding with an activity to install a working LH{sub 2} cold source in the HFIR HB-4 beam tube. During the development of the reference design the liquid hydrogen concept was changed to a supercritical hydrogen system for a number of reasons. This report documents the reference supercritical hydrogen design and its performance. The cold source project has been divided into four phases: (1) preconceptual, (2) conceptual design and testing, (3) detailed design and procurement, and (4) installation and operation. This report marks the conclusion of the conceptual design phase and establishes the baseline reference concept.

  9. Mooring Design for the Floating Oscillating Water Column Reference Model.

    SciTech Connect

    Bull, Diana L; Brefort, Dorian

    2014-09-01

    To reduce the price of the reference Backward Bent Duct Buoy (BBDB), a study was done analyzing the effects of reducing the mooring line length, and a new mooring design was developed. It was found that the overall length of the mooring lines could be reduced by 1290 meters, allowing a significant price reduction of the system. In this paper, we will first give a description of the model and the storm environment it will be subject to. We will then give a recommendation for the new mooring system, followed by a discussion of the severe weather simulation results, and an analysis of the conservative and aggressive aspects of the design.

  10. Independent Study Unit on Accelerated Reference Frames

    ERIC Educational Resources Information Center

    Poultney, S. K.

    1973-01-01

    Presents a list of topics, research areas, references, and laboratory equipment which is prepared to facilitate general-science students' understanding of physics aspects in accelerated reference frames after their study of circular motion and Galilean relativity in mechanics. (CC)

  11. The Reference Design for the ILC, Costs, and What's Next

    SciTech Connect

    Barish, Barry

    2007-03-26

    A Reference Design for the International Linear Collider was recently released. The scale of the ILC is such that it must be built by an international collaboration and the design is the culmination of a unique global effort. Through ICFA, a decision was made to base the design on superconducting RF technology and then the Global Design Effort (GDE) was created to coordinate the actual accelerator design toward a construction proposal. The reference design establishes all the features of the machine, and defines both the R&D program and engineering design that will now follow over the next few years.

  12. Richards Barrier LA Reference Design Feature Evaluation

    SciTech Connect

    N.E. Kramer

    1999-11-17

    The Richards Barrier is one of the design features of the repository to be considered for the License Application (LA), Richards was a soil scientist who first described the diversion of moisture between two materials with different hydrologic properties. In this report, a Richards Barrier is a special type of backfill with a fine-grained material (such as sand) overlaying a coarse-grained material (such as gravel). Water that enters an emplacement drift will first encounter the fine-grained material and be transported around the coarse-grained material covering the waste package, thus protecting the waste package from contact with most of the groundwater. The objective of this report is to discuss the benefits and liabilities to the repository by the inclusion of a Richards Barrier type backfill in emplacement drifts. The Richards Barrier can act as a barrier to water flow, can reduce the waste package material dissolution rate, limit mobilization of the radionuclides, and can provide structural protection for the waste package. The scope of this report is to: (1) Analyze the behavior of barrier materials following the intrusion of groundwater for influxes of 1 to 300 mm per year. The report will demonstrate diversion of groundwater intrusions into the barrier over an extended time period when seismic activity and consolidation may cause the potential for liquefaction and settlement of the Richards Barrier. (2) Review the thermal effects of the Richards Barrier on material behavior. (3) Analyze the effect of rockfall on the performance of the Richards Barrier and the depth of the barrier required to protect waste packages under the barrier. (4) Review radiological and heating conditions on placement of multiple layers of the barrier. Subsurface Nuclear Safety personnel will perform calculations to determine the radiation reduction-time relationship and shielding capacity of the barrier. (5) Evaluate the effects of ventilation on cooling of emplacement drifts and

  13. LOXT mirror design study

    NASA Technical Reports Server (NTRS)

    Vanspeybroeck, L.; Antrim, W.; Boyd, D.; Giacconi, R.; Sinnamon, G.; Stille, F.

    1972-01-01

    The final report for the large orbiting X-ray telescope (LOXT) high resolution mirror design study is presented. The following tasks were performed: (1) Generation of a reference and alternate preliminary design for the LOXT high resolution mirror assembly, which will meet the LOXT scientific requirements, and are within the present state of the art of materials and fabrication techniques. (2) Measurement, in X-rays, of the scattering properties of a variety of optical flats, embodying materials, coatings, and polishing techniques which might be applicable to the flight configuration LOXT high resolution mirror. (3) Preparation of a procurement specification for a paraboloid test mirror of the size of the innermost paraboloid of the high resolution mirror assembly, including the design requirements for the reference design evolved from this preliminary design study. The results of the engineering and scientific analysis and the conclusions drawn are presented. The procurement specification for the test mirror is included.

  14. The interstellar heliopause probe technology reference study

    NASA Astrophysics Data System (ADS)

    Lyngvi, A.; Falkner, P.; Peacock, A.

    The interstellar heliopause probe (IHP) is one of ESA's technology reference studies (TRS). The TRS aim to focus the development of strategically important technologies of relevance to future science missions by studying technologically demanding and scientifically interesting missions that are currently not part of the science mission programme. Equipped with a highly integrated payload suite (HIPS), the IHP will perform in situ exploration of the heliopause and the heliospheric interface. The HIPS, which is a standard element in all TRSs, miniaturize payloads through resource reduction by using miniaturized components and sensors, and by sharing common structures and payload functionality. To achieve the scientific requirements of the mission, the spacecraft is to leave the heliosphere as close to the heliosphere nose as possible and reach a distance of 200 AU from the Sun within 25 years. This is possible by using a trajectory with two solar flybys and a solar sail with characteristic acceleration of 1.1 mm/s 2, which corresponds to a 245 × 245 m 2 solar sail and a sail thickness of 1-2 μm. The trajectory facilitates a modest sail design that could potentially be developed in a reasonable timeframe. In this paper, an update to the results of studies being performed on this mission will be given and the current mission baseline and spacecraft design will be described. Furthermore, alternative solar sail systems and enabling technologies will be discussed.

  15. Jewish Studies: A Guide to Reference Sources.

    ERIC Educational Resources Information Center

    McGill Univ., Montreal (Quebec). McLennan Library.

    An annotated bibliography to the reference sources for Jewish Studies in the McLennan Library of McGill University (Canada) is presented. Any titles in Hebrew characters are listed by their transliterated equivalents. There is also a list of relevant Library of Congress Subject Headings. General reference sources listed are: encyclopedias,…

  16. STS ancillary equipment study. User reference book

    NASA Technical Reports Server (NTRS)

    Plough, J. A.

    1977-01-01

    A record of what is currently known about STS ancillary equipment is presented in this user-oriented design so that a potential user may evaluate whether he could use the described ancillary equipment or if he would need to design and fabricate a payload-unique item. References that the user can use to obtain additional details and requirements to aid in his evaluation and decision are included.

  17. Design Reference Missions for Deep-Space Optical Communication

    NASA Astrophysics Data System (ADS)

    Breidenthal, J.; Abraham, D.

    2016-05-01

    We examined the potential, but uncertain, NASA mission portfolio out to a time horizon of 20 years, to identify mission concepts that potentially could benefit from optical communication, considering their communications needs, the environments in which they would operate, and their notional size, weight, and power constraints. A set of 12 design reference missions was selected to represent the full range of potential missions. These design reference missions span the space of potential customer requirements, and encompass the wide range of applications that an optical ground segment might eventually be called upon to serve. The design reference missions encompass a range of orbit types, terminal sizes, and positions in the solar system that reveal the chief system performance variables of an optical ground segment, and may be used to enable assessments of the ability of alternative systems to meet various types of customer needs.

  18. Radioisotope Power Systems Reference Book for Mission Designers and Planners

    NASA Technical Reports Server (NTRS)

    Lee, Young; Bairstow, Brian

    2015-01-01

    The RPS Program's Program Planning and Assessment (PPA) Office commissioned the Mission Analysis team to develop the Radioisotope Power Systems (RPS) Reference Book for Mission Planners and Designers to define a baseline of RPS technology capabilities with specific emphasis on performance parameters and technology readiness. The main objective of this book is to provide RPS technology information that could be utilized by future mission concept studies and concurrent engineering practices. A progress summary from the major branches of RPS technology research provides mission analysis teams with a vital tool for assessing the RPS trade space, and provides concurrent engineering centers with a consistent set of guidelines for RPS performance characteristics. This book will be iterated when substantial new information becomes available to ensure continued relevance, serving as one of the cornerstone products of the RPS PPA Office. This book updates the original 2011 internal document, using data from the relevant publicly released RPS technology references and consultations with RPS technologists. Each performance parameter and RPS product subsection has been reviewed and cleared by at least one subject matter representative. A virtual workshop was held to reach consensus on the scope and contents of the book, and the definitions and assumptions that should be used. The subject matter experts then reviewed and updated the appropriate sections of the book. The RPS Mission Analysis Team then performed further updates and crosschecked the book for consistency. Finally, a second virtual workshop was held to ensure all subject matter experts and stakeholders concurred on the contents.

  19. Human Exploration of Mars Design Reference Architecture 5.0

    NASA Technical Reports Server (NTRS)

    Drake, Bret G.

    2009-01-01

    This document reviews the Design Reference Architecture (DRA) for human exploration of Mars. The DRA represents the current best strategy for human missions. The DRA is not a formal plan, but provides a vision and context to tie current systems and technology developments to potential missions to Mars, and it also serves as a benchmark against which alternative architectures can be measured. The document also reviews the objectives and products of the 2007 study that was to update NASA's human Mars mission reference architecture, assess strategic linkages between lunar and Mars strategies, develop an understanding of methods for reducing cost/risk of human missions through investment in research, technology development and synergy with other exploration plans. There is also a review of the process by which the DRA will continue to be refined. The unique capacities of human exploration is reviewed. The possible goals and objectives of the first three human missions are presented, along with the recommendation that the mission involve a long stay visiting multiple sites.The deployment strategy is outlined and diagrammed including the pre-deployment of the many of the material requirements, and a six crew travel to Mars on a six month trajectory. The predeployment and the Orion crew vehicle are shown. The ground operations requirements are also explained. Also the use of resources found on the surface of Mars is postulated. The Mars surface exploration strategy is reviewed, including the planetary protection processes that are planned. Finally a listing of the key decisions and tenets is posed.

  20. 77 FR 50907 - Airspace Designations; Incorporation by Reference

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-23

    ...This action amends Title 14 Code of Federal Regulations (14 CFR) part 71 relating to airspace designations to reflect the approval by the Director of the Federal Register of the incorporation by reference of FAA Order 7400.9W, Airspace Designations and Reporting Points. This action also explains the procedures the FAA will use to amend the listings of Class A, B, C, D, and E airspace areas;......

  1. Human Exploration of Mars Design Reference Architecture 5.0

    NASA Technical Reports Server (NTRS)

    Drake, Bret G.

    2010-01-01

    This paper provides a summary of the Mars Design Reference Architecture 5.0 (DRA 5.0), which is the latest in a series of NASA Mars reference missions. It provides a vision of one potential approach to human Mars exploration. The reference architecture provides a common framework for future planning of systems concepts, technology development, and operational testing as well as Mars robotic missions, research that is conducted on the International Space Station, and future lunar exploration missions. This summary the Mars DRA 5.0 provides an overview of the overall mission approach, surface strategy and exploration goals, as well as the key systems and challenges for the first three human missions to Mars.

  2. Human Exploration of Mars Design Reference Architecture 5.0

    NASA Technical Reports Server (NTRS)

    Drake, Bret G.; Hoffman, Stephen J.; Beaty, David W.

    2009-01-01

    This paper provides a summary of the 2007 Mars Design Reference Architecture 5.0 (DRA 5.0), which is the latest in a series of NASA Mars reference missions. It provides a vision of one potential approach to human Mars exploration including how Constellation systems can be used. The reference architecture provides a common framework for future planning of systems concepts, technology development, and operational testing as well as Mars robotic missions, research that is conducted on the International Space Station, and future lunar exploration missions. This summary the Mars DRA 5.0 provides an overview of the overall mission approach, surface strategy and exploration goals, as well as the key systems and challenges for the first three human missions to Mars.

  3. Women's Studies: A Guide to Reference Sources.

    ERIC Educational Resources Information Center

    Waiser, Joni, Comp.

    Approximately 125 reference materials on women's studies located in the McClennan Library, McGill University (Montreal), are cited in this annotated bibliography. The bibliography serves as an introduction to social science and humanities materials on women. Library of Congress call numbers are included; dates of publication range from the late…

  4. Basic coaxial mass driver reference design. [electromagnetic lunar launch

    NASA Technical Reports Server (NTRS)

    Kolm, H. H.

    1977-01-01

    The reference design for a basic coaxial mass driver is developed to illustrate the principles and optimization procedures on the basis of numerical integration by programmable pocket calculators. The four inch caliber system uses a single-coil bucket and a single-phase propulsion track with discrete coils, separately energized by capacitors. An actual driver would use multiple-coil buckets and an oscillatory multi-phase drive system. Even the basic, table-top demonstration system should in principle be able to achieve accelerations in the 1,000 m/sq sec range. Current densities of the order of 25 ka/sq cm, continuously achievable only in superconductors, are carried by an ordinary aluminum bucket coil for a short period in order to demonstrate the calculated acceleration. Ultimately the system can be lengthened and provided with a magnetically levitated, superconducting bucket to study levitation dynamics under quasi-steady-state conditions, and to approach lunar escape velocity in an evacuated tube.

  5. Updated reference design of a liquid metal cooled tandem mirror fusion breeder

    SciTech Connect

    Berwald, D.H.; Whitley, R.H.; Garner, J.K.; Gromada, R.J.; McCarville, T.J.; Moir, R.W.; Lee, J.D.; Bandini, B.R.; Fulton, F.J.; Wong, C.P.C.; Maya, I.; Hoot, C.G.; Schultz, K.R.; Miller, L.G.; Beeston, J.M.; Harris, B.L.; Westman, R.A.; Ghoniem, N.M.; Orient, G.; Wolfer, M.; DeVan, J.H.; Torterelli, P.

    1985-09-01

    Detailed studies of key techinical issues for liquid metal cooled fusion breeder (fusion-fission hybrid blankets) have been performed during the period 1983-4. Based upon the results of these studies, the 1982 reference liquid metal cooled tandem mirror fusion breeder blanket design was updated and is described. The updated reference blankets provides increased breeding and lower technological risk in comparison with the original reference blanket. In addition to the blanket design revisions, a plant concept, cost, and fuel cycle economics assessment is provided. The fusion breeder continues to promise an economical source of fissile fuel for the indefinite future.

  6. Reference Model 2: %22Rev 0%22 Rotor Design.

    SciTech Connect

    Barone, Matthew F.; Berg, Jonathan Charles; Griffith, Daniel

    2011-12-01

    The preliminary design for a three-bladed cross-flow rotor for a reference marine hydrokinetic turbine is presented. A rotor performance design code is described, along with modifications to the code to allow prediction of blade support strut drag as well as interference between two counter-rotating rotors. The rotor is designed to operate in a reference site corresponding to a riverine environment. Basic rotor performance and rigid-body loads calculations are performed to size the rotor elements and select the operating speed range. The preliminary design is verified with a simple finite element model that provides estimates of bending stresses during operation. A concept for joining the blades and support struts is developed and analyzed with a separate finite element analysis. Rotor mass, production costs, and annual energy capture are estimated in order to allow calculations of system cost-of-energy. Evaluation Only. Created with Aspose.Pdf.Kit. Copyright 2002-2011 Aspose Pty Ltd Evaluation Only. Created with Aspose.Pdf.Kit. Copyright 2002-2011 Aspose Pty Ltd

  7. Content Analysis of Virtual Reference Data: Reshaping Library Website Design.

    PubMed

    Fan, Suhua Caroline; Welch, Jennifer M

    2016-01-01

    An academic health sciences library wanted to redesign its website to provide better access to health information in the community. Virtual reference data were used to provide information about user searching behavior. This study analyzed three years (2012-2014) of virtual reference data, including e-mail questions, text messaging, and live chat transcripts, to evaluate the library website for redesigning, especially in areas such as the home page, patrons' terminology, and issues prompting patrons to ask for help. A coding system based on information links in the current library website was created to analyze the data. PMID:27391180

  8. Importance of reference gene selection for articular cartilage mechanobiology studies

    PubMed Central

    Al-Sabah, A.; Stadnik, P.; Gilbert, S.J.; Duance, V.C.; Blain, E.J.

    2016-01-01

    Summary Objective Identification of genes differentially expressed in mechano-biological pathways in articular cartilage provides insight into the molecular mechanisms behind initiation and/or progression of osteoarthritis (OA). Quantitative PCR (qPCR) is commonly used to measure gene expression, and is reliant on the use of reference genes for normalisation. Appropriate validation of reference gene stability is imperative for accurate data analysis and interpretation. This study determined in vitro reference gene stability in articular cartilage explants and primary chondrocytes subjected to different compressive loads and tensile strain, respectively. Design The expression of eight commonly used reference genes (18s, ACTB, GAPDH, HPRT1, PPIA, RPL4, SDHA and YWHAZ) was determined by qPCR and data compared using four software packages (comparative delta-Ct method, geNorm, NormFinder and BestKeeper). Calculation of geometric means of the ranked weightings was carried out using RefFinder. Results Appropriate reference gene(s) for normalisation of mechanically-regulated transcript levels in articular cartilage tissue or isolated chondrocytes were dependent on experimental set-up. SDHA, YWHAZ and RPL4 were the most stable genes whilst glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and to a lesser extent Hypoxanthine-guanine phosphoribosyltransferase (HPRT), showed variable expression in response to load, demonstrating their unsuitability in such in vitro studies. The effect of using unstable reference genes to normalise the expression of aggrecan (ACAN) and matrix metalloproteinase 3 (MMP3) resulted in inaccurate quantification of these mechano-sensitive genes and erroneous interpretation/conclusions. Conclusion This study demonstrates that commonly used ‘reference genes’ may be unsuitable for in vitro cartilage chondrocyte mechanobiology studies, reinforcing the principle that careful validation of reference genes is essential prior to each experiment to

  9. Reference Design for a Simple, Durable and Refuelable Interplanetary Spacecraft

    NASA Astrophysics Data System (ADS)

    McConnell, B. S.; Tolley, A. M.

    This article describes a reference design for interplanetary vessels, composed mostly of water, that utilize simplified RF engines for low thrust, long duration propulsion, and hydrogen peroxide for short duration, high thrust burns. The electrothermal engines are designed to heat a wide range of liquid materials, possibly also milled solids or surface dusts. The system emphasizes simple components and processes based on older technologies, many well known since the 1960s, that are understandable, can process a variety of materials, and are easily serviced in flight. The goal is to radically simplify systems and their inter-dependencies, to a point where a reasonably skilled person can learn to operate these vessels, not unlike a sailboat, and to eliminate many design and testing bottlenecks in their construction. The use of water, or hydrogen peroxide generated in situ from that water, is multiply advantageous because it can be used for structure, consumption, irrigation, radiation and debris shielding, and thermal regulation, and thus greatly reduce dead weight by creating an almost fully consumable ship. This also enables the ship to utilize a wide range of in situ materials, and eventually obtain reaction mass from lower gravity sites. The ability to switch between low thrust, constant power and high thrust, short duration maneuvers will enable these ships to travel freely and reach many interesting destinations throughout the solar system. One can think of them as “spacecoaches”, not unlike the prairie schooners of the Old West, which were rugged, serviceable by tradesmen, and easily maintained.

  10. With Reference to Reference Genes: A Systematic Review of Endogenous Controls in Gene Expression Studies

    PubMed Central

    Chapman, Joanne R.; Waldenström, Jonas

    2015-01-01

    The choice of reference genes that are stably expressed amongst treatment groups is a crucial step in real-time quantitative PCR gene expression studies. Recent guidelines have specified that a minimum of two validated reference genes should be used for normalisation. However, a quantitative review of the literature showed that the average number of reference genes used across all studies was 1.2. Thus, the vast majority of studies continue to use a single gene, with β-actin (ACTB) and/or glyceraldehyde 3-phosphate dehydrogenase (GAPDH) being commonly selected in studies of vertebrate gene expression. Few studies (15%) tested a panel of potential reference genes for stability of expression before using them to normalise data. Amongst studies specifically testing reference gene stability, few found ACTB or GAPDH to be optimal, whereby these genes were significantly less likely to be chosen when larger panels of potential reference genes were screened. Fewer reference genes were tested for stability in non-model organisms, presumably owing to a dearth of available primers in less well characterised species. Furthermore, the experimental conditions under which real-time quantitative PCR analyses were conducted had a large influence on the choice of reference genes, whereby different studies of rat brain tissue showed different reference genes to be the most stable. These results highlight the importance of validating the choice of normalising reference genes before conducting gene expression studies. PMID:26555275

  11. NASA'S RPS Design Reference Mission Set for Solar System Exploration

    NASA Astrophysics Data System (ADS)

    Balint, Tibor S.

    2007-01-01

    NASA's 2006 Solar System Exploration (SSE) Strategic Roadmap identified a set of proposed large Flagship, medium New Frontiers and small Discovery class missions, addressing key exploration objectives. These objectives respond to the recommendations by the National Research Council (NRC), reported in the SSE Decadal Survey. The SSE Roadmap is down-selected from an over-subscribed set of missions, called the SSE Design Reference Mission (DRM) set Missions in the Flagship and New Frontiers classes can consider Radioisotope Power Systems (RPSs), while small Discovery class missions are not permitted to use them, due to cost constraints. In line with the SSE DRM set and the SSE Roadmap missions, the RPS DRM set represents a set of missions, which can be enabled or enhanced by RPS technologies. At present, NASA has proposed the development of two new types of RPSs. These are the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG), with static power conversion; and the Stirling Radioisotope Generator (SRG), with dynamic conversion. Advanced RPSs, under consideration for possible development, aim to increase specific power levels. In effect, this would either increase electric power generation for the same amount of fuel, or reduce fuel requirements for the same power output, compared to the proposed MMRTG or SRG. Operating environments could also influence the design, such that an RPS on the proposed Titan Explorer would use smaller fins to minimize heat rejection in the extreme cold environment; while the Venus Mobile Explorer long-lived in-situ mission would require the development of a new RPS, in order to tolerate the extreme hot environment, and to simultaneously provide active cooling to the payload and other electric components. This paper discusses NASA's SSE RPS DRM set, in line with the SSE DRM set. It gives a qualitative assessment regarding the impact of various RPS technology and configuration options on potential mission architectures, which could

  12. NASA's RPS Design Reference Mission Set for Solar System Exploration

    NASA Technical Reports Server (NTRS)

    Balint, Tibor S.

    2007-01-01

    NASA's 2006 Solar System Exploration (SSE) Strategic Roadmap identified a set of proposed large Flagship, medium New Frontiers and small Discovery class missions, addressing key exploration objectives. These objectives respond to the recommendations by the National Research Council (NRC), reported in the SSE Decadal Survey. The SSE Roadmap is down-selected from an over-subscribed set of missions, called the SSE Design Reference Mission (DRM) set. Missions in the Flagship and New Frontiers classes can consider Radioisotope Power Systems (RPSs), while small Discovery class missions are not permitted to use them, due to cost constraints. In line with the SSE DRM set and the SSE Roadmap missions, the RPS DRM set represents a set of missions, which can be enabled or enhanced by RPS technologies. At present, NASA has proposed the development of two new types of RPSs. These are the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG), with static power conversion; and the Stirling Radioisotope Generator (SRG), with dynamic conversion. Advanced RPSs, under consideration for possible development, aim to increase specific power levels. In effect, this would either increase electric power generation for the same amount of fuel, or reduce fuel requirements for the same power output, compared to the proposed MMRTG or SRG. Operating environments could also influence the design, such that an RPS on the proposed Titan Explorer would use smaller fins to minimize heat rejection in the extreme cold environment; while the Venus Mobile Explorer long-lived in-situ mission would require the development of a new RPS, in order to tolerate the extreme hot environment, and to simultaneously provide active cooling to the payload and other electric components. This paper discusses NASA's SSE RPS DRM set, in line with the SSE DRM set. It gives a qualitative assessment regarding the impact of various RPS technology and configuration options on potential mission architectures, which could

  13. Detailed cost estimate of reference residential photovoltaic designs

    SciTech Connect

    Palmer, R.S.; Penasa, D.A.; Thomas, M.G.

    1983-04-01

    This report presents estimated installation costs for four reference residential photovoltaic designs. Installation cost estimates ranged from $1.28 to $2.12/W/sub p/ for arrays installed by union labor (4.1 to 6.07 kW/sub p/-systems), and from $1.22 to $1.83 W/sub p/ for non-union installations. Standoff mounting was found to increase costs from $1.63/W/sub p/ to $2.12/W/sub p/ for a representative case, whereas 25 kWh of battery storage capacity increased installation costs from $1.44/W/sub p/ to $2.08/W/sub p/. Overall system costs (union-based were $6000 to $7000 for a 4.1 kW array in the northeast, to approx. $9000 for a 6.07 kW/sub p/ array in the southwest. This range of installation costs, approx. $1 to $2/W/sub p/ (in 1980 dollars), is representative of current installation costs for residential PV systems. Any future cost reductions are likely to be small and can be accomplished only by optimization of mounting techniques, module efficiencies, and module reliability in toto.

  14. Proposed CTV design reference missions in support of Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Saucillo, Rudy J.; Cirillo, William M.

    1991-01-01

    Use of design reference missions (DRM's) for the cargo transfer vehicle (CTV) in support of Space Station Freedom (SSF) can provide a common baseline for the design and assessment of CTV systems and mission operations. These DRM's may also provide baseline operations scenarios for integrated CTV, Shuttle, and SSF operations. Proposed DRM's for CTV, SSF, and Shuttle operations envisioned during the early post-PMC time frame and continuing through mature, SSF evolutionary operations are described. These proposed DRM's are outlines for detailed mission definition; by treating these DRM's as top-level input for mission design studies, a range of parametric studies for systems/operations may be performed. Shuttle flight design experience, particularly rendezvous flight design, provides an excellent basis for DRM operations studies. To begin analysis of the DRM's, shuttle trajectory design tools were used in single case analysis to define CTV performance requirements. A summary of these results is presented.

  15. Proposed CTV design reference missions in support of Space Station Freedom

    NASA Astrophysics Data System (ADS)

    Saucillo, Rudy J.; Cirillo, William M.

    Use of design reference missions (DRM's) for the cargo transfer vehicle (CTV) in support of Space Station Freedom (SSF) can provide a common baseline for the design and assessment of CTV systems and mission operations. These DRM's may also provide baseline operations scenarios for integrated CTV, Shuttle, and SSF operations. Proposed DRM's for CTV, SSF, and Shuttle operations envisioned during the early post-PMC time frame and continuing through mature, SSF evolutionary operations are described. These proposed DRM's are outlines for detailed mission definition; by treating these DRM's as top-level input for mission design studies, a range of parametric studies for systems/operations may be performed. Shuttle flight design experience, particularly rendezvous flight design, provides an excellent basis for DRM operations studies. To begin analysis of the DRM's, shuttle trajectory design tools were used in single case analysis to define CTV performance requirements. A summary of these results is presented.

  16. Staffing by Design: A Methodology for Staffing Reference

    ERIC Educational Resources Information Center

    Ward, David; Phetteplace, Eric

    2012-01-01

    The growth in number and kind of online reference services has resulted in both new users consulting library research services as well as new patterns of service use. Staffing in-person and virtual reference services desks adequately requires a systematic analysis of patterns of use across service points in order to successfully meet fluctuating…

  17. Large Synoptic Survey Telescope: From Science Drivers to Reference Design

    SciTech Connect

    Ivezic, Z.; Axelrod, T.; Brandt, W.N.; Burke, D.L.; Claver, C.F.; Connolly, A.; Cook, K.H.; Gee, P.; Gilmore, D.K.; Jacoby, S.H.; Jones, R.L.; Kahn, S.M.; Kantor, J.P.; Krabbendam, V.; Lupton, R.H.; Monet, D.G.; Pinto, P.A.; Saha, A.; Schalk, T.L.; Schneider, D.P.; Strauss, Michael A.; /Washington U., Seattle, Astron. Dept. /LSST Corp. /Penn State U., Astron. Astrophys. /KIPAC, Menlo Park /NOAO, Tucson /LLNL, Livermore /UC, Davis /Princeton U., Astrophys. Sci. Dept. /Naval Observ., Flagstaff /Arizona U., Astron. Dept. - Steward Observ. /UC, Santa Cruz /Harvard U. /Johns Hopkins U. /Illinois U., Urbana

    2011-10-14

    In the history of astronomy, major advances in our understanding of the Universe have come from dramatic improvements in our ability to accurately measure astronomical quantities. Aided by rapid progress in information technology, current sky surveys are changing the way we view and study the Universe. Next-generation surveys will maintain this revolutionary progress. We focus here on the most ambitious survey currently planned in the visible band, the Large Synoptic Survey Telescope (LSST). LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: constraining dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. It will be a large, wide-field ground-based system designed to obtain multiple images covering the sky that is visible from Cerro Pachon in Northern Chile. The current baseline design, with an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg{sup 2} field of view, and a 3,200 Megapixel camera, will allow about 10,000 square degrees of sky to be covered using pairs of 15-second exposures in two photometric bands every three nights on average. The system is designed to yield high image quality, as well as superb astrometric and photometric accuracy. The survey area will include 30,000 deg{sup 2} with {delta} < +34.5{sup o}, and will be imaged multiple times in six bands, ugrizy, covering the wavelength range 320-1050 nm. About 90% of the observing time will be devoted to a deep-wide-fast survey mode which will observe a 20,000 deg{sup 2} region about 1000 times in the six bands during the anticipated 10 years of operation. These data will result in databases including 10 billion galaxies and a similar number of stars, and will serve the majority of science programs. The remaining 10% of the observing time will be allocated to special programs such as Very Deep and Very Fast time domain surveys. We describe how the

  18. Large Synoptic Survey Telescope: From Science Drivers To Reference Design

    NASA Astrophysics Data System (ADS)

    Ivezic, Z.; Axelrod, T.; Brandt, W. N.; Burke, D. L.; Claver, C. F.; Connolly, A.; Cook, K. H.; Gee, P.; Gilmore, D. K.; Jacoby, S. H.; Jones, R. L.; Kahn, S. M.; Kantor, J. P.; Krabbendam, V. V.; Lupton, R. H.; Monet, D. G.; Pinto, P. A.; Saha, A.; Schalk, T. L.; Schneider, D. P.; Strauss, M. A.; Stubbs, C. W.; Sweeney, D.; Szalay, A.; Thaler, J. J.; Tyson, J. A.; LSST Collaboration

    2008-06-01

    In the history of astronomy, major advances in our understanding of the Universe have come from dramatic improvements in our ability to accurately measure astronomical quantities. Aided by rapid progress in information technology, current sky surveys are changing the way we view and study the Universe. Next-generation surveys will maintain this revolutionary progress. We focus here on the most ambitious survey currently planned in the visible band, the Large Synoptic Survey Telescope (LSST). LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: constraining dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. It will be a large, wide-field ground-based system designed to obtain multiple images covering the sky that is visible from Cerro Pachón in Northern Chile. The current baseline design, with an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg2 field of view, and a 3,200 Megapixel camera, will allow about 10,000 square degrees of sky to be covered using pairs of 15-second exposures in two photometric bands every three nights on average. The system is designed to yield high image quality, as well as superb astrometric and photometric accuracy. The survey area will include 30,000 deg2 with δ<+34.5°, and will be imaged multiple times in six bands, ugrizy, covering the wavelength range 320--1050 nm. About 90% of the observing time will be devoted to a deep-wide-fast survey mode which will observe a 20,000 deg2 region about 1000 times in the six bands during the anticipated 10 years of operation. These data will result in databases including 10 billion galaxies and a similar number of stars, and will serve the majority of science programs. The remaining 10% of the observing time will be allocated to special programs such as Very Deep and Very Fast time domain surveys. We describe how the LSST science drivers led to

  19. Reference design and operations for deep borehole disposal of high-level radioactive waste.

    SciTech Connect

    Herrick, Courtney Grant; Brady, Patrick Vane; Pye, Steven; Arnold, Bill Walter; Finger, John Travis; Bauer, Stephen J.

    2011-10-01

    A reference design and operational procedures for the disposal of high-level radioactive waste in deep boreholes have been developed and documented. The design and operations are feasible with currently available technology and meet existing safety and anticipated regulatory requirements. Objectives of the reference design include providing a baseline for more detailed technical analyses of system performance and serving as a basis for comparing design alternatives. Numerous factors suggest that deep borehole disposal of high-level radioactive waste is inherently safe. Several lines of evidence indicate that groundwater at depths of several kilometers in continental crystalline basement rocks has long residence times and low velocity. High salinity fluids have limited potential for vertical flow because of density stratification and prevent colloidal transport of radionuclides. Geochemically reducing conditions in the deep subsurface limit the solubility and enhance the retardation of key radionuclides. A non-technical advantage that the deep borehole concept may offer over a repository concept is that of facilitating incremental construction and loading at multiple perhaps regional locations. The disposal borehole would be drilled to a depth of 5,000 m using a telescoping design and would be logged and tested prior to waste emplacement. Waste canisters would be constructed of carbon steel, sealed by welds, and connected into canister strings with high-strength connections. Waste canister strings of about 200 m length would be emplaced in the lower 2,000 m of the fully cased borehole and be separated by bridge and cement plugs. Sealing of the upper part of the borehole would be done with a series of compacted bentonite seals, cement plugs, cement seals, cement plus crushed rock backfill, and bridge plugs. Elements of the reference design meet technical requirements defined in the study. Testing and operational safety assurance requirements are also defined. Overall

  20. An Engineering Design Reference Mission for a Future Large-Aperture UVOIR Space Observatory

    NASA Astrophysics Data System (ADS)

    Thronson, Harley A.; Bolcar, Matthew R.; Clampin, Mark; Crooke, Julie A.; Redding, David; Rioux, Norman; Stahl, H. Philip

    2016-01-01

    From the 2010 NRC Decadal Survey and the NASA Thirty-Year Roadmap, Enduring Quests, Daring Visions, to the recent AURA report, From Cosmic Birth to Living Earths, multiple community assessments have recommended development of a large-aperture UVOIR space observatory capable of achieving a broad range of compelling scientific goals. Of these priority science goals, the most technically challenging is the search for spectroscopic biomarkers in the atmospheres of exoplanets in the solar neighborhood. Here we present an engineering design reference mission (EDRM) for the Advanced Technology Large-Aperture Space Telescope (ATLAST), which was conceived from the start as capable of breakthrough science paired with an emphasis on cost control and cost effectiveness. An EDRM allows the engineering design trade space to be explored in depth to determine what are the most demanding requirements and where there are opportunities for margin against requirements. Our joint NASA GSFC/JPL/MSFC/STScI study team has used community-provided science goals to derive mission needs, requirements, and candidate mission architectures for a future large-aperture, non-cryogenic UVOIR space observatory. The ATLAST observatory is designed to operate at a Sun-Earth L2 orbit, which provides a stable thermal environment and excellent field of regard. Our reference designs have emphasized a serviceable 36-segment 9.2 m aperture telescope that stows within a five-meter diameter launch vehicle fairing. As part of our cost-management effort, this particular reference mission builds upon the engineering design for JWST. Moreover, it is scalable to a variety of launch vehicle fairings. Performance needs developed under the study are traceable to a variety of additional reference designs, including options for a monolithic primary mirror.

  1. An Earth-Moon System Trajectory Design Reference Catalog

    NASA Technical Reports Server (NTRS)

    Folta, David; Bosanac, Natasha; Guzzetti, Davide; Howell, Kathleen C.

    2014-01-01

    As demonstrated by ongoing concept designs and the recent ARTEMIS mission, there is, currently, significant interest in exploiting three-body dynamics in the design of trajectories for both robotic and human missions within the Earth-Moon system. The concept of an interactive and 'dynamic' catalog of potential solutions in the Earth-Moon system is explored within this paper and analyzed as a framework to guide trajectory design. Characterizing and compiling periodic and quasi-periodic solutions that exist in the circular restricted three-body problem may offer faster and more efficient strategies for orbit design, while also delivering innovative mission design parameters for further examination.

  2. An Earth-Moon system trajectory design reference catalog

    NASA Astrophysics Data System (ADS)

    Folta, David C.; Bosanac, Natasha; Guzzetti, Davide; Howell, Kathleen C.

    2015-05-01

    As demonstrated by ongoing concept designs and the recent ARTEMIS mission, there is, currently, significant interest in exploiting three-body dynamics in the design of trajectories for both robotic and human missions within the Earth-Moon system. The concept of an interactive and 'dynamic' catalog of potential solutions in the Earth-Moon system is explored within this paper and analyzed as a framework to guide trajectory design. Characterizing and compiling periodic and quasi-periodic solutions that exist in the circular restricted three-body problem may offer faster and more efficient strategies for orbit design, while also delivering innovative mission design parameters for further examination.

  3. A Study of Librarians' Attitudes Toward the Reference Interview.

    ERIC Educational Resources Information Center

    Deputy, Michele M.

    The reference interview is a critical function of reference work; what a librarian says and does can either build a relationship of trust and satisfaction with patrons, or serve to distance them from librarians. This pilot study examined the attitudes of academic and public librarians toward the reference interview. Librarians from Kent State…

  4. Crew Exploration Vehicle Environmental Control and Life Support Design Reference Missions

    NASA Technical Reports Server (NTRS)

    Lewis, John F.; Anderson, Molly K.; Ewert, Mike S.; Stephan, Ryan A.; Carrasquillo, Robyn L.

    2007-01-01

    In preparation for the contract award of the Crew Exploration Vehicle (CEV), the National Aeronautics and Space Administration (NASA) produced two design reference missions for the vehicle. The design references used teams of engineers across the agency to come up with two configurations. This process helped NASA understand the conflicts and limitations in the CEV design, and investigate options to solve them.

  5. A reference model for model-based design of critical infrastructure protection systems

    NASA Astrophysics Data System (ADS)

    Shin, Young Don; Park, Cheol Young; Lee, Jae-Chon

    2015-05-01

    Today's war field environment is getting versatile as the activities of unconventional wars such as terrorist attacks and cyber-attacks have noticeably increased lately. The damage caused by such unconventional wars has also turned out to be serious particularly if targets are critical infrastructures that are constructed in support of banking and finance, transportation, power, information and communication, government, and so on. The critical infrastructures are usually interconnected to each other and thus are very vulnerable to attack. As such, to ensure the security of critical infrastructures is very important and thus the concept of critical infrastructure protection (CIP) has come. The program to realize the CIP at national level becomes the form of statute in each country. On the other hand, it is also needed to protect each individual critical infrastructure. The objective of this paper is to study on an effort to do so, which can be called the CIP system (CIPS). There could be a variety of ways to design CIPS's. Instead of considering the design of each individual CIPS, a reference model-based approach is taken in this paper. The reference model represents the design of all the CIPS's that have many design elements in common. In addition, the development of the reference model is also carried out using a variety of model diagrams. The modeling language used therein is the systems modeling language (SysML), which was developed and is managed by Object Management Group (OMG) and a de facto standard. Using SysML, the structure and operational concept of the reference model are designed to fulfil the goal of CIPS's, resulting in the block definition and activity diagrams. As a case study, the operational scenario of the nuclear power plant while being attacked by terrorists is studied using the reference model. The effectiveness of the results is also analyzed using multiple analysis models. It is thus expected that the approach taken here has some merits

  6. 7 CFR 801.12 - Design requirements incorporated by reference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Section 801.12 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD ADMINISTRATION (FEDERAL GRAIN INSPECTION SERVICE), DEPARTMENT OF AGRICULTURE OFFICIAL PERFORMANCE REQUIREMENTS FOR GRAIN INSPECTION EQUIPMENT § 801.12 Design requirements...

  7. 7 CFR 801.12 - Design requirements incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Section 801.12 Agriculture Regulations of the Department of Agriculture (Continued) GRAIN INSPECTION, PACKERS AND STOCKYARD ADMINISTRATION (FEDERAL GRAIN INSPECTION SERVICE), DEPARTMENT OF AGRICULTURE OFFICIAL PERFORMANCE REQUIREMENTS FOR GRAIN INSPECTION EQUIPMENT § 801.12 Design requirements...

  8. Multi-point Adjoint-Based Design of Tilt-Rotors in a Noninertial Reference Frame

    NASA Technical Reports Server (NTRS)

    Jones, William T.; Nielsen, Eric J.; Lee-Rausch, Elizabeth M.; Acree, Cecil W.

    2014-01-01

    Optimization of tilt-rotor systems requires the consideration of performance at multiple design points. In the current study, an adjoint-based optimization of a tilt-rotor blade is considered. The optimization seeks to simultaneously maximize the rotorcraft figure of merit in hover and the propulsive efficiency in airplane-mode for a tilt-rotor system. The design is subject to minimum thrust constraints imposed at each design point. The rotor flowfields at each design point are cast as steady-state problems in a noninertial reference frame. Geometric design variables used in the study to control blade shape include: thickness, camber, twist, and taper represented by as many as 123 separate design variables. Performance weighting of each operational mode is considered in the formulation of the composite objective function, and a build up of increasing geometric degrees of freedom is used to isolate the impact of selected design variables. In all cases considered, the resulting designs successfully increase both the hover figure of merit and the airplane-mode propulsive efficiency for a rotor designed with classical techniques.

  9. Factors Influencing Digital Reference Triage: A Think-Aloud Study

    ERIC Educational Resources Information Center

    Pomerantz, Jeffrey

    2004-01-01

    This article describes a think-aloud study conducted to identify factors that influence the decisions made by digital reference "triagers" when performing triage on questions received by digital reference services. This study follows and expands on a Delphi study that identified factors that triagers agreed on after the fact of their performance…

  10. HYBRID SULFUR PROCESS REFERENCE DESIGN AND COST ANALYSIS

    SciTech Connect

    Gorensek, M.; Summers, W.; Boltrunis, C.; Lahoda, E.; Allen, D.; Greyvenstein, R.

    2009-05-12

    This report documents a detailed study to determine the expected efficiency and product costs for producing hydrogen via water-splitting using energy from an advanced nuclear reactor. It was determined that the overall efficiency from nuclear heat to hydrogen is high, and the cost of hydrogen is competitive under a high energy cost scenario. It would require over 40% more nuclear energy to generate an equivalent amount of hydrogen using conventional water-cooled nuclear reactors combined with water electrolysis compared to the proposed plant design described herein. There is a great deal of interest worldwide in reducing dependence on fossil fuels, while also minimizing the impact of the energy sector on global climate change. One potential opportunity to contribute to this effort is to replace the use of fossil fuels for hydrogen production by the use of water-splitting powered by nuclear energy. Hydrogen production is required for fertilizer (e.g. ammonia) production, oil refining, synfuels production, and other important industrial applications. It is typically produced by reacting natural gas, naphtha or coal with steam, which consumes significant amounts of energy and produces carbon dioxide as a byproduct. In the future, hydrogen could also be used as a transportation fuel, replacing petroleum. New processes are being developed that would permit hydrogen to be produced from water using only heat or a combination of heat and electricity produced by advanced, high temperature nuclear reactors. The U.S. Department of Energy (DOE) is developing these processes under a program known as the Nuclear Hydrogen Initiative (NHI). The Republic of South Africa (RSA) also is interested in developing advanced high temperature nuclear reactors and related chemical processes that could produce hydrogen fuel via water-splitting. This report focuses on the analysis of a nuclear hydrogen production system that combines the Pebble Bed Modular Reactor (PBMR), under development by

  11. COS Design Reference Mission andGround System Volume Requirements

    NASA Astrophysics Data System (ADS)

    Keyes, Charles D.; Kutina, Ray; Morse, Jon A.

    1999-04-01

    We describe a scenario for the expected usage of COS that incorporates predicted instrumental capabilities, the COS IDT DRM as currently envisioned, community input, astudy of planned and actual usage of the previous HST spectrographs (FOS, GHRS, andSTIS), and estimates of the time to be allocated to COS by future TACs. From this input we derive, for times of normal and stressed usage, estimates of the expected frequency of COS science- and calibration-related exposures (~12/day), average downlink volume(~600 Mbits/day), archive volume (TBD), and calibration reference file OPUS on-linestorage volume (~1 Gbyte). We also provide summaries of COS instrumental capabilitiesand predicted sensitivities in comparison with those of the other HST spectrographs.

  12. Reference Materials in LIS Instruction: A Delphi Study

    ERIC Educational Resources Information Center

    Rabina, Debbie

    2013-01-01

    This paper presents the results of a Delphi study conducted over a two-month period in 2011. The purpose of the study was to identify reference sources that should be covered in basic reference courses taught in LIS programs in the United States. The Delphi method was selected for its appropriateness in soliciting expert opinions and assessing the…

  13. Design of Low Complexity Model Reference Adaptive Controllers

    NASA Technical Reports Server (NTRS)

    Hanson, Curt; Schaefer, Jacob; Johnson, Marcus; Nguyen, Nhan

    2012-01-01

    Flight research experiments have demonstrated that adaptive flight controls can be an effective technology for improving aircraft safety in the event of failures or damage. However, the nonlinear, timevarying nature of adaptive algorithms continues to challenge traditional methods for the verification and validation testing of safety-critical flight control systems. Increasingly complex adaptive control theories and designs are emerging, but only make testing challenges more difficult. A potential first step toward the acceptance of adaptive flight controllers by aircraft manufacturers, operators, and certification authorities is a very simple design that operates as an augmentation to a non-adaptive baseline controller. Three such controllers were developed as part of a National Aeronautics and Space Administration flight research experiment to determine the appropriate level of complexity required to restore acceptable handling qualities to an aircraft that has suffered failures or damage. The controllers consist of the same basic design, but incorporate incrementally-increasing levels of complexity. Derivations of the controllers and their adaptive parameter update laws are presented along with details of the controllers implementations.

  14. Human Exploration of Mars Design Reference Architecture 5.0, Addendum #2

    NASA Technical Reports Server (NTRS)

    Drake, Bret G. (Editor); Watts Kevin D. (Editor)

    2014-01-01

    This report serves as the second Addendum to NASA-SP-2009-566, "Human Exploration of Mars Design Reference Architecture 5.0." The data and descriptions contained within this Addendum capture some of the key assessments and studies produced since publication of the original document, predominately covering those conducted from 2009 through 2012. The assessments and studies described herein are for the most part independent stand-alone contributions. Effort has not been made to assimilate the findings to provide an updated integrated strategy. That is a recognized future effort. This report should not be viewed as constituting a formal plan for the human exploration of Mars.

  15. Ethics in Reference Service: Codes, Case Studies, or Values?

    ERIC Educational Resources Information Center

    Koster, Gregory E.

    1992-01-01

    Reviews the development of codes of ethics for library reference service and the deficiencies of the code approach; surveys published case studies and hypothetical situations on the issue of unbiased service; and proposes a value-based approach that clarifies the real conflicts and leads to personal decision-making. (34 references) (LRW)

  16. Selected Ethnic and Gender Studies Internet Sources for Reference Use.

    ERIC Educational Resources Information Center

    Pillow, Lisa

    1997-01-01

    Gives a general overview of selected reference resources dealing with ethnic and gender studies available on the Web and presents an annotated list of sources. Studies are broken into African and African American Studies; Asian and Asian American Studies; Latino/Chicano Studies; Native American Studies; Gay, Lesbian, and Bisexual Studies; Men's…

  17. Architectural design proposal for a Martian base to continue NASA Mars Design Reference Mission

    NASA Astrophysics Data System (ADS)

    Kozicki, Janek

    The issue of extraterrestrial bases has recently been a very vivid one. There are orbital stations currently existing and humans will travel to Mars around 2030. They will need stations established there, which will provide them the proper living conditions. Firstly, it might be a small module brought from Earth (e.g. NASA Mars Design Reference Mission module (DRM)), in later stages equivalents of Earth houses may be built from local resources. The goal of this paper is to propose an architectural design for an intermediate stage — for a larger habitable unit transported from Earth. It is inspired by terrestrial portable architecture ideas. A pneumatic structure requires small volume during transportation. However, it provides large habitable space after deployment. It is designed for transport by DRM transportation module and its deployment is considerable easy and brief. An architectural solution analogous to a terrestrial house with a studio and a workshop was assumed. Its form was a result of technical and environmental limitations, and the need for an ergonomic interior. The spatial placement of following zones was carefully considered: residential, agricultural and science, as well as a garage with a workshop, transportation routes, and a control and communication center. The issues of Life Support System, energy, food, water and waste recycling were also discussed. This Martian base was designed to be crewed by a team of eight people to stay on Mars for at least 1.5 year. An Open Plan architectural solution was assumed in pneumatic modules, with a high level of modularity. Walls of standardized sizes with zip-fasteners allow free rearrangement of the interior to adapt to a new situation (e.g. damage of one of the pneumatic modules or a psychological ,,need of a change"). The architectural design focuses on ergonomic and psychological aspects of longer stay in hostile Martian environment. This solution provides Martian crew with a comfortable habitable

  18. Time domain and frequency domain design techniques for model reference adaptive control systems

    NASA Technical Reports Server (NTRS)

    Boland, J. S., III

    1971-01-01

    Some problems associated with the design of model-reference adaptive control systems are considered and solutions to these problems are advanced. The stability of the adapted system is a primary consideration in the development of both the time-domain and the frequency-domain design techniques. Consequentially, the use of Liapunov's direct method forms an integral part of the derivation of the design procedures. The application of sensitivity coefficients to the design of model-reference adaptive control systems is considered. An application of the design techniques is also presented.

  19. Energy Efficient Drivepower : Literature Reference List, Volume 2, Design Engineer`s Supplement.

    SciTech Connect

    Ula, Sadrul.; Birnbaum, Larry E.; Jordan, Don

    1992-01-01

    A large number of information sources in the area of the efficient use of drivepower are listed. The main list is for the general user of drivepower systems. The other list is a supplemental reference list for the design engineer.

  20. Energy Efficient Drivepower : Literature Reference List, Volume 2 Design Engineer's Supplement.

    SciTech Connect

    Ula, Sadrul; Jordan, Don L.; Birnbaum, Larry E.

    1993-01-01

    A large number of information sources in the area of the efficient use of drivepower are listed. The main list is for the general user of drivepower systems. The other list is a supplemental reference list for the design engineer.

  1. Superior Cross-Species Reference Genes: A Blueberry Case Study

    PubMed Central

    Die, Jose V.; Rowland, Lisa J.

    2013-01-01

    The advent of affordable Next Generation Sequencing technologies has had major impact on studies of many crop species, where access to genomic technologies and genome-scale data sets has been extremely limited until now. The recent development of genomic resources in blueberry will enable the application of high throughput gene expression approaches that should relatively quickly increase our understanding of blueberry physiology. These studies, however, require a highly accurate and robust workflow and make necessary the identification of reference genes with high expression stability for correct target gene normalization. To create a set of superior reference genes for blueberry expression analyses, we mined a publicly available transcriptome data set from blueberry for orthologs to a set of Arabidopsis genes that showed the most stable expression in a developmental series. In total, the expression stability of 13 putative reference genes was evaluated by qPCR and a set of new references with high stability values across a developmental series in fruits and floral buds of blueberry were identified. We also demonstrated the need to use at least two, preferably three, reference genes to avoid inconsistencies in results, even when superior reference genes are used. The new references identified here provide a valuable resource for accurate normalization of gene expression in Vaccinium spp. and may be useful for other members of the Ericaceae family as well. PMID:24058469

  2. Cryogenic Propulsion Stage (CPS) Configuration in Support of NASA's Multiple Design Reference Missions (DRMs)

    NASA Technical Reports Server (NTRS)

    Hanna, Stephen G.; Jones, David L.; Creech, Stephen D.; Lawrence, Thomas D.

    2012-01-01

    In support of the National Aeronautics and Space Administration's (NASA) Human Exploration and Operations Mission Directorate (HEOMD), the Space Launch System (SLS) is being designed for safe, affordable, and sustainable human and scientific exploration missions beyond Earth's or-bit (BEO). The SLS Team is tasked with developing a system capable of safely and repeatedly lofting a new fleet of spaceflight vehicles beyond Earth orbit. The Cryogenic Propulsion Stage (CPS) is a key enabler for evolving the SLS capability for BEO missions. This paper reports on the methodology and initial recommendations relative to the CPS, giving a brief retrospective of early studies on this promising propulsion hardware. This paper provides an overview of the requirements development and CPS configuration in support of NASA's multiple Design Reference Missions (DRMs).

  3. Aluminum reference plate, heat sink, and actuator design for an adaptive secondary mirror

    NASA Astrophysics Data System (ADS)

    del Vecchio, Ciro

    1998-09-01

    The design of an adaptive secondary mirror has to satisfy many requirements coming from different fields. The thin mirror must be actuated very precisely with a large bandwidth. The reference plate has to provide a high stability reference for the optical surfaces. The local seeing is not to be degraded by any significant thermal perturbation. In this article, the performances of a configuration with a single aluminum reference plate, that also provides the heat sink, are computed starting from the input power coming from the magnetic actuators, whose magnetic design has been revised.

  4. Time reference in agrammatic aphasia: A cross-linguistic study

    PubMed Central

    Bastiaanse, Roelien; Bamyaci, Elif; Hsu, Chien-Ju; Lee, Jiyeon; Duman, Tuba Yarbay; Thompson, Cynthia K.

    2015-01-01

    It has been shown across several languages that verb inflection is difficult for agrammatic aphasic speakers. In particular, Tense inflection is vulnerable. Several theoretical accounts for this have been posed, for example, a pure syntactic one suggesting that the Tense node is unavailable due to its position in the syntactic tree (Friedmann & Grodzinsky, 1997); one suggesting that the interpretable features of the Tense node are underspecified (Burchert, Swoboda-Moll, & De Bleser, 2005; Wenzlaff & Clahsen, 2004, 2005); and a morphosemantic one, arguing that the diacritic Tense features are affected in agrammatism (Faroqi–Shah & Dickey, 2009; Lee, Milman, & Thompson, 2008). However recent findings (Bastiaanse, 2008) and a reanalysis of some oral production studies (e.g. Lee et al., 2008; Nanousi, Masterson, Druks, & Atkinson, 2006) suggest that both Tense and Aspect are impaired and, most importantly, reference to the past is selectively impaired, both through simple verb forms (such as simple past in English) and through periphrastic verb forms (such as the present perfect, ‘has V-ed’, in English). It will be argued that reference to the past is discourse linked and reference to the present and future is not (Zagona, 2003, in press). In-line with Avrutin’s (2000) theory that suggests discourse linking is impaired in Broca’s aphasia, the PAst DIscourse LInking Hypothesis (PADILIH) has been formulated. Three predictions were tested: (1) patients with agrammatic aphasia are selectively impaired in use of grammatical morphology associated with reference to the past, whereas, inflected forms which refer to the present and future are relatively spared; (2) this impairment is language-independent; and (3) this impairment will occur in both production and comprehension. Agrammatic Chinese, English and Turkish speakers were tested with the Test for Assessing Reference of Time (TART; Bastiaanse, Jonkers, & Thompson, unpublished). Results showed that both the

  5. Study Design for Sequencing Studies.

    PubMed

    Honaas, Loren A; Altman, Naomi S; Krzywinski, Martin

    2016-01-01

    Once a biochemical method has been devised to sample RNA or DNA of interest, sequencing can be used to identify the sampled molecules with high fidelity and low bias. High-throughput sequencing has therefore become the primary data acquisition method for many genomics studies and is being used more and more to address molecular biology questions. By applying principles of statistical experimental design, sequencing experiments can be made more sensitive to the effects under study as well as more biologically sound, hence more replicable. PMID:27008009

  6. Scaffolding Students' Development of Creative Design Skills: A Curriculum Reference Model

    ERIC Educational Resources Information Center

    Lee, Chien-Sing; Kolodner, Janet L.

    2011-01-01

    This paper provides a framework for promoting creative design capabilities in the context of achieving community goals pertaining to sustainable development among high school students. The framework can be used as a reference model to design formal or out-of-school curriculum units in any geographical region. This theme is chosen due to its…

  7. 77 FR 55832 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of a New Equivalent Method

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-11

    ... made under the provisions of 40 CFR part 53, as ] amended on August 31, 2011 (76 FR 54326-54341). The... AGENCY Ambient Air Monitoring Reference and Equivalent Methods: Designation of a New Equivalent Method AGENCY: Environmental Protection Agency. ACTION: Notice of the designation of a new equivalent method...

  8. 77 FR 60985 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-05

    ... 53, as amended on August 31, 2011 (76 FR 54326-54341). The new equivalent methods are automated... AGENCY Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods AGENCY: Environmental Protection Agency. ACTION: Notice of the designation of three new...

  9. Over-Specified Referring Expressions Impair Comprehension: An ERP Study

    ERIC Educational Resources Information Center

    Engelhardt, Paul E.; Demiral, S. Baris; Ferreira, Fernanda

    2011-01-01

    Speakers often include extra information when producing referring expressions, which is inconsistent with the Maxim of Quantity (Grice, 1975). In this study, we investigated how comprehension is affected by unnecessary information. The literature is mixed: some studies have found that extra information facilitates comprehension and others reported…

  10. The WFIRST Interim Design Reference Mission: Capabilities, Constraints, and Open Questions

    NASA Technical Reports Server (NTRS)

    Kruk, Jeffrey W.

    2012-01-01

    The Project Office and Science Definition Team for the Wide-Field Infrared Survey Telescope (WFIRST) are in the midst of a pre-Phase A study to establish a Design Reference Mission (DRM). An Interim report was released in June 2011, with a final report due later in 2012. The predicted performance of the Interim DRM Observatory will be described, including optical quality, observing efficiency, and sensitivity for representative observing scenarios. Observing constraints and other limitations on performance will also be presented, with an emphasis on potential Guest Observer programs. Finally, a brief status update will be provided on open trade studies of interest to the scientific community. The final DRM may differ from the Interim DRM presented here. However, the underlying requirements of the scientific programs are not expected to change, hence the capabilities of the IDRM are likely to be maintained even if the implementation changes in significant ways.

  11. Use of the 4D-Global Reference Atmosphere Model (GRAM) for space shuttle descent design

    NASA Technical Reports Server (NTRS)

    Mccarty, S. M.

    1987-01-01

    The method of using the Global Reference Atmosphere Model (GRAM) mean and dispersed atmospheres to study skipout/overshoot requirements, to characterize mean and worst case vehicle temperatures, study control requirements, and verify design was discussed. Landing sites in these analyses range from 65 N to 30 S, while orbit inclinations vary from 20 deg to 98 deg. The primary concern was that they cannot use as small vertical steps in the reentry calculation as desired because the model predicts anomalously large density shear rates for very small vertical step sizes. The winds predicted by the model are not satisfactory. This is probably because they are geostrophic winds and because the model has an error in the computation of winds in the equatorial regions.

  12. Reference Assessment

    ERIC Educational Resources Information Center

    Bivens-Tatum, Wayne

    2006-01-01

    This article presents interesting articles that explore several different areas of reference assessment, including practical case studies and theoretical articles that address a range of issues such as librarian behavior, patron satisfaction, virtual reference, or evaluation design. They include: (1) "Evaluating the Quality of a Chat Service"…

  13. Development of Integrated Programs for Aerospace-vehicle design (IPAD): Reference design process

    NASA Technical Reports Server (NTRS)

    Meyer, D. D.

    1979-01-01

    The airplane design process and its interfaces with manufacturing and customer operations are documented to be used as criteria for the development of integrated programs for the analysis, design, and testing of aerospace vehicles. Topics cover: design process management, general purpose support requirements, design networks, and technical program elements. Design activity sequences are given for both supersonic and subsonic commercial transports, naval hydrofoils, and military aircraft.

  14. Environmental Reference Series, Earth and Environmental Studies, Part II.

    ERIC Educational Resources Information Center

    Qutub, Musa, Comp.

    Compiled in this reference work are bibliographic citations for books and articles dealing with the earth and environmental studies. Specific categories are geology, oceanography, meteorology, and astronomy. Items are indexed only by title but information about author, source, and date of publication is also noted. (BL)

  15. The Value of Chat Reference Services: A Pilot Study

    ERIC Educational Resources Information Center

    Jacoby, JoAnn; Ward, David; Avery, Susan; Marcyk, Emilia

    2016-01-01

    This article explores student, instructor, and librarian perceptions of chat reference in the context of an introductory composition course. Participants in a mixed-method study responded to an anonymized chat transcript. While student respondents valued speed and efficiency, they were willing to receive instruction and open to questions that…

  16. Environmental Reference Series, Earth and Environment Studies, Part I.

    ERIC Educational Resources Information Center

    Qutub, Musa, Comp.

    Compiled in this reference work are bibliographic citations for books, articles, films, and organizations dealing with the earth and environmental studies. In addition to the above topics of a general nature, specific categories include food, natural resources, origin of life, recycling, and wastes. Items are indexed only by title but information…

  17. Human Health and Performance Aspects of the Mars Design Reference Mission

    NASA Technical Reports Server (NTRS)

    Charles, John B.

    2000-01-01

    This paper will describe the current planning for exploration-class missions, emphasizing the medical, and human factors aspects of such expeditions. The details of mission architecture are still under study, but a typical Mars design reference mission comprises a six-month transit from Earth to Mar, eighteen months in residence on Mars, and a six-month transit back to Earth. Physiological stressors will include environmental factors such as prolonged exposure to radiation, weightlessness in transit, and hypogravity and a toxic atmosphere while on Mars. Psychological stressors will include remoteness from Earth, confinement, and potential interpersonal conflicts, all complicated by circadian alterations. Medical risks including trauma must also be considered. Results of planning for assuring human health and performance will be presented.

  18. Design and operation of a Loran-C time reference station

    NASA Technical Reports Server (NTRS)

    Putkovich, K.

    1974-01-01

    Some of the practical questions that arise when one decides to use Loran-C in a time reference system are explored. An extensive effort is made to provide basic, practical information on establishing and operating a reference station. Four areas were covered: (1) the design, configuration and operational concepts which should be considered prior to establishing and operating a reference station using Loran-C, (2) the options and tradeoffs available regarding capabilities, cost, size, versatility, ease of operation, etc., that are available to the designer, (3) what measurements are made, how they are made and what they mean, and (4) the experience the U.S. Naval Observatory Time Service Division has had in the design and operation of such stations.

  19. Slurry reactor design studies

    SciTech Connect

    Fox, J.M.; Degen, B.D.; Cady, G.; Deslate, F.D.; Summers, R.L. ); Akgerman, A. ); Smith, J.M. )

    1990-06-01

    The objective of these studies was to perform a realistic evaluation of the relative costs of tublar-fixed-bed and slurry reactors for methanol, mixed alcohols and Fischer-Tropsch syntheses under conditions where they would realistically be expected to operate. The slurry Fischer-Tropsch reactor was, therefore, operated at low H{sub 2}/CO ratio on gas directly from a Shell gasifier. The fixed-bed reactor was operated on 2.0 H{sub 2}/CO ratio gas after adjustment by shift and CO{sub 2} removal. Every attempt was made to give each reactor the benefit of its optimum design condition and correlations were developed to extend the models beyond the range of the experimental pilot plant data. For the methanol design, comparisons were made for a recycle plant with high methanol yield, this being the standard design condition. It is recognized that this is not necessarily the optimum application for the slurry reactor, which is being proposed for a once-through operation, coproducing methanol and power. Consideration is also given to the applicability of the slurry reactor to mixed alcohols, based on conditions provided by Lurgi for an Octamix{trademark} plant using their standard tubular-fixed reactor technology. 7 figs., 26 tabs.

  20. Seal design alternatives study

    SciTech Connect

    Van Sambeek, L.L.

    1993-06-01

    This report presents the results from a study of various sealing alternatives for the WIPP sealing system. Overall, the sealing system has the purpose of reducing to the extent possible the potential for fluids (either gas or liquid) from entering or leaving the repository. The sealing system is divided into three subsystems: drift and panel seals within the repository horizon, shaft seals in each of the four shafts, and borehole seals. Alternatives to the baseline configuration for the WIPP seal system design included evaluating different geometries and schedules for seal component installations and the use of different materials for seal components. Order-of-magnitude costs for the various alternatives were prepared as part of the study. Firm recommendations are not presented, but the advantages and disadvantages of the alternatives are discussed. Technical information deficiencies are identified and studies are outlined which can provide required information.

  1. Shuttle communications design study

    NASA Technical Reports Server (NTRS)

    Cartier, D. E.

    1975-01-01

    The design and development of a space shuttle communication system are discussed. The subjects considered include the following: (1) Ku-band satellite relay to shuttle, (2) phased arrays, (3) PN acquisition, (4) quadriplexing of direct link ranging and telemetry, (5) communications blackout on launch and reentry, (6) acquisition after blackout on reentry, (7) wideband communications interface with the Ku-Band rendezvous radar, (8) aeroflight capabilities of the space shuttle, (9) a triple multiplexing scheme equivalent to interplex, and (10) a study of staggered quadriphase for use on the space shuttle.

  2. Integrated technology wing design study

    NASA Technical Reports Server (NTRS)

    Hays, A. P.; Beck, W. E.; Morita, W. H.; Penrose, B. J.; Skarshaug, R. E.; Wainfan, B. S.

    1984-01-01

    The technology development costs and associated benefits in applying advanced technology associated with the design of a new wing for a new or derivative trijet with a capacity for 350 passengers and maximum range of 8519 km, entering service in 1990 were studied. The areas of technology are: (1) airfoil technology; (2) planform parameters; (3) high lift; (4) pitch active control system; (5) all electric systems; (6) E to 3rd power propulsion; (7) airframe/propulsion integration; (8) graphite/epoxy composites; (9) advanced aluminum alloys; (10) titanium alloys; and (11) silicon carbide/aluminum composites. These technologies were applied to the reference aircraft configuration. Payoffs were determined for block fuel reductions and net value of technology. These technologies are ranked for the ratio of net value of technology (NVT) to technology development costs.

  3. BWID System Design Study

    SciTech Connect

    O`Brien, M.C.; Rudin, M.J.; Morrison, J.L.; Richardson, J.G.

    1991-12-31

    The mission of the Buried Waste Integrated Demonstration (BWID) System Design Study is to identify and evaluate technology process options for the cradle-to-grave remediation of Transuranic (TRU)-Contaminated Waste Pits and Trenches buried at the Idaho National Engineering Laboratory (INEL). Emphasis is placed upon evaluating system configuration options and associated functional and operational requirements for retrieving and treating the buried wastes. A Performance-Based Technology Selection Filter was developed to evaluate the identified remediation systems and their enabling technologies based upon system requirements and quantification of technical Comprehensive Environmental Response, Compensation, and Liability (CERCLA) balancing criteria. Remediation systems will also be evaluated with respect to regulatory and institutional acceptance and cost-effectiveness.

  4. BWID System Design Study

    SciTech Connect

    O'Brien, M.C.; Rudin, M.J.; Morrison, J.L.; Richardson, J.G.

    1991-01-01

    The mission of the Buried Waste Integrated Demonstration (BWID) System Design Study is to identify and evaluate technology process options for the cradle-to-grave remediation of Transuranic (TRU)-Contaminated Waste Pits and Trenches buried at the Idaho National Engineering Laboratory (INEL). Emphasis is placed upon evaluating system configuration options and associated functional and operational requirements for retrieving and treating the buried wastes. A Performance-Based Technology Selection Filter was developed to evaluate the identified remediation systems and their enabling technologies based upon system requirements and quantification of technical Comprehensive Environmental Response, Compensation, and Liability (CERCLA) balancing criteria. Remediation systems will also be evaluated with respect to regulatory and institutional acceptance and cost-effectiveness.

  5. Conceptual design optimization study

    NASA Technical Reports Server (NTRS)

    Hollowell, S. J.; Beeman, E. R., II; Hiyama, R. M.

    1990-01-01

    The feasibility of applying multilevel functional decomposition and optimization techniques to conceptual design of advanced fighter aircraft was investigated. Applying the functional decomposition techniques to the conceptual design phase appears to be feasible. The initial implementation of the modified design process will optimize wing design variables. A hybrid approach, combining functional decomposition techniques for generation of aerodynamic and mass properties linear sensitivity derivatives with existing techniques for sizing mission performance and optimization, is proposed.

  6. Application of positive-real functions in hyperstable discrete model-reference adaptive system design.

    NASA Technical Reports Server (NTRS)

    Karmarkar, J. S.

    1972-01-01

    Proposal of an algorithmic procedure, based on mathematical programming methods, to design compensators for hyperstable discrete model-reference adaptive systems (MRAS). The objective of the compensator is to render the MRAS insensitive to initial parameter estimates within a maximized hypercube in the model parameter space.

  7. PERFORMANCE TEST RESULTS AND COMPARATIVE DATA FOR DESIGNATED REFERENCE AND EQUIVALENT METHODS FOR OZONE

    EPA Science Inventory

    Under Part 53 of Title 40 of the Code of Federal Regulations (40 CFR Part 53), the U.S. Environmental Protection Agency designates specific ambient monitoring methods and analyzers as reference or equivalent methods acceptable for use in National Air Monitoring Stations (NAMS), S...

  8. The Role of Virtual Reference in Library Web Site Design: A Qualitative Source for Usage Data

    ERIC Educational Resources Information Center

    Powers, Amanda Clay; Shedd, Julie; Hill, Clay

    2011-01-01

    Gathering qualitative information about usage behavior of library Web sites is a time-consuming process requiring the active participation of patron communities. Libraries that collect virtual reference transcripts, however, hold valuable data regarding how the library Web site is used that could benefit Web designers. An analysis of virtual…

  9. Thermionic Reactor Design Studies

    SciTech Connect

    Schock, Alfred

    1994-06-01

    During the 1960's and early 70's the author performed extensive design studies, analyses, and tests aimed at thermionic reactor concepts that differed significantly from those pursued by other investigators. Those studies, like most others under Atomic Energy Commission (AEC and DOE) and the National Aeronautics and Space Administration (NASA) sponsorship, were terminated in the early 1970's. Some of this work was previously published, but much of it was never made available in the open literature. U.S. interest in thermionic reactors resumed in the early 80's, and was greatly intensified by reports about Soviet ground and flight tests in the late 80's. This recent interest resulted in renewed U.S. thermionic reactor development programs, primarily under Department of Defense (DOD) and Department of Energy (DOE) sponsorship. Since most current investigators have not had an opportunity to study all of the author's previous work, a review of the highlights of that work may be of value to them. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling. Where the author's concepts differed from the later Topaz-2 design was in the relative location of the emitter and the collector. Placing the fueled emitter on the outside of the cylindrical diodes permits much higher axial conductances to reduce ohmic losses in the electrodes of full

  10. Operationalization of a Frame of Reference for Studying Organizational Culture in Middle Schools.

    ERIC Educational Resources Information Center

    Daniel, Larry G.

    A frame of reference for studying culture in middle schools was developed. Items for the Middle School Description Survey (MSDS), which was designed to test elements of the ideal middle school culture, were created based on middle school advocacy literature. The items were conceptually categorized according to E. H. Schein's (1985) cultural…

  11. Mechanical design of the University of Florida Torsion Pendulum for testing the LISA Gravitational Reference Sensor

    NASA Astrophysics Data System (ADS)

    Shelley, Ryan; Chilton, Andrew; Olatunde, Tawio; Ciani, Giacomo; Mueller, Guido; Conklin, John

    2014-03-01

    The Laser Interferometer Space Antenna (LISA) requires free falling test masses, whose acceleration must be below 3 fm/s2/rtHz in the lower part of LISA's frequency band ranging from 0.1 to 100 mHz. Gravitational reference sensors (GRS) house the test masses, shield them from external disturbances, control their orientation, and sense their position at the nm/rtHz level. The GRS torsion pendulum is a laboratory test bed for GRS technology. By decoupling the system of test masses from the gravity of the Earth, it is possible to identify and quantify many sources of noise in the sensor. The mechanical design of the pendulum is critical to the study of the noise sources and the development of new technologies that can improve performance and reduce cost. The suspended test mass is a hollow, gold-coated, aluminum cube which rests inside a gold-coated, aluminum housing with electrodes for sensing and actuating all six degrees of freedom. This poster describes the design, analysis, and assembly of the mechanical subsystems of the UF Torsion Pendulum.

  12. Hepatitis B virus genotype A: design of reference sequences for sub-genotypes.

    PubMed

    Cai, Qun; Zhu, Huilan; Zhang, Yafei; Li, Xu; Zhang, Zhenhua

    2016-06-01

    Genotype A of hepatitis B virus (HBV/A) is widespread and is currently divided into six sub-genotypes. Suitable reference sequences for different sub-genotypes can facilitate research on HBV/A. However, the current reference sequences for this virus are insufficient. In the present work, we retrieved 442 full-length HBV/A genomic sequences from the GenBank database and classified them into sub-genotypes by phylogenetic analysis. By the maximum likelihood method using the MEGA6.0 software, we established the reference sequences for different HBV/A sub-genotypes. Our analyses demonstrated that these reference sequences clustered phylogenetically with known strains, indicating that the reference sequences we established indeed belonged to the right sub-genotypes. HBV/A subtype sequences were selected by geographic origins and grouped as sub-genotypes including A1-South Africa, A2-Europe, A3-Cameroon, and A5-Haiti. Reference sequences of sub-genotypes A1, A2, A3, and A5 were constructed and deposited into GenBank (KP234050-KP234053). By applying phylogenetic analyses, we further determined the time to most recent common ancestor of HBV/A lineages. In conclusion, these newly established reference sequences can provide suitable reference standards for studies on the molecular biology and virology of HBV genotype A. PMID:27002608

  13. HEAO attitude reference design. [for satellite attitude control and determination subsystem

    NASA Technical Reports Server (NTRS)

    Hoffman, D. P.; Mcelroy, T. T.

    1978-01-01

    The paper deals with the precision onboard attitude reference implemented as part of the attitude control and determination subsystem for the three High Energy Astronomy Observatories (HEAO-A, HEAO-B, and HEAO-C) in the HEAO scientific spacecraft program. The first observatory (HEAO-A, designated HEAO-1 when in orbit) was launched successfully into near-earth orbit on August 12, 1977. The HEAO attitude reference, analysis techniques for performance prediction, and flight results from the HEAO-1 observatory during its first months of operation. The HEAO-B design is specifically described and analyzed in terms of gyro processing, kinematic integration, ground update algorithm, and star tracker update algorithm. Attitude reference performance estimates are also discussed. It is shown that the orbital performance of the attitude reference correlates very well with the developmental predictions, thereby validating the analytical techniques used during the development. This validation provides a firm basis from which to extrapolate to other applications and related design concepts.

  14. Geodetic reference systems for long period studies in earth physics

    NASA Technical Reports Server (NTRS)

    Mather, R. S.

    1973-01-01

    A simple system of reference axes is defined for possible use in high precision geodetic studies over long periods of time for programs in earth physics. The proposed system is based on the gravitational and dynamic characteristics of the axis of rotation and the earth's center of mass as defined instantaneously at a given epoch. Techniques are outlined for its continuous representation over time intervals of significance for studies in earth physics. The relationship between the proposed system and the representation of extra-terrestrial objects using the celestial sphere concept is also discussed.

  15. Modular antenna design study

    NASA Technical Reports Server (NTRS)

    Ribble, J. W.

    1981-01-01

    The mechanical design of a modular antenna concept was developed sufficiently to allow manufacture of a working demonstration model of a module, to predict mass properties, and to make performance estimates for antenna reflectors composed of these modules. The primary features of this concept are: (1) each module is an autonomous structural element which can be attached to adjacent modules through a three point connection; (2) the upper surface is a folding hexagonal truss plate mechanism which serves as the supporting structure for a reflective surface; and (3) the entire truss and surface can be folded into a cylindrical envelope in which all truss elements are essentially parallel. The kinematic studies and engineering demonstration model fully verified the deployment kinematics, stowing philosophy, and deployment sequencing for large antenna modules. It was established that such modules can be stowed in packages as small as 25 cm in diameter, using 1.27 cm diameter structural tubes. The development activity indicates that this deployable modular approach towards building large structures in space will support erection of 450 m apertures for operation up to 3 GHz with a single space shuttle flight.

  16. Design Of A SCRAMJET Nozzle With Streamline Tracing Technique And Reference Temerature Methode

    NASA Astrophysics Data System (ADS)

    Riehmer, J.; Gulhan, A.

    2011-05-01

    This study presents a method to find an optimal shape of a three-dimensional supersonic nozzle for a rectangular scramjet combustion chamber with rounded edges by taking into account the skin friction effects. The geometric and flow constraints are defined within the German DFG GRK 1095/2 project and the designed nozzle will be part of a scramjet demonstrator configuration [1]. The nozzle inlet conditions are mean values of the combustion chamber exit conditions with the assumption of a constant specific heat ratio. To generate the shape of the nozzle a streamline tracing technique is applied to an axis-symmetric flow field calculated by the Method of Characteristics (MOC). Skin friction in relatively high pressure supersonic flow from the combustion chamber is very dominant and cannot be neglected in the design process. Therefore the skin friction is calculated using the Reference Temperature Method (RTM) and used for the determination of the thrust and moment vectors. This allows considering viscous effects without boundary layer calculations. With this approach an optimal truncated ideal nozzle contour which yields the geometric constraints can be derived. For the validation of this method comparative calculations have been carried out with the DLR code TAU on an exemplary axis-symmetric supersonic nozzle for different flow conditions. Results showed a good agreement. Finally for the three-dimensional nozzle the analytical solution for the inviscous and viscous case provided comparable data like TAU simulations. Further simplifications of the approach for an efficient three-dimensional nozzle design will be addressed in the paper.

  17. Bias due to composite reference standards in diagnostic accuracy studies.

    PubMed

    Schiller, Ian; van Smeden, Maarten; Hadgu, Alula; Libman, Michael; Reitsma, Johannes B; Dendukuri, Nandini

    2016-04-30

    Composite reference standards (CRSs) have been advocated in diagnostic accuracy studies in the absence of a perfect reference standard. The rationale is that combining results of multiple imperfect tests leads to a more accurate reference than any one test in isolation. Focusing on a CRS that classifies subjects as disease positive if at least one component test is positive, we derive algebraic expressions for sensitivity and specificity of this CRS, sensitivity and specificity of a new (index) test compared with this CRS, as well as the CRS-based prevalence. We use as a motivating example the problem of evaluating a new test for Chlamydia trachomatis, an asymptomatic disease for which no gold-standard test exists. As the number of component tests increases, sensitivity of this CRS increases at the expense specificity, unless all tests have perfect specificity. Therefore, such a CRS can lead to significantly biased accuracy estimates of the index test. The bias depends on disease prevalence and accuracy of the CRS. Further, conditional dependence between the CRS and index test can lead to over-estimation of index test accuracy estimates. This commonly-used CRS combines results from multiple imperfect tests in a way that ignores information and therefore is not guaranteed to improve over a single imperfect reference unless each component test has perfect specificity, and the CRS is conditionally independent of the index test. When these conditions are not met, as in the case of C. trachomatis testing, more realistic statistical models should be researched instead of relying on such CRSs. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26555849

  18. Bulk transfer protocols on satellite link - Study within the OSI reference model

    NASA Astrophysics Data System (ADS)

    Valet, I.

    Since satellite systems, such as TELECOM1 in France, are available for data transmission, new protocols need to be designed to fit the requirements of satellite communication systems and to offer specific facilities to the users. The main features of these new transmission protocols, as they have been specified by NADIR studies, are described. Next, the reasons for choosing to study these protocols within the OSI Reference Model are explained. A detailed study about introducing the protocol mechanisms described above in the OSI Reference model layers is then presented. Different approaches are presented, and the solutions studied are appraised in terms of efficiency, and of conformity to the OSI Reference Model. Finally, the experiments planned by NADIR are mentionned.

  19. Automated Question Triage for Social Reference: A Study of Adopting Decision Factors from Digital Reference

    ERIC Educational Resources Information Center

    Park, Jong Do

    2013-01-01

    The increasing popularity of Social Reference (SR) services has enabled a corresponding growth in the number of users engaging in them as well as in the number of questions submitted to the services. However, the efficiency and quality of the services are being challenged because a large quantity of the questions have not been answered or…

  20. Thermal design and test results for SUNLITE ultra-stable reference cavity

    NASA Technical Reports Server (NTRS)

    Amundsen, Ruth M.

    1991-01-01

    SUNLITE (Stanford University-NASA Laser In-Space Technology Experiment) is a space-based experiment which uses a reference cavity to provide a stable frequency reference for a terahertz laser oscillator. Thermal stability of the cavity is a key factor in attaining a stable narrow-linewidth laser beam. The mount which is used to support and align the cavity will provide thermal isolation from the environment. The baseline requirement for thermal stability of the cavity is 0.025 C/min, but the design is directed toward achieving stability well beyond this requirement to improve the science data gained. A prototype of the cavity mount was fabricated and tested to characterize the thermal performance. The thermal vacuum test involved stable high-resolution temperature measurements and stable baseplate temperature control over long durations. Based on test data, the cavity mount design satisfies the severe requirement for the cavity thermal stability.

  1. Analysis of Improved Reference Design for a Nuclear-Driven High Temperature Electrolysis Hydrogen Production Plant

    SciTech Connect

    Edwin A. Harvego; James E. O'Brien; Michael G. McKellar

    2010-06-01

    The use of High Temperature Electrolysis (HTE) for the efficient production of hydrogen without the greenhouse gas emissions associated with conventional fossil-fuel hydrogen production techniques has been under investigation at the Idaho National Engineering Laboratory (INL) for the last several years. The activities at the INL have included the development, testing and analysis of large numbers of solid oxide electrolysis cells, and the analyses of potential plant designs for large scale production of hydrogen using an advanced Very-High Temperature Reactor (VHTR) to provide the process heat and electricity to drive the electrolysis process. The results of these system analyses, using the UniSim process analysis software, have shown that the HTE process, when coupled to a VHTR capable of operating at reactor outlet temperatures of 800 °C to 950 °C, has the potential to produce the large quantities of hydrogen needed to meet future energy and transportation needs with hydrogen production efficiencies in excess of 50%. In addition, economic analyses performed on the INL reference plant design, optimized to maximize the hydrogen production rate for a 600 MWt VHTR, have shown that a large nuclear-driven HTE hydrogen production plant can to be economically competitive with conventional hydrogen production processes, particularly when the penalties associated with greenhouse gas emissions are considered. The results of this research led to the selection in 2009 of HTE as the preferred concept in the U.S. Department of Energy (DOE) hydrogen technology down-selection process. However, the down-selection process, along with continued technical assessments at the INL, has resulted in a number of proposed modifications and refinements to improve the original INL reference HTE design. These modifications include changes in plant configuration, operating conditions and individual component designs. This paper describes the resulting new INL reference design and presents

  2. Control system design for the large space systems technology reference platform

    NASA Technical Reports Server (NTRS)

    Edmunds, R. S.

    1982-01-01

    Structural models and classical frequency domain control system designs were developed for the large space systems technology (LSST) reference platform which consists of a central bus structure, solar panels, and platform arms on which a variety of experiments may be mounted. It is shown that operation of multiple independently articulated payloads on a single platform presents major problems when subarc second pointing stability is required. Experiment compatibility will be an important operational consideration for systems of this type.

  3. Integrated Design and Production Reference Integration with ArchGenXML V1.00

    SciTech Connect

    Barter, R H

    2004-07-20

    ArchGenXML is a tool that allows easy creation of Zope products through the use of Archetypes. The Integrated Design and Production Reference (IDPR) should be highly configurable in order to meet the needs of a diverse engineering community. Ease of configuration is key to the success of IDPR. The purpose of this paper is to describe a method of using a UML diagram editor to configure IDPR through ArchGenXML and Archetypes.

  4. Coxarthrosis and farm work: a case-referent study.

    PubMed

    Thelin, A; Jansson, B; Jacobsson, B; Ström, H

    1997-11-01

    The purpose of this case-referent study was to analyze the association between coxarthrosis and occupation. The study was performed in a Swedish agricultural county and comprised 269 cases of radiologically verified arthrosis of osteoarthritis (< 3 mm joint space) that were compared to 538 randomly selected controls in the same region, matched for age, sex, and place of residence. Farmers and agricultural workers showed an increased risk of coxarthrosis and the observed risk increased with increasing number of years of farming. Tractor driving and milking were associated with coxarthrosis, whereas no association with other types of machine work could be demonstrated. An association between coxarthrosis and heavy physical work before the age of 16 years was also observed. The results give only limited information on the external causes of coxarthrosis, however. More detailed studies of groups of individuals with coxarthrosis in order to obtain more information about contributing and underlying factors would therefore be valuable. PMID:9327073

  5. Developing Areas Studies: A Guide to Reference Sources.

    ERIC Educational Resources Information Center

    McGill Univ., Montreal (Quebec). McLennan Library.

    This multi-disciplinary annotated bibliography introduces students to reference resources on developing nations. The collection looks at reference works on developing areas of the world as a whole. The reference collection contains many specialized subject bibliographies that may be identified by a keyword search. Sections of the bibliography…

  6. Thermionic Reactor Design Studies

    SciTech Connect

    Schock, Alfred

    1994-08-01

    Paper presented at the 29th IECEC in Monterey, CA in August 1994. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their (thermionic reactor) performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling.

  7. Detailed conceptual designs and economic analyses of a reference Photovoltaic Central Power Station

    NASA Astrophysics Data System (ADS)

    Hughes, D. J.; Heller, B. W.; Stephenson, J. E.

    Detailed conceptual designs and economic analyses of a reference 100MWe Photovoltaic Central Power Station (PV CPS) have been completed. Both flat plate dendritic WEB and point focus fresnel concentrator (100X concentration) arrays were used to develop two individual central station reference designs. Design requirements, detailed drawings and system, subsystem and component specifications form the basis for a plant construction cost estimate. The flat plate array PV CPS costs range from $179M to $483M (1982 U.S. Dollars) for array costs ranging from $1/Wp to $3.50/Wp and power conditioning unit (PCU) costs from $.05/Wp to $.50/Wp. Similar costs for the concentrator PV CPS range from $201M to $505M, respectively. Using representative utility financial parameters, in-house economic models, and a plant performance estimate, levelized busbar energy costs (BBEC) are derived for both flat plate and concentrator designs. BBEC range from $.15/kWh to $.41/kWh for the flat plate PV CPS from $.15/kWh to $.37/kWh for the concentrator PV CPS.

  8. Reference-based benefit design changes consumers' choices and employers' payments for ambulatory surgery.

    PubMed

    Robinson, James C; Brown, Timothy; Whaley, Christopher

    2015-03-01

    Some employers are using reference-based benefit (RBB) designs, also known as "reference-based pricing," to encourage patients to select lower-price ambulatory surgery centers instead of expensive hospital outpatient departments. This article analyzes the impact of such benefit designs for cataract removal surgery from the period 2009-13, using data on 2,347 surgical patients covered by the California Public Employees Retirement System (CalPERS), in comparison to 14,867 patients enrolled in non-CalPERS Anthem Blue Cross plans, which are not covered by RBB. After adjusting for changes in patient case-mix and other factors, the shift to RBB was associated with an increase in ambulatory surgery center use by 8.6 percentage points compared to trends among Anthem enrollees. Total employer and employee payments per procedure, after adjusting for changes in case-mix severity and market factors, declined by 19.7 percent compared with Anthem enrollees not subject to RBB. Consumer cost-sharing requirements increased for CalPERS patients who continued to use hospital outpatient departments but who were not exempted from RBB because of geographic or clinical factors. Reference-based benefits for cataract surgery saved CalPERS $1.3 million in the two years after implementation. PMID:25732491

  9. Advanced turbocharger design study program

    NASA Technical Reports Server (NTRS)

    Culy, D. G.; Heldenbrand, R. W.; Richardson, N. R.

    1984-01-01

    The advanced Turbocharger Design Study consisted of: (1) the evaluation of three advanced engine designs to determine their turbocharging requirements, and of technologies applicable to advanced turbocharger designs; (2) trade-off studies to define a turbocharger conceptual design and select the engine with the most representative requirements for turbocharging; (3) the preparation of a turbocharger conceptual design for the Curtiss Wright RC2-32 engine selected in the trade-off studies; and (4) the assessment of market impact and the preparation of a technology demonstration plan for the advanced turbocharger.

  10. Planetary benchmarks. [structural design criteria for radar reference devices on planetary surfaces

    NASA Technical Reports Server (NTRS)

    Uphoff, C.; Staehle, R.; Kobrick, M.; Jurgens, R.; Price, H.; Slade, M.; Sonnabend, D.

    1978-01-01

    Design criteria and technology requirements for a system of radar reference devices to be fixed to the surfaces of the inner planets are discussed. Offshoot applications include the use of radar corner reflectors as landing beacons on the planetary surfaces and some deep space applications that may yield a greatly enhanced knowledge of the gravitational and electromagnetic structure of the solar system. Passive retroreflectors with dimensions of about 4 meters and weighing about 10 kg are feasible for use with orbiting radar at Venus and Mars. Earth-based observation of passive reflectors, however, would require very large and complex structures to be delivered to the surfaces. For Earth-based measurements, surface transponders offer a distinct advantage in accuracy over passive reflectors. A conceptual design for a high temperature transponder is presented. The design appears feasible for the Venus surface using existing electronics and power components.

  11. A standard reference for chamber testing of material VOC emissions: Design principle and performance

    NASA Astrophysics Data System (ADS)

    Wei, Wenjuan; Zhang, Yinping; Xiong, Jianyin; Li, Mu

    2012-02-01

    Environmental chambers are widely used to test formaldehyde and other volatile organic compound (VOC) emissions from indoor materials and furniture. However, there is a lack of a proven method to assess the precision of the test results of the chamber system. In this paper, we describe a new standard reference, LIFE (liquid-inner tube diffusion-film-emission), to address this problem. This reference has the following salient features: (1) Constant emission rate, with less than 3.0% change with an ambient airflow speed (>0.014 m/s) at furniture emission range (0.1-1.0 mg/m 3 in a 30 m 3 chamber with air change rate of 1/h) under standard chamber test conditions as specified by ISO 16000-9 (23 °C, 50% RH); (2) Long duration of emissions, on the order of 1000 h; (3) Easy to store, apply and maintain. The design principle and criteria of the LIFE reference are presented. An analytical model and dimensionless analysis were applied to optimize the factors influencing the emission rate, and experiments were conducted to validate the analytical results. In addition, the equivalent emission parameters of the reference, i.e., the initial emittable concentration, the diffusion coefficient and the partition coefficient, were determined through a three-parameter optimizing regression. This can then be used to check the reliability of a chamber method for testing these three parameters. The developed standard reference should prove useful for calibrating chamber systems for indoor material/furniture VOC emissions tests.

  12. Requirements and design reference mission for the WFIRST/AFTA coronagraph instrument

    NASA Astrophysics Data System (ADS)

    Demers, Richard T.; Dekens, Frank; Calvet, Rob; Chang, Zensheu; Effinger, Robert; Ek, Eric; Hovland, Larry; Jones, Laura; Loc, Anthony; Nemati, Bijan; Noecker, Charley; Neville, Timothy; Pham, Hung; Rud, Mike; Tang, Hong; Villalvazo, Juan

    2015-09-01

    The WFIRST-AFTA coronagraph instrument takes advantage of AFTAs 2.4-meter aperture to provide novel exoplanet imaging science at approximately the same instrument cost as an Explorer mission. The AFTA coronagraph also matures direct imaging technologies to high TRL for an Exo-Earth Imager in the next decade. The coronagraph Design Reference Mission (DRM) optical design is based on the highly successful High Contrast Imaging Testbed (HCIT), with modifications to accommodate the AFTA telescope design, service-ability, volume constraints, and the addition of an Integral Field Spectrograph (IFS). In order to optimally satisfy the three science objectives of planet imaging, planet spectral characterization and dust debris imaging, the coronagraph is designed to operate in two different modes: Hybrid Lyot Coronagraph or Shaped Pupil Coronagraph. Active mechanisms change pupil masks, focal plane masks, Lyot masks, and bandpass filters to shift between modes. A single optical beam train can thus operate alternatively as two different coronagraph architectures. Structural Thermal Optical Performance (STOP) analysis predicts the instrument contrast with the Low Order Wave Front Control loop closed. The STOP analysis was also used to verify that the optical/structural/thermal design provides the extreme stability required for planet characterization in the presence of thermal disturbances expected in a typical observing scenario. This paper describes the instrument design and the flow down from science requirements to high level engineering requirements.

  13. Selected, annotated bibliography of studies relevant to the isolation of nuclear wastes. [705 references

    SciTech Connect

    Hyder, L.K.; Fore, C.S.; Vaughan, N.D.; Faust, R.A.

    1980-09-01

    This annotated bibliography of 705 references represents the first in a series to be published by the Ecological Sciences Information Center containing scientific, technical, economic, and regulatory information relevant to nuclear waste isolation. Most references discuss deep geologic disposal, with fewer studies of deep seabed disposal; space disposal is also included. The publication covers both domestic and foreign literature for the period 1954 to 1980. Major chapters selected are Chemical and Physical Aspects; Container Design and Performance; Disposal Site; Envirnmental Transport; General Studies and Reviews; Geology, Hydrology and Site Resources; Regulatory and Economic Aspects; Repository Design and Engineering; Transportation Technology; Waste Production; and Waste Treatment. Specialized data fields have been incorporated to improve the ease and accuracy of locating pertinent references. Specific radionuclides for which data are presented are listed in the Measured Radionuclides field, and specific parameters which affect the migration of these radionuclides are presented in the Measured Parameters field. The references within each chapter are arranged alphabetically by leading author, corporate affiliation, or title of the document. When the author is not given, the corporate affiliation appears first. If these two levels of authorship are not given, the title of the document is used as the identifying level. Indexes are provided for author(s), keywords, subject category, title, geographic location, measured parameters, measured radionuclides, and publication description.

  14. INTRODUCTION AND STUDY DESIGN

    EPA Science Inventory

    Under the sponsorship of the UNEP/ILO/IPCS, 17 laboratories from diverse regions of the world participated in evaluating the utility of four plant bioassays for detecting genetic hazards of environmental chemicals. he bioassays included in this collaborative study were Arabidopsi...

  15. Women's Studies: A Student's Guide to Reference Sources.

    ERIC Educational Resources Information Center

    Wright, Maureen, Comp.

    This annotated bibliography lists 73 reference items on the subject of women which are in the Reference Department of McLennan Library at McGill University. Entries are listed according to several categories: directories; encyclopedias; biographical sources; and bibliographies--bibliography, current, general, and specific (Canadian women,…

  16. CHARACTERIZATION OF REFERENCE ARTEMIA III FOR MARINE TOXICOLOGICAL STUDIES

    EPA Science Inventory

    ASTM Practice for Using Brine Shrimp Nauplii as Food for Test Animals in Aquatic Toxicology Tests (E 1203) suggests use of Reference Artemis as a reference standard for evaluating other batches of brine shrimp as food for organisms used in toxicology. in 1988, the U.S. EPA was ab...

  17. Design verification of large time constant thermal shields for optical reference cavities.

    PubMed

    Zhang, J; Wu, W; Shi, X H; Zeng, X Y; Deng, K; Lu, Z H

    2016-02-01

    In order to achieve high frequency stability in ultra-stable lasers, the Fabry-Pérot reference cavities shall be put inside vacuum chambers with large thermal time constants to reduce the sensitivity to external temperature fluctuations. Currently, the determination of thermal time constants of vacuum chambers is based either on theoretical calculation or time-consuming experiments. The first method can only apply to simple system, while the second method will take a lot of time to try out different designs. To overcome these limitations, we present thermal time constant simulation using finite element analysis (FEA) based on complete vacuum chamber models and verify the results with measured time constants. We measure the thermal time constants using ultrastable laser systems and a frequency comb. The thermal expansion coefficients of optical reference cavities are precisely measured to reduce the measurement error of time constants. The simulation results and the experimental results agree very well. With this knowledge, we simulate several simplified design models using FEA to obtain larger vacuum thermal time constants at room temperature, taking into account vacuum pressure, shielding layers, and support structure. We adopt the Taguchi method for shielding layer optimization and demonstrate that layer material and layer number dominate the contributions to the thermal time constant, compared with layer thickness and layer spacing. PMID:26931831

  18. A reference frame formulation for the analysis and design of steady manufacturing processes

    NASA Astrophysics Data System (ADS)

    Balagangadhar, Dinesh

    A reference frame formulation for large deformation steady state processes is proposed. The displacement and material state variables appear as the primary response fields in this mixed formulation. Unlike displacement based Lagrangian formulations, our formulation does not require a transient analysis to simulate a quasi-steady process and yields results that are free of numerical oscillations and which require considerably less computational effort. And unlike velocity based Eulerian methods, our formulation does not require free surface corrections or streamline integration algorithms. An iterative design environment for quasi-steady forming processes is developed from the computationally efficient reference frame formulation. The direct differentiation method is used to efficiently evaluate the response sensitivities. Select forming response measures and their sensitivities are combined with nonlinear programming methods to optimize the process. Three example problems are presented to demonstrate the efficiency of the proposed formulations: a laser surface treatment process is analyzed, a drawing process is analyzed and optimized and a multi-pass rolling process is analyzed and designed.

  19. A Local Reference For Bar Studies In The Distant Universe

    NASA Astrophysics Data System (ADS)

    Menéndez-Delmestre, Karín; Sheth, Kartik; S4G Team

    2015-08-01

    Stellar bars are present in ~2/3 of nearby spirals and play a critical role in the evolution of their hosts. With the advent of large high-resolution imaging surveys, bar studies are being extended to distant galaxies. However, photometric studies of the distant universe are invariably subject to the effects of band-shifting, the progressive shift of the photometric band to bluer rest-frame wavelengths. In order to reliably characterize the intrinsic evolution of bars with redshift, safe from band-shifting effects, it is necessary to establish a local anchor of how bar properties vary with wavelength. We present a detailed multi-band study of bar properties from UV through mid-infrared for a sample of 16 large nearby barred galaxies. Based on ellipticity and position angle profiles resulting from fitting elliptical isophotes to the 2D light distribution of each galaxy, we find that both the bar length and the bar ellipticity increase at bluer wavebands. We attribute the increase in bar length to the frequent presence of prominent star forming knots at the end of bars: these regions are significantly brighter in bluer bands, resulting in the “artificial” lengthening of the bar. The increase in bar ellipticity, on the other hand, is driven by the bulge size: the bulge, composed primarily of old/red stars, is less prominent at bluer bands, allowing for thinner ellipses to be fit within the bar region. The resulting effect is that bars appear longer and thinner at bluer bands. Although we find that ~50% of the bars disappear in the UV, the results on bar ellipticity and length extend to those cases in which the bar is still visible in the UV. These results imply that careful correction for band-shifting effects is necessary for high-z studies to reliably gauge any intrinsic evolution of the bar properties with redshift. In the light of the ample space-based optical data now available, this study may be used as a reference to implement band-shifting corrections to

  20. A study on reference standard for cytotoxicity assay of biomaterials.

    PubMed

    Oshima, H; Nakamura, M

    1994-01-01

    The objective of the present study was to find a standard substance for use as a reference in the cytotoxicity assay of biomaterials, as an alternative to animal experiments in recent years. Eight kinds of rubber were made in a plate shape to keep their surface area at 1 cm2 against 10 ml of extract volume. They were extracted by the following three extraction methods (a) dynamic extraction at 200 rpm gyration on alumina balls at 37 degrees C for 24 h; (b) static extraction at 37 degrees C for 24 h and (c) extraction by heating in an autoclave at 121 degrees C for 60 min. At the end of each period each extract was examined for cell viability based on an evaluation by neutral red uptake. These methods were repeated up to seven times. Two kinds of chemicals were also tested. The extracts obtained were used to treat human gingival fibroblasts that have been cultured with DMEM supplemented with 5% fetal bovine serum into a 96 well tissue culture plate by 1 x 10(5) cells/ml, in an incubator aerated with 5% CO2, and 95% humidified air at 37 degrees C for 48 h. The extracts of ethylene-propylene, butyl, nitrile rubbers, and two kinds of chemicals yielded strong cytotoxicity in all three kinds of extraction methods, while chloroprene, fluorine-contained, isoprene, India, and silicone rubbers showed little cytotoxicity. The results obtained by the three kinds of extraction methods revealed no differences in the order of cytotoxicity of the materials tested.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7950880

  1. RAD hard PROM design study

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The results of a preliminary study on the design of a radiation hardened fusible link programmable read-only memory (PROM) are presented. Various fuse technologies and the effects of radiation on MOS integrated circuits are surveyed. A set of design rules allowing the fabrication of a radiation hardened PROM using a Si-gate CMOS process is defined. A preliminary cell layout was completed and the programming concept defined. A block diagram is used to describe the circuit components required for a 4 K design. A design goal data sheet giving target values for the AC, DC, and radiation parameters of the circuit is presented.

  2. Candidate reference genes for gene expression studies in water lily.

    PubMed

    Luo, Huolin; Chen, Sumei; Wan, Hongjian; Chen, Fadi; Gu, Chunsun; Liu, Zhaolei

    2010-09-01

    The selection of an appropriate reference gene(s) is a prerequisite for the proper interpretation of quantitative Real-Time polymerase chain reaction data. We report the evaluation of eight candidate reference genes across various tissues and treatments in the water lily by the two software packages geNorm and NormFinder. Across all samples, clathrin adaptor complexes medium subunit (AP47) and actin 11 (ACT11) emerged as the most suitable reference genes. Across different tissues, ACT11 and elongation factor 1-alpha (EF1alpha) exhibited a stable expression pattern. ACT11 and AP47 also stably expressed in roots subjected to various treatments, but in the leaves of the same plants the most stably expressed genes were ubiquitin-conjugating enzyme 16 (UBC16) and ACT11. PMID:20452325

  3. Designing case-control studies.

    PubMed Central

    Yanagawa, T

    1979-01-01

    Identification of confounding factors, evaluation of their influence on cause-effect associations, and the introduction of appropriate ways to account for these factors are important considerations in designing case-control studies. This paper presents designs useful for these purposes, after first providing a statistical definition of a confounding factor. Differences in the ability to identify and evaluate confounding factors and estimate disease risk between designs employing stratification (matching) and designs randomly sampling cases and controls are noted. Linear logistic models for the analysis of data from such designs are described and are shown to liberalize design requirements and to increase relative risk estimation efficiency. The methods are applied to data from a multiple factor investigation of lung cancer patients and controls. PMID:540588

  4. Technical Reference Suite Addressing Challenges of Providing Assurance for Fault Management Architectural Design

    NASA Technical Reports Server (NTRS)

    Fitz, Rhonda; Whitman, Gerek

    2016-01-01

    Research into complexities of software systems Fault Management (FM) and how architectural design decisions affect safety, preservation of assets, and maintenance of desired system functionality has coalesced into a technical reference (TR) suite that advances the provision of safety and mission assurance. The NASA Independent Verification and Validation (IVV) Program, with Software Assurance Research Program support, extracted FM architectures across the IVV portfolio to evaluate robustness, assess visibility for validation and test, and define software assurance methods applied to the architectures and designs. This investigation spanned IVV projects with seven different primary developers, a wide range of sizes and complexities, and encompassed Deep Space Robotic, Human Spaceflight, and Earth Orbiter mission FM architectures. The initiative continues with an expansion of the TR suite to include Launch Vehicles, adding the benefit of investigating differences intrinsic to model-based FM architectures and insight into complexities of FM within an Agile software development environment, in order to improve awareness of how nontraditional processes affect FM architectural design and system health management.

  5. Characterization of bandgap reference circuits designed for high energy physics applications

    NASA Astrophysics Data System (ADS)

    Traversi, G.; De Canio, F.; Gaioni, L.; Manghisoni, M.; Mattiazzo, S.; Ratti, L.; Re, V.; Riceputi, E.

    2016-07-01

    The objective of this work is to design a high performance bandgap voltage reference circuit in a standard commercial 65 nm CMOS technology capable of operating in harsh radiation environments. A prototype circuit based on three different devices (diode, bipolar transistor and MOSFET) was fabricated and tested. Measurement results show a temperature variation as low as ±3.4 mV over a temperature range of 170 ° C (-30 °C to 140 °C) and a line regulation at room temperature of 5.2%/V. Measured VREF is 690 mV±15 mV (3σ) for 26 samples on the same wafer. Circuits correctly operate with supply voltages in the range from 1.32 V down to 0.78 V. A reference voltage shift of only 7.6 mV (around 1.1%) was measured after irradiation with 10 keV X-rays up to an integrated dose of 225 Mrad (SiO2).

  6. Performance of three 4. 5 m dipoles for SSC reference design D

    SciTech Connect

    Dahl, P.; Cottingham, J.; Fernow, R.; Garber, M.; Ghosh, A.; Goodzeit, C.; Greene, A.; Herrera, J.; Kahn, S.; Kelly, E.

    1985-01-01

    Three 4.5 m long dipoles for Reference Design D of the proposed Superconducting Super Collider have been successfully tested. The magnets are cold-iron (and cold bore) 1-in-1 dipoles, wound with current density-graded high homogeneity NbTi cable in a two-layer cos theta coil of 40 mm inner diameter. The coil is prestressed by 15 mm wide stainless steel collars, and mounted in a circular, split iron yoke of 267 mm outer diameter, supported in a cylindrical yoke containment vessel. At 4.5 K the magnets reached a field of about 6.6T with little training, or the short sample limit of the conductor, and in subcooled (2.6 to 2.4 K) liquid, 8T was achieved. The allowed harmonics were close to the predicted values, and the unallowed harmonics small. The sextupole trim coil operated at eight times the required current without training.

  7. Rocky Flats Plant fluidized-bed incinerator. Engineering design and reference manual

    SciTech Connect

    Meile, L.J.

    1982-11-05

    The information in this manual is being presented to complete the documentation of the fluidized-bed incineration (FBI) process development at the Rocky Flats Plant. The information pertains to the 82-kg/hour demonstration unit at the Rocky Flats Plant. This document continues the presentation of design reference material in the aeas of equipment drawings, space requirements, and unit costs. In addition, appendices contain an operating procedure and an operational safety analysis of the process. The cost figures presented are based on 1978 dollars and have not been converted to a current dollar value. Also, the cost of modifications are not included, since they would be insignificant if they were incorporated into a new installation.

  8. [Study of image quality at various positions of reference scan].

    PubMed

    Takatsu, Yasuo; Umezaki, Yoshie; Miyati, Tosiaki

    2013-03-01

    In magnetic resonance imaging (MRI), we can use sensitivity encoding (SENSE) as a parallel imaging reconstruct from aliasing based on the sensitivity map of each coil element by reference scan. We researched SENSE reconstruction depending on the position of the reference scan. 1.5 T MRI (Achiva, Philips), 32-channel SENSE cardiac coil and rectangular solid phantom (nickel chloride) were used. Seven slices (A to G: from head to foot) were set at the phantom, slice thickness was 1 cm, and each slice interval was 5 cm. When T2 weighted axial images (TR: 3000 ms, TE: 120 ms) were taken, the center of the reference scan (C-Ref) was changed A to G, SENSE factor was changed 1 to 5, and number of signals averaged (NSA) was changed 1 to 3 with fold over suppression. Signal-to-noise ratio (SNR) and coefficient of variation (CV) from 9 regions of interest (ROI) of axial images were calculated. The SNR of slices A and G were lower than the other slices. %CV of slices F with C-Ref D was 69.4% lower than C-Ref A. %CV of slices D to F were higher than the other slices when C-Ref was A. %CV had no relation with SNR. Therefore, a 30 cm area around the center of reference can obtain best SENSE reconstruction. PMID:23514855

  9. Instant Messaging Reference in an Academic Library: A Case Study.

    ERIC Educational Resources Information Center

    Foley, Marianne

    2002-01-01

    During the 2000-2001 academic year, the General Libraries of the University at Buffalo conducted a pilot project to assess feasibility of providing reference through instant messaging. Describes the project, its implementation, the software used, staffing issues, and publicity efforts. Discusses results of the project in terms of user…

  10. Technical Reference Suite Addressing Challenges of Providing Assurance for Fault Management Architectural Design

    NASA Technical Reports Server (NTRS)

    Fitz, Rhonda; Whitman, Gerek

    2016-01-01

    Research into complexities of software systems Fault Management (FM) and how architectural design decisions affect safety, preservation of assets, and maintenance of desired system functionality has coalesced into a technical reference (TR) suite that advances the provision of safety and mission assurance. The NASA Independent Verification and Validation (IV&V) Program, with Software Assurance Research Program support, extracted FM architectures across the IV&V portfolio to evaluate robustness, assess visibility for validation and test, and define software assurance methods applied to the architectures and designs. This investigation spanned IV&V projects with seven different primary developers, a wide range of sizes and complexities, and encompassed Deep Space Robotic, Human Spaceflight, and Earth Orbiter mission FM architectures. The initiative continues with an expansion of the TR suite to include Launch Vehicles, adding the benefit of investigating differences intrinsic to model-based FM architectures and insight into complexities of FM within an Agile software development environment, in order to improve awareness of how nontraditional processes affect FM architectural design and system health management. The identification of particular FM architectures, visibility, and associated IV&V techniques provides a TR suite that enables greater assurance that critical software systems will adequately protect against faults and respond to adverse conditions. Additionally, the role FM has with regard to strengthened security requirements, with potential to advance overall asset protection of flight software systems, is being addressed with the development of an adverse conditions database encompassing flight software vulnerabilities. Capitalizing on the established framework, this TR suite provides assurance capability for a variety of FM architectures and varied development approaches. Research results are being disseminated across NASA, other agencies, and the

  11. Perspectives toward the stereotype production method for public symbol design: a case study of novice designers.

    PubMed

    Ng, Annie W Y; Siu, Kin Wai Michael; Chan, Chetwyn C H

    2013-01-01

    This study investigated the practices and attitudes of novice designers toward user involvement in public symbol design at the conceptual design stage, i.e. the stereotype production method. Differences between male and female novice designers were examined. Forty-eight novice designers (24 male, 24 female) were asked to design public symbol referents based on suggestions made by a group of users in a previous study and provide feedback with regard to the design process. The novice designers were receptive to the adoption of user suggestions in the conception of the design, but tended to modify the pictorial representations generated by the users to varying extents. It is also significant that the male and female novice designers appeared to emphasize different aspects of user suggestions, and the female novice designers were more positive toward these suggestions than their male counterparts. The findings should aid the optimization of the stereotype production method for user-involved symbol design. PMID:22632980

  12. Multi-omics data driven analysis establishes reference codon biases for synthetic gene design in microbial and mammalian cells.

    PubMed

    Ang, Kok Siong; Kyriakopoulos, Sarantos; Li, Wei; Lee, Dong-Yup

    2016-06-01

    In this study, we analyzed multi-omics data and subsets thereof to establish reference codon usage biases for codon optimization in synthetic gene design. Specifically, publicly available genomic, transcriptomic, proteomic and translatomic data for microbial and mammalian expression hosts, Escherichia coli, Saccharomyces cerevisiae, Pichia pastoris and Chinese hamster ovary (CHO) cells, were compiled to derive their individual codon and codon pair frequencies. Then, host dependent and -omics specific codon biases were generated and compared by principal component analysis and hierarchical clustering. Interestingly, our results indicated the similar codon bias patterns of the highly expressed transcripts, highly abundant proteins, and efficiently translated mRNA in microbial cells, despite the general lack of correlation between mRNA and protein expression levels. However, for CHO cells, the codon bias patterns among various -omics subsets are not distinguishable, forming one cluster. Thus, we further investigated the effect of different input codon biases on codon optimized sequences using the codon context (CC) and individual codon usage (ICU) design parameters, via in silico case study on the expression of human IFNγ sequence in CHO cells. The results supported that CC is more robust design parameter than ICU for improved heterologous gene design. PMID:26850284

  13. Optical Telescope Design Study Results

    NASA Astrophysics Data System (ADS)

    Livas, J.; Sankar, S.

    2015-05-01

    We report on the results of a study conducted from Nov 2012-Apr 2013 to develop a telescope design for a space-based gravitational wave detector. The telescope is needed for efficient power delivery but since it is directly in the beam path, the design is driven by the requirements for the overall displacement sensitivity of the gravitational wave observatory. Two requirements in particular, optical pathlength stability and scattered light performance, are beyond the usual specifications for good image quality encountered in traditional telescopic systems. An important element of the study was to tap industrial expertise to develop an optimized design that can be reliably manufactured. Key engineering and design trade-offs and the sometimes surprising results will be presented.

  14. Multinomial tree models for assessing the status of the reference in studies of the accuracy of tools for binary classification

    PubMed Central

    Botella, Juan; Huang, Huiling; Suero, Manuel

    2013-01-01

    Studies that evaluate the accuracy of binary classification tools are needed. Such studies provide 2 × 2 cross-classifications of test outcomes and the categories according to an unquestionable reference (or gold standard). However, sometimes a suboptimal reliability reference is employed. Several methods have been proposed to deal with studies where the observations are cross-classified with an imperfect reference. These methods require that the status of the reference, as a gold standard or as an imperfect reference, is known. In this paper a procedure for determining whether it is appropriate to maintain the assumption that the reference is a gold standard or an imperfect reference, is proposed. This procedure fits two nested multinomial tree models, and assesses and compares their absolute and incremental fit. Its implementation requires the availability of the results of several independent studies. These should be carried out using similar designs to provide frequencies of cross-classification between a test and the reference under investigation. The procedure is applied in two examples with real data. PMID:24106484

  15. Equilibrium Studies of Designed Metalloproteins.

    PubMed

    Gibney, B R

    2016-01-01

    Complete thermodynamic descriptions of the interactions of cofactors with proteins via equilibrium studies are challenging, but are essential to the evaluation of designed metalloproteins. While decades of studies on protein-protein interaction thermodynamics provide a strong underpinning to the successful computational design of novel protein folds and de novo proteins with enzymatic activity, the corresponding paucity of data on metal-protein interaction thermodynamics limits the success of computational metalloprotein design efforts. By evaluating the thermodynamics of metal-protein interactions via equilibrium binding studies, protein unfolding free energy determinations, proton competition equilibria, and electrochemistry, a more robust basis for the computational design of metalloproteins may be provided. Our laboratory has shown that such studies provide detailed insight into the assembly and stability of designed metalloproteins, allow for parsing apart the free energy contributions of metal-ligand interactions from those of porphyrin-protein interactions in hemeproteins, and even reveal their mechanisms of proton-coupled electron transfer. Here, we highlight studies that reveal the complex interplay between the various equilibria that underlie metalloprotein assembly and stability and the utility of making these detailed measurements. PMID:27586343

  16. Homogeneity study of candidate reference material in fish matrix

    NASA Astrophysics Data System (ADS)

    Ulrich, J. C.; Sarkis, J. E. S.; Hortellani, M. A.

    2015-01-01

    A material is perfectly homogeneous with respect to a given characteristic, or composition, if there is no difference between the values obtained from one part to another. Homogeneity is usually evaluated using analysis of variance (ANOVA). However, the requirement that populations of data to be processed must have a normal distribution and equal variances greatly limits the use of this statistical tool. A more suitable test for assessing the homogeneity of RMs, known as "sufficient homogeneity", was proposed by Fearn and Thompson. In this work, we evaluate the performance of the two statistical treatments for assessing homogeneity of methylmercury (MeHg) in candidate reference material of fish tissue.

  17. Stability study of realization of the celestial reference frame

    NASA Astrophysics Data System (ADS)

    Yatskiv, Ya. S.; Bolotin, S. L.; Kur'yanova, A. N.

    2004-09-01

    We present a short overview of the activity of the IERS as well as the Main Astronomical Observatory (MAO) of the National Academy of Sciences of Ukraine for maintenance and extention of the International Celestial Reference Frame (ICRF). Special attention is given to the time stabilities of positions of radio sources (RS) and to the selection of a subset of RS to be used for maintenance of the ICRF. It is shown that seven RS qualified by the IERS as defining sources are unstable.

  18. Visual Design Principles: An Empirical Study of Design Lore

    ERIC Educational Resources Information Center

    Kimball, Miles A.

    2013-01-01

    Many books, designers, and design educators talk about visual design principles such as balance, contrast, and alignment, but with little consistency. This study uses empirical methods to explore the lore surrounding design principles. The study took the form of two stages: a quantitative literature review to determine what design principles are…

  19. REFERENCE MANUAL FOR RASSMIT VERSION 2.1: SUB-SLAB DEPRESSURIZATION SYSTEM DESIGN PERFORMANCE SIMULATION PROGRAM

    EPA Science Inventory

    The report is a reference manual for RASSMlT Version 2.1, a computer program that was developed to simulate and aid in the design of sub-slab depressurization systems used for indoor radon mitigation. The program was designed to run on DOS-compatible personal computers to ensure ...

  20. The X-ray Microcalorimeter Spectrometer (XMS): A Reference Cryogenic Instrument Design for Constellation-X

    NASA Technical Reports Server (NTRS)

    Whitehouse, Paul L.

    2003-01-01

    Constellation-X, a mission now belonging to the Beyond Einstein initiative, is being planned to inherit the x-ray sky from Chandra, XMM-Newton and Astro-E. The first two of four observatories in the constellation will be launched together in 2013 and followed a year later by the launch of the remaining two. The four will independently orbit the Sun-Earth Lagrange point L2. An instrument compliment resides in the Focal Plane Module (FPM) of each observatory 10 m from the Optics Module and consists of three Hard X-ray Telescope (HXT) detectors, a Reflection Grating Spectrometer (RGS) focal plane CCD camera and an X-ray Microcalorimeter Spectrometer (XMS). Instrument awards are scheduled for early 2006. The reference detector for XMS is a 32 x 32 array of microcalorimetric superconducting Transition Edge Sensors (TES). Each pixel casts a variable resistance in a SQUID based multiplexed readout circuit which is coupled to series SQUID arrays for amplification and finally read out by external electronics. A multi-stage continuous ADR will provide the stable 50 mK desired for the TES array and a stable 1 K for the series SQUID arrays while also lifting thermal parasitic and inefficiency loads to a 6 K cryocooler interface. The 6 K cryocooler is expected to emerge from the joint-project Advanced Cryocooler Technology Development Program (ACTDP) in which Constellation-X is an active participant. Project Pre-Formulation activities are marked by extensive technology development necessitating early, but realistic, thermal and cooling load requirements for ADR and ACTDP-cryocooler design points. Such requirements are driven by the encompassing XMS cryostat and ultimately by the thermal environment imposed by the FPM. It is further desired that the XMS instrument be able to operate on its side in the laboratory, with a warm vacuum shell, during an extensive calibration regime. It is that reference system design of the XMS instrument (microcalorimeter, ADR, cryocooler and

  1. [Study on crocins reference extract and application on assay of Croci Stigma].

    PubMed

    He, Feng-yan; Dai, Zhong; He, Yi; Zhang, Yu-mei; Lu, Jing

    2015-06-01

    High price and poor stability of both crocin-1 and crocin-2 reference substance have become obstacles to HPLC assay of Croci Stigma. A new method based on reference extract was proposed. In this study, the reference extract was prepared from gardenia yellow which is cheap and easy to get The content of crocin-1 and crocin-2 in reference extract was determined and factors affecting stability of reference extract were investigated. Twelve batches of Croci Stigma were analyzed with reference extract and reference substance respectively. The results showed no difference. The presented method is feasible for quality control of Croci Stigma and reference extract is suitable to replace reference substances in assay. PMID:26591529

  2. Vehicle occupancy detection camera position optimization using design of experiments and standard image references

    NASA Astrophysics Data System (ADS)

    Paul, Peter; Hoover, Martin; Rabbani, Mojgan

    2013-03-01

    Camera positioning and orientation is important to applications in domains such as transportation since the objects to be imaged vary greatly in shape and size. In a typical transportation application that requires capturing still images, inductive loops buried in the ground or laser trigger sensors are used when a vehicle reaches the image capture zone to trigger the image capture system. The camera in such a system is in a fixed position pointed at the roadway and at a fixed orientation. Thus the problem is to determine the optimal location and orientation of the camera when capturing images from a wide variety of vehicles. Methods from Design for Six Sigma, including identifying important parameters and noise sources and performing systematically designed experiments (DOE) can be used to determine an effective set of parameter settings for the camera position and orientation under these conditions. In the transportation application of high occupancy vehicle lane enforcement, the number of passengers in the vehicle is to be counted. Past work has described front seat vehicle occupant counting using a camera mounted on an overhead gantry looking through the front windshield in order to capture images of vehicle occupants. However, viewing rear seat passengers is more problematic due to obstructions including the vehicle body frame structures and seats. One approach is to view the rear seats through the side window. In this situation the problem of optimally positioning and orienting the camera to adequately capture the rear seats through the side window can be addressed through a designed experiment. In any automated traffic enforcement system it is necessary for humans to be able to review any automatically captured digital imagery in order to verify detected infractions. Thus for defining an output to be optimized for the designed experiment, a human defined standard image reference (SIR) was used to quantify the quality of the line-of-sight to the rear seats of

  3. Los Alamos Controlled Air Incinerator for radioactive waste. Volume II. Engineering design reference manual

    SciTech Connect

    Koenig, R.A.; Draper, W.E.; Newmyer, J.M.; Warner, C.L.

    1982-10-01

    This two-volume report is a detailed design and operating documentation of the Los Alamos National Laboratory Controlled Air Incinerator (CAI) and is an aid to technology transfer to other Department of Energy contractor sites and the commercial sector. Volume I describes the CAI process, equipment, and performance, and it recommends modifications based on Los Alamos experience. It provides the necessary information for conceptual design and feasibility studies. Volume II provides descriptive engineering information such as drawings, specifications, calculations, and costs. It aids duplication of the process at other facilities.

  4. Diffusive Barrier and Getter Under Waste Packages VA Reference Design Feature Evaluations

    SciTech Connect

    MacNeil, K.

    1999-05-24

    This technical document evaluates those aspects of the diffusive barrier and getter features which have the potential for enhancing the performance of the Viability Assessment Reference Design and are also directly related to the key attributes for the repository safety strategy of that design. The effects of advection, hydrodynamic dispersion, and diffusion on the radionuclide migration rates through the diffusive barrier were determined through the application of the one-dimensional, advection/dispersion/diffusion equation. The results showed that because advective flow described by the advection-dispersion equation dominates, the diffusive barrier feature alone would not be effective in retarding migration of radiocuclides. However, if the diffusive barrier were combined with one or more features that reduced the potential for advection, then transport of radionuclides would be dominated by diffusion and their migration from the EBS would be impeded. Apatite was chosen as the getter material used for this report. Two getter configurations were developed, Case 1 and Case 2. As in the evaluation of the diffusive barrier, the effects of advection, hydrodynamic dispersion, and diffusion on the migration of radionuclides through the getter are evaluated. However, in addition to these mechanisms, the one-dimensional advection/dispersion/diffusion model is modified to include the effect of sorption on radionuclide migration rates through the sorptive medium (getter). As a result of sorption, the longitudinal dispersion coefficient, and the average linear velocity are effectively reduced by the retardation factor. The retardation factor is a function of the getter material's dry bulk density, sorption coefficient and moisture content. The results of the evaluation showed that a significant delay in breakthrough through the getter can be achieved if the thickness of the getter barrier is increased.

  5. Design of a Model Reference Adaptive Controller for an Unmanned Air Vehicle

    NASA Technical Reports Server (NTRS)

    Crespo, Luis G.; Matsutani, Megumi; Annaswamy, Anuradha M.

    2010-01-01

    This paper presents the "Adaptive Control Technology for Safe Flight (ACTS)" architecture, which consists of a non-adaptive controller that provides satisfactory performance under nominal flying conditions, and an adaptive controller that provides robustness under off nominal ones. The design and implementation procedures of both controllers are presented. The aim of these procedures, which encompass both theoretical and practical considerations, is to develop a controller suitable for flight. The ACTS architecture is applied to the Generic Transport Model developed by NASA-Langley Research Center. The GTM is a dynamically scaled test model of a transport aircraft for which a flight-test article and a high-fidelity simulation are available. The nominal controller at the core of the ACTS architecture has a multivariable LQR-PI structure while the adaptive one has a direct, model reference structure. The main control surfaces as well as the throttles are used as control inputs. The inclusion of the latter alleviates the pilot s workload by eliminating the need for cancelling the pitch coupling generated by changes in thrust. Furthermore, the independent usage of the throttles by the adaptive controller enables their use for attitude control. Advantages and potential drawbacks of adaptation are demonstrated by performing high fidelity simulations of a flight-validated controller and of its adaptive augmentation.

  6. A Design Method of Code Correlation Reference Waveform in GNSS Based on Least-Squares Fitting.

    PubMed

    Xu, Chengtao; Liu, Zhe; Tang, Xiaomei; Wang, Feixue

    2016-01-01

    The multipath effect is one of the main error sources in the Global Satellite Navigation Systems (GNSSs). The code correlation reference waveform (CCRW) technique is an effective multipath mitigation algorithm for the binary phase shift keying (BPSK) signal. However, it encounters the false lock problem in code tracking, when applied to the binary offset carrier (BOC) signals. A least-squares approximation method of the CCRW design scheme is proposed, utilizing the truncated singular value decomposition method. This algorithm was performed for the BPSK signal, BOC(1,1) signal, BOC(2,1) signal, BOC(6,1) and BOC(7,1) signal. The approximation results of CCRWs were presented. Furthermore, the performances of the approximation results are analyzed in terms of the multipath error envelope and the tracking jitter. The results show that the proposed method can realize coherent and non-coherent CCRW discriminators without false lock points. Generally, there is performance degradation in the tracking jitter, if compared to the CCRW discriminator. However, the performance promotions in the multipath error envelope for the BOC(1,1) and BPSK signals makes the discriminator attractive, and it can be applied to high-order BOC signals. PMID:27483275

  7. A Cross-Cultural Study of Reference Point Adaptation: Evidence from China, Korea, and the US

    ERIC Educational Resources Information Center

    Arkes, Hal R.; Hirshleifer, David; Jiang, Danling; Lim, Sonya S.

    2010-01-01

    We examined reference point adaptation following gains or losses in security trading using participants from China, Korea, and the US. In both questionnaire studies and trading experiments with real money incentives, reference point adaptation was larger for Asians than for Americans. Subjects in all countries adapted their reference points more…

  8. Design and characterisation of a thin-film electrode array with shared reference/counter electrodes for electrochemical detection.

    PubMed

    Uludag, Yildiz; Olcer, Zehra; Sagiroglu, Mahmut Samil

    2014-07-15

    In the current study, a novel electrode array and integrated microfluidics have been designed and characterised in order to create a sensor chip which is not only easy, rapid and cheaper to produce but also have a smaller imprint and good electrochemical sensing properties. The current study includes the assessment of the effects of an Au quasi-reference electrode and the use of shared reference/counter electrodes for the array, in order to obtain a small array that can be produced using a fine metal mask. In the study, it is found that when Au is used as the quasi-reference electrode, the arrays with shared reference and counter electrodes result in faster electron transfer kinetics and prevent the potential change with respect to scan rate, and hence is advantageous with respect to conventional electrodes. In addition, the resulting novel electrode array has been shown to result in higher current density (10.52 µA/cm(2); HRP detection assay) and measured diffusion coefficient (14.40×10(-12) cm(2)/s; calculated from the data of cyclic voltammetry with 1mM potassium ferricyanide) with respect to conventional electrodes tested in the study. Using the new electrode arrays, the detection limits obtained from horse radish peroxidase (HRP) and bisphenol A assays were 12.5 ng/ml (2.84×10(-10) M ) and 10 ng/ml (44×10(-9) M), respectively. Performing the HRP detection assay in a flow injection system using array integrated microfluidics provided 25 times lower detection limit (11.36×10(-12) M), although Ti has been used as electrode material instead of Au. In short, incorporation of this new electrode array to lab-on-a-chip or MEMs (micro-electro mechanic systems) technologies may pave the way for easy to use automated biosensing devices that could be used for a variety of applications from diagnostics to environmental monitoring, and studies will continue to move forward in this direction. PMID:24561521

  9. Bioequivalence study of levothyroxine tablets compared to reference tablets and an oral solution.

    PubMed

    Koytchev, Rossen; Lauschner, Reinhard

    2004-01-01

    The study was designed to evaluate the bioequivalence of three levothyroxine sodium (CAS 51-48-9) formulations, i.e. a test and a reference tablet and an oral solution. A bioequivalence study was carried out in 25 healthy volunteers, who were administered a single dose of 600 microg levothyroxine in the form of the test formulation (levothyroxine sodium tablets 200 microg; Eferox), the originator product, and an oral solution. The trial was performed in one study center according to an open, randomized, three-way cross-over design with wash-out periods of 35 days between administration. Blood samples were taken up to 48 h post dose, the plasma was separated and the concentrations of levothyroxine and triiodothyronine were determined by radioimmunoassay with I125 labeling method. The levothyroxine mean Cmax were 112.0+/-17.3 ng/ml, 113.4+/-18.5 ng/ ml and 111.3+/-15.1 ng/ml, while the mean AUC0-24 were 2263.7+/-332.8 ng x h/ ml, 2307.3+/-351.3 ng x h/ml and 2286.1+/-331.0 ng x h/ml for the test and reference tablets as well as for the oral solution, respectively. No significant differences were found of principal pharmacokinetic parameters between the studied formulations. The 90%-confidence interval for the primary target parameters, intra-individual ratios of AUC0-24 and Cmax of levothyroxine were within the acceptance ranges for bioequivalence trials, i.e. AUC0-24 0.954-1.016 and 0.966-1.011 as well as Cmax 0.948-1.027 and 0.968-1.032 for test tablets versus reference tablets and the oral solution, respectively. Similar results were observed for triiodothyronine. In the light of the present study it can be concluded that the levothyroxine test tablet is bioequivalent to the reference formulation in respect of extent and rate of absorption. The results of the present trial confirm the findings of a previous study, performed under steady-state conditions with Eferox tablets 100 microg in patients without thyroid function. PMID:15553108

  10. Adjoint-Based Design of Rotors Using the Navier-Stokes Equations in a Noninertial Reference Frame

    NASA Technical Reports Server (NTRS)

    Nielsen, Eric J.; Lee-Rausch, Elizabeth M.; Jones, William T.

    2010-01-01

    Optimization of rotorcraft flowfields using an adjoint method generally requires a time-dependent implementation of the equations. The current study examines an intermediate approach in which a subset of rotor flowfields are cast as steady problems in a noninertial reference frame. This technique permits the use of an existing steady-state adjoint formulation with minor modifications to perform sensitivity analyses. The formulation is valid for isolated rigid rotors in hover or where the freestream velocity is aligned with the axis of rotation. Discrete consistency of the implementation is demonstrated by using comparisons with a complex-variable technique, and a number of single- and multipoint optimizations for the rotorcraft figure of merit function are shown for varying blade collective angles. Design trends are shown to remain consistent as the grid is refined.

  11. Adjoint-Based Design of Rotors using the Navier-Stokes Equations in a Noninertial Reference Frame

    NASA Technical Reports Server (NTRS)

    Nielsen, Eric J.; Lee-Rausch, Elizabeth M.; Jones, William T.

    2009-01-01

    Optimization of rotorcraft flowfields using an adjoint method generally requires a time-dependent implementation of the equations. The current study examines an intermediate approach in which a subset of rotor flowfields are cast as steady problems in a noninertial reference frame. This technique permits the use of an existing steady-state adjoint formulation with minor modifications to perform sensitivity analyses. The formulation is valid for isolated rigid rotors in hover or where the freestream velocity is aligned with the axis of rotation. Discrete consistency of the implementation is demonstrated using comparisons with a complex-variable technique, and a number of single- and multi-point optimizations for the rotorcraft figure of merit function are shown for varying blade collective angles. Design trends are shown to remain consistent as the grid is refined.

  12. Advanced turbine systems: Studies and conceptual design

    SciTech Connect

    van der Linden, S.; Gnaedig, G.; Kreitmeier, F.

    1993-11-01

    The ABB selection for the Advanced Turbine System (ATS) includes advanced developments especially in the hot gas path of the combustion turbine and new state-of-the-art units such as the steam turbine and the HRSG. The increase in efficiency by more than 10% multiplicative compared to current designs will be based on: (1) Turbine Inlet Temperature Increase; (2) New Cooling Techniques for Stationary and Rotating Parts; and New Materials. Present, projected component improvements that will be introduced with the above mentioned issues will yield improved CCSC turbine performance, which will drive the ATS selected gas-fired reference CC power plant to 6 % LHV or better. The decrease in emission levels requires a careful optimization of the cycle design, where cooling air consumption has to be minimized. All interfaces of the individual systems in the complete CC Plant need careful checks, especially to avoid unnecessary margins in the individual designs. This study is an important step pointing out the feasibility of the ATS program with realistic goals set by DOE, which, however, will present challenges for Phase II time schedule of 18 months. With the approach outlined in this study and close cooperation with DOE, ATS program success can be achieved to deliver low emissions and low cost of electricity by the year 2002. The ABB conceptual design and step approach will lead to early component demonstration which will help accelerate the overall program objectives.

  13. Liquid belt radiator design study

    NASA Technical Reports Server (NTRS)

    Teagan, W. P.; Fitzgerald, K. F.

    1986-01-01

    The Liquid Belt Radiator (LBR) is an advanced concept developed to meet the needs of anticipated future space missions. A previous study documented the advantages of this concept as a lightweight, easily deployable alternative to present day space heat rejection systems. The technical efforts associated with this study concentrate on refining the concept of the LBR as well as examining the issues of belt dynamics and potential application of the LBR to intermediate and high temperature heat rejection applications. A low temperature point design developed in previous work is updated assuming the use of diffusion pump oil, Santovac-6, as the heat transfer media. Additional analytical and design effort is directed toward determining the impact of interface heat exchanger, fluid bath sealing, and belt drive mechanism designs on system performance and mass. The updated design supports the earlier result by indicating a significant reduction in system specific system mass as compared to heat pipe or pumped fluid radiator concepts currently under consideration (1.3 kg/sq m versus 5 kg/sq m).

  14. National accounts manager: Design study. Final report

    SciTech Connect

    Waggoner, J.

    1998-09-01

    This document addresses a typical application -- that of a hypothetical nationwide chain of restaurants. The design study uses the Reference Model for Open Distributed Processing (RM-ODP) as a guideline for specifying standard systems. Far from limiting the study`s usefulness to a particular type of National Account, this guideline is highly portable, and will be useful, with slight modifications only, in similarly specifying systems for other types of customers. A brief list of other applications could include many ``campus`` environments -- government agencies and university systems as well as manufacturers, airports, railyards, ski resorts, apartment complexes, hotels, hospitals, telecommunication facilities, oil fields, irrigation systems, municipal water/sewer systems, and so on.

  15. Reference Pricing System and Competition: Case Study from Portugal

    PubMed Central

    Portela, Conceiçăo

    2009-01-01

    Aim To characterize the patterns of competition for a sample of drugs in the Portuguese pharmaceutical market before (January 2002-March 2003) and after (April 2003-June 2003) the introduction of the reference pricing system (RPS). Methods We performed a descriptive, retrospective, longitudinal analysis, with monthly observations from January 2002 until June 2003 of 15 homogeneous groups. The groups represented the upper limit of public pharmaceutical expenditure in the RPS segment in 2003 (n = 270). Measures of competition were: 1) number of presentations; 2) prescriptions’ concentration in the generic and originator (brand) segments, using Herfindahl-Hirschman Index (HHI); and 3) dominant positions of market leader in the homogeneous group. A correlation analysis between the number of presentations, the HHI, and the dominant position of the market leader was performed using Pearson coefficient of correlation. Results The structure of the market changed with the introduction of RPS. We found an increasing number of generic presentations (from 4 ± 3 to 7 ± 4; mean ± standard deviation) and a decrease in the HHI for the generics market segment (from 0.7 ± 0.2 to 0.6 ± 0.3). There was a negative correlation between those variables that increased after the introduction of RPS (from -0.6 to -0.8). The HHI for brands and the dominant positions remained unchanged. Conclusion After the implementation of RPS, the increased competition was mainly driven by economic and social agents in the generics market segment but not in the brands market segment. PMID:19839066

  16. Design and analysis strategies for digital repetitive control systems with time-varying reference/disturbance period

    NASA Astrophysics Data System (ADS)

    Costa-Castelló, R.; Olm, J. M.; Ramos, G. A.

    2011-07-01

    This article analyses stability and performance features of different design schemes for digital repetitive control systems subject to references/disturbances that exhibit non-uniform frequency. Aiming at maintaining a constant value for the ratio T p /T s , T p being the period of the reference/disturbance signal and T s being the sampling period, two approaches are proposed. The first one deals with the real-time adaptation of T s to the actual changes of T p ; stability is studied by means of an LMI gridding method and also using robust control techniques. The second one propounds the introduction of an additional compensator that annihilates the effect of the time-varying sampling in the closed-loop system and forces its behaviour to coincide with that of an a priori selected nominal sampling period; the internal stability of the compensator-plant subsystem is checked by means of LMI gridding. The theoretical results are experimentally tested and compared through a mechatronic plant model.

  17. Reference (Axially Graded) Low Enriched Uranium Fuel Design for the High Flux Isotope Reactor (HFIR)

    SciTech Connect

    Ilas, Germina; Primm, Trent

    2010-01-01

    During the past five years, staff at the Oak Ridge National Laboratory (ORNL) have studied the issue of whether the HFIR could be converted to low enriched uranium (LEU) fuel without degrading the performance of the reactor. Using state-of-the-art reactor physics methods and behind-the-state-of-the-art thermal hydraulics methods, the staff have developed fuel plate designs (HFIR uses two types of fuel plates) that are believed to meet physics and thermal hydraulic criteria provided the reactor power is increased from 85 to 100 MW. The paper will present a defense of the results by explaining the design and validation process. A discussion of the requirements for showing applicability of analyses to approval for loading the fuel to HFIR lead test core irradiation currently scheduled for 2016 will be provided. Finally, the potential benefits of upgrading thermal hydraulics methods will be discussed.

  18. A global reference for caesarean section rates (C-Model): a multicountry cross-sectional study

    PubMed Central

    Souza, JP; Betran, AP; Dumont, A; de Mucio, B; Gibbs Pickens, CM; Deneux-Tharaux, C; Ortiz-Panozo, E; Sullivan, E; Ota, E; Togoobaatar, G; Carroli, G; Knight, H; Zhang, J; Cecatti, JG; Vogel, JP; Jayaratne, K; Leal, MC; Gissler, M; Morisaki, N; Lack, N; Oladapo, OT; Tunçalp, Ö; Lumbiganon, P; Mori, R; Quintana, S; Costa Passos, AD; Marcolin, AC; Zongo, A; Blondel, B; Hernández, B; Hogue, CJ; Prunet, C; Landman, C; Ochir, C; Cuesta, C; Pileggi-Castro, C; Walker, D; Alves, D; Abalos, E; Moises, ECD; Vieira, EM; Duarte, G; Perdona, G; Gurol-Urganci, I; Takahiko, K; Moscovici, L; Campodonico, L; Oliveira-Ciabati, L; Laopaiboon, M; Danansuriya, M; Nakamura-Pereira, M; Costa, ML; Torloni, MR; Kramer, MR; Borges, P; Olkhanud, PB; Pérez-Cuevas, R; Agampodi, SB; Mittal, S; Serruya, S; Bataglia, V; Li, Z; Temmerman, M; Gülmezoglu, AM

    2016-01-01

    Objective To generate a global reference for caesarean section (CS) rates at health facilities. Design Cross-sectional study. Setting Health facilities from 43 countries. Population/Sample Thirty eight thousand three hundred and twenty-four women giving birth from 22 countries for model building and 10 045 875 women giving birth from 43 countries for model testing. Methods We hypothesised that mathematical models could determine the relationship between clinical-obstetric characteristics and CS. These models generated probabilities of CS that could be compared with the observed CS rates. We devised a three-step approach to generate the global benchmark of CS rates at health facilities: creation of a multi-country reference population, building mathematical models, and testing these models. Main outcome measures Area under the ROC curves, diagnostic odds ratio, expected CS rate, observed CS rate. Results According to the different versions of the model, areas under the ROC curves suggested a good discriminatory capacity of C-Model, with summary estimates ranging from 0.832 to 0.844. The C-Model was able to generate expected CS rates adjusted for the case-mix of the obstetric population. We have also prepared an e-calculator to facilitate use of C-Model (www.who.int/reproductivehealth/publications/maternal_perinatal_health/c-model/en/). Conclusions This article describes the development of a global reference for CS rates. Based on maternal characteristics, this tool was able to generate an individualised expected CS rate for health facilities or groups of health facilities. With C-Model, obstetric teams, health system managers, health facilities, health insurance companies, and governments can produce a customised reference CS rate for assessing use (and overuse) of CS. PMID:26259689

  19. Heat source reentry vehicle design study

    NASA Technical Reports Server (NTRS)

    Ryan, R. L.

    1971-01-01

    The design details are presented of a flight-type heat source reentry vehicle and heat exchanger compatible with the isotope Brayton power conversion system. The reference reentry vehicle and heat exchanger were modified, orbital and superorbital capability was assessed, and a complete set of detail design layout drawings were provided.

  20. Towards a reference cavitating vessel Part III—design and acoustic pressure characterization of a multi-frequency sonoreactor

    NASA Astrophysics Data System (ADS)

    Wang, Lian; Memoli, Gianluca; Hodnett, Mark; Butterworth, Ian; Sarno, Dan; Zeqiri, Bajram

    2015-08-01

    A multi-frequency cavitation vessel (RV-multi) has been commissioned at the National Physical Laboratory (NPL, UK), with the aim of establishing a standard source of acoustic cavitation in water, with reference to which details of the cavitation process can be studied and cavitation measurement techniques evaluated. The vessel is a cylindrical cavity with a maximum capacity up to 17 L, and is designed to work at six frequency ranges, from 21 kHz to 136 kHz, under controlled temperature conditions. This paper discusses the design of RV-multi and reports experiments carried out to establish the reproducibility of the acoustic pressure field established within the vessel and its operating envelope, including sensitivity to aspects such as water depth and temperature. The acoustic field distribution was determined along the radial and depth directions within the vessel using a miniature hydrophone, for two input voltage levels under low power transducer excitation conditions (e.g. below the cavitation threshold). Particular care was taken in determining peak acoustic pressure locations, as these are critical for accompanying cavitation studies. Perturbations of the vessel by the measuring hydrophone were also monitored with a bottom-mounted pressure sensor.

  1. Warm gas TVC design study

    NASA Technical Reports Server (NTRS)

    Moorhead, S. B., Jr.

    1973-01-01

    A warm gas thrust vector control system was studied to optimize the injection geometry for a specific engine configuration, and an injection valve was designed capable of meeting the base line requirements. To optimize injection geometry, studies were made to determine the performance effects of varying injection location, angle, port size, and port configuration. Having minimized the injection flow rate required, a warm gas valve was designed to handle the required flow. A direct drive hydraulic servovalve capable of operating with highly contaminated hydraulic fluid was designed. The valve is sized to flow 15 gpm at 3000 psia and the direct drive feature is capable of applying a spool force of 200 pounds. The baseline requirements are the development of 6 deg of thrust vector control utilizing 2000 F (total temperature) gas for 180 seconds on a 1.37 million pound thrust engine burning LOX and RP-1 at a chamber pressure of 250 psia with a 155 inch long conical nozzle having a 68 inch diameter throat and a 153 inch diameter exit.

  2. Supersonic airplane study and design

    NASA Technical Reports Server (NTRS)

    Cheung, Samson

    1993-01-01

    A supersonic airplane creates shocks which coalesce and form a classical N-wave on the ground, forming a double bang noise termed sonic boom. A recent supersonic commercial transport (the Concorde) has a loud sonic boom (over 100 PLdB) and low aerodynamic performance (cruise lift-drag ratio 7). To enhance the U.S. market share in supersonic transport, an airframer's market risk for a low-boom airplane has to be reduced. Computational fluid dynamics (CFD) is used to design airplanes to meet the dual constraints of low sonic boom and high aerodynamic performance. During the past year, a research effort was focused on three main topics. The first was to use the existing design tools, developed in past years, to design one of the low-boom wind-tunnel configurations (Ames Model 3) for testing at Ames Research Center in April 1993. The second was to use a Navier-Stokes code (Overflow) to support the Oblique-All-Wing (OAW) study at Ames. The third was to study an optimization technique applied on a Haack-Adams body to reduce aerodynamic drag.

  3. Lunar astronomical observatories - Design studies

    NASA Technical Reports Server (NTRS)

    Johnson, Stewart W.; Burns, Jack O.; Chua, Koon Meng; Duric, Nebojsa; Gerstle, Walter H.

    1990-01-01

    The best location in the inner solar system for the grand observatories of the 21st century may be the moon. A multidisciplinary team including university students and faculty in engineering, astronomy, physics, and geology, and engineers from industry is investigating the moon as a site for astronomical observatories and is doing conceptual and preliminary designs for these future observatories. Studies encompass lunar facilities for radio astronomy and astronomy at optical, ultraviolet, and infrared wavelengths of the electromagnetic spectrum. Although there are significant engineering challenges in design and construction on the moon, the rewards for astronomy can be great, such as detection and study of earth-like planets orbiting nearby stars, and the task for engineers promises to stimulate advances in analysis and design, materials and structures, automation and robotics, foundations, and controls. Fabricating structures in the reduced-gravity environment of the moon will be easier than in the zero-gravity environment of earth orbit, as Apollo and space-shuttle missions have revealed. Construction of observatories on the moon can be adapted from techniques developed on the earth, with the advantage that the moon's weaker gravitational pull makes it possible to build larger devices than are practical on earth.

  4. Overview of the STARFIRE reference commercial tokamak fusion power reactor design

    SciTech Connect

    Baker, C.C.; Abdou, M.A.; DeFreece, D.A.; Trachsel, C.A.; Graumann, D.; Barry, K.

    1980-01-01

    The purpose of the STARFIRE study is to develop a design concept for a commercial tokamak fusion electric power plant based on the deuterium/tritium/lithium fuel cycle. The major features for STARFIRE include a steady-state operating mode based on a continuous rf lower-hybrid current drive and auxiliary heating, solid tritium breeder material, pressurized water cooling, limiter/vacuum system for impurity control and exhaust, high tritium burnup, superconducting EF coils outside the TF superconducting coils, fully remote maintenance, and a low-activation shield.

  5. Using DOE Commercial Reference Buildings for Simulation Studies: Preprint

    SciTech Connect

    Field, K.; Deru, M.; Studer, D.

    2010-08-01

    The U.S. Department of Energy developed 256 EnergyPlus models for use in studies that aim to characterize about 70% of the U.S. commercial building stock. Sixteen building types - including restaurants, health care, schools, offices, supermarkets, retail, lodging, and warehouses - are modeled across 16 cities to represent the diversity of U.S. climate zones. Weighting factors have been developed to combine the models in proportions similar to those of the McGraw-Hill Construction Projects Starts Database for 2003-2007. This paper reviews the development and contents of these models and their applications in simulation studies.

  6. Superior cross-species reference genes: a blueberry case study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The advent of affordable Next Generation Sequencing technologies has had major impact on studies of many crop species, where access to genomic technologies and genome-scale data sets has been extremely limited until now. The recent development of genomic resources in blueberry will enable the applic...

  7. Design Evolution Study - Aging Options

    SciTech Connect

    P. McDaniel

    2002-04-05

    The purpose of this study is to identify options and issues for aging commercial spent nuclear fuel received for disposal at the Yucca Mountain Mined Geologic Repository. Some early shipments of commercial spent nuclear fuel to the repository may be received with high-heat-output (younger) fuel assemblies that will need to be managed to meet thermal goals for emplacement. The capability to age as much as 40,000 metric tons of heavy metal of commercial spent nuclear he1 would provide more flexibility in the design to manage this younger fuel and to decouple waste receipt and waste emplacement. The following potential aging location options are evaluated: (1) Surface aging at four locations near the North Portal; (2) Subsurface aging in the permanent emplacement drifts; and (3) Subsurface aging in a new subsurface area. The following aging container options are evaluated: (1) Complete Waste Package; (2) Stainless Steel inner liner of the waste package; (3) Dual Purpose Canisters; (4) Multi-Purpose Canisters; and (5) New disposable canister for uncanistered commercial spent nuclear fuel. Each option is compared to a ''Base Case,'' which is the expected normal waste packaging process without aging. A Value Engineering approach is used to score each option against nine technical criteria and rank the options. Open issues with each of the options and suggested future actions are also presented. Costs for aging containers and aging locations are evaluated separately. Capital costs are developed for direct costs and distributable field costs. To the extent practical, unit costs are presented. Indirect costs, operating costs, and total system life cycle costs will be evaluated outside of this study. Three recommendations for aging commercial spent nuclear fuel--subsurface, surface, and combined surface and subsurface are presented for further review in the overall design re-evaluation effort. Options that were evaluated but not recommended are: subsurface aging in a new

  8. A pragmatic approach to the design of population pharmacokinetic studies.

    PubMed

    Roy, Amit; Ette, Ene I

    2005-01-01

    The publication of a seminal article on nonlinear mixed-effect modeling led to a revolution in pharmacokinetics (PKs) with the introduction of the population approach. Since then, interest in obtaining accurate and precise estimates of population PK parameters has led to work on population PK study design that extended previous work on optimal sampling designs for individual PK parameter estimation. The issues and developments in the design of population PK studies are reviewed as a prelude to investigating, via simulation, the performance of 2 approaches (population Fisher information matrix D-optimal design and informative block [profile] randomized [IBR] design) for designing population PK studies. The results of our simulation study indicate that the designs based on the 2 approaches yielded efficient parameter estimates. The designs based on the 2 approaches performed similarly, and in some cases designs based on the IBR approach were slightly better. The ease with which the IBR designs can be generated makes them preferable in drug development, where pragmatism and time are of great consideration. We, therefore, refer to the IBR designs as pragmatic designs. Pragmatic designs that achieve high efficiency in the estimation parameters should be used in the design of population PK studies, and simulation should be used to determine the efficiency of the designs. PMID:16353920

  9. Clinicopathological study of rhinosporidiosis with special reference to cytodiagnosis

    PubMed Central

    Sinha, Anuradha; Phukan, Jyoti P; Bandyopadhyay, Gautam; Sengupta, Sanjay; Bose, Kingshuk; Mondal, Rajib K; Choudhuri, Manoj K

    2012-01-01

    Background: Rhinosporidiosis is a chronic infective disorder caused by Rhinosporidium seeberi. It usually presents as a soft polypoidal pedunculated or sessile mass. Nose and nasopharynx are the commonest sites, followed by conjunctiva, maxillary sinuses, penis, urethra. Aims: The aim of this study is to present the clinicopathological features of rhinosporidiosis in a large series of cases and to asses the role of cytology in diagnosis. Materials and Methods: 63 cases were included in the study group. Diagnosis of rhinosporidiosis was confirmed in all cases by histology with or without cytological evaluation. May-Grünwald-Giemsa and hematoxylin and eosin (H and E) staining was used in all cases, and special stains like periodic acid Schiff and mucicarmine were used in a few cases. Detailed clinical history of all the cases was noted. Routine hematological investigations including ABO blood grouping were done in all possible cases. Results: Evaluation of the clinical data in our series demonstrated male predominance (36 out of 63; 56%). Nose and nasopharynx were the commonest sites involved (74.6%). Routine hematology tests did not show any significant change in most of the cases. However, a significant proportion of the study population (18 out of 41; 44%) had blood group O. Cytodiagnosis attempted in 17 cases out of 63 cases achieved 100% correlation with histology. Conclusion: Morphological appearance alone in a few cases failed to give diagnosis of rhinosporidiosis. Cytology can be very helpful in diagnosis in these cases, but histology is the mainstay of diagnosis. PMID:23326028

  10. A Phobos-Deimos Mission as an Element of the NASA Mars Design Reference Architecture 5.0

    NASA Technical Reports Server (NTRS)

    Hoffman, Stephen J.

    2011-01-01

    NASA has conducted a series of mission studies over the past 25 years examining the eventual exploration of the surface of Mars by humans. The latest version of this evolutionary series of design reference missions/architectures - Design Reference Architecture 5 or DRA-5 - was completed in 2007. This paper examines the implications of including a human mission to explore the moons of Mars and teleoperate robots in various locations, but not to land the human crews on Mars, as an element of this reference architecture. Such a mission has been proposed several times during this same 25 year evolution leading up to the completion of DRA-5 primarily as a mission of testing the in-space vehicles and operations while surface vehicles and landers are under development. But such a precursor or test mission has never been explicitly included as an element of this Architecture. This paper will first summarize the key features of the DRA-5 to provide context for the remainder of the assessment. This will include a description of the in-space vehicles that would be the subject of a shakedown test during the Mars orbital mission. A decision tree will be used to illustrate the factors that will be analyzed, and the sequence in which they will be addressed, for this assessment. The factors that will be analyzed include the type of interplanetary transfer orbit (opposition class versus conjunction class), the type of parking orbit (circular versus elliptical), and the type of propulsion technology (high thrust chemical versus nuclear thermal rocket). The manner in which each of these factors impacts an individual mission will be described. In addition to the direct impact of these factors, additional considerations impacting crew health and overall programmatic outcomes will be discussed. Numerical results for each of the factors in the decision tree will be grouped with derived qualitative impacts from crew health and programmatic consideration. These quantitative and qualitative

  11. Nationwide Multicenter Reference Interval Study for 28 Common Biochemical Analytes in China

    PubMed Central

    Xia, Liangyu; Chen, Ming; Liu, Min; Tao, Zhihua; Li, Shijun; Wang, Liang; Cheng, Xinqi; Qin, Xuzhen; Han, Jianhua; Li, Pengchang; Hou, Li’an; Yu, Songlin; Ichihara, Kiyoshi; Qiu, Ling

    2016-01-01

    Abstract A nationwide multicenter study was conducted in the China to explore sources of variation of reference values and establish reference intervals for 28 common biochemical analytes, as a part of the International Federation of Clinical Chemistry and Laboratory Medicine, Committee on Reference Intervals and Decision Limits (IFCC/C-RIDL) global study on reference values. A total of 3148 apparently healthy volunteers were recruited in 6 cities covering a wide area in China. Blood samples were tested in 2 central laboratories using Beckman Coulter AU5800 chemistry analyzers. Certified reference materials and value-assigned serum panel were used for standardization of test results. Multiple regression analysis was performed to explore sources of variation. Need for partition of reference intervals was evaluated based on 3-level nested ANOVA. After secondary exclusion using the latent abnormal values exclusion method, reference intervals were derived by a parametric method using the modified Box–Cox formula. Test results of 20 analytes were made traceable to reference measurement procedures. By the ANOVA, significant sex-related and age-related differences were observed in 12 and 12 analytes, respectively. A small regional difference was observed in the results for albumin, glucose, and sodium. Multiple regression analysis revealed BMI-related changes in results of 9 analytes for man and 6 for woman. Reference intervals of 28 analytes were computed with 17 analytes partitioned by sex and/or age. In conclusion, reference intervals of 28 common chemistry analytes applicable to Chinese Han population were established by use of the latest methodology. Reference intervals of 20 analytes traceable to reference measurement procedures can be used as common reference intervals, whereas others can be used as the assay system-specific reference intervals in China. PMID:26945390

  12. Design Issues in Transgender Studies

    PubMed Central

    Emel, Lynda; Hanscom, Brett; Zangeneh, Sahar

    2016-01-01

    Abstract: Transgender individuals constitute an important focus for HIV prevention, but studies in this population present some unique methodologic and operational challenges. We consider issues related to sampling, sample size, number of sites, and trial cost. We discuss relevant design issues for evaluating interventions in both HIV-negative and HIV-infected transgender populations, as well as a method for assessing the impact of an intervention on population HIV incidence. We find that HIV-endpoint studies of transgender individuals will likely require fewer participants but more sites and have higher operational costs than HIV prevention trials in other populations. Because any intervention targeted to transgender individuals will likely include antiretroviral drugs, small scale studies looking at potential interactions between antiretroviral therapy and hormone therapy are recommended. Finally, assessing the impact of an intervention targeted to transgender individuals will require better information on the contribution of such individuals to the population HIV incidence. PMID:27429191

  13. Design Issues in Transgender Studies.

    PubMed

    Hughes, James P; Emel, Lynda; Hanscom, Brett; Zangeneh, Sahar

    2016-08-15

    Transgender individuals constitute an important focus for HIV prevention, but studies in this population present some unique methodologic and operational challenges. We consider issues related to sampling, sample size, number of sites, and trial cost. We discuss relevant design issues for evaluating interventions in both HIV-negative and HIV-infected transgender populations, as well as a method for assessing the impact of an intervention on population HIV incidence. We find that HIV-endpoint studies of transgender individuals will likely require fewer participants but more sites and have higher operational costs than HIV prevention trials in other populations. Because any intervention targeted to transgender individuals will likely include antiretroviral drugs, small scale studies looking at potential interactions between antiretroviral therapy and hormone therapy are recommended. Finally, assessing the impact of an intervention targeted to transgender individuals will require better information on the contribution of such individuals to the population HIV incidence. PMID:27429191

  14. Study designs for dependent happenings.

    PubMed

    Halloran, M E; Struchiner, C J

    1991-09-01

    In 1916, Sir Ronald Ross defined "dependent happenings" as events where the number affected in a unit of time depends on the number already affected. That is, the incidence depends on the prevalence, a characteristic of many infectious diseases. Because of this dependence, interventions against infectious diseases can have not only direct protective effects for the person receiving an intervention, but also indirect effects resulting from changes in the intensity of transmission in the population. This paper develops the conceptual framework for four types of study designs that differentiate and account for direct and indirect effects of intervention programs in dependent happenings. PMID:1742381

  15. AEROSOL PARTICLE COLLECTOR DESIGN STUDY

    SciTech Connect

    Lee, S; Richard Dimenna, R

    2007-09-27

    A computational evaluation of a particle collector design was performed to evaluate the behavior of aerosol particles in a fast flowing gas stream. The objective of the work was to improve the collection efficiency of the device while maintaining a minimum specified air throughput, nominal collector size, and minimal power requirements. The impact of a range of parameters was considered subject to constraints on gas flow rate, overall collector dimensions, and power limitations. Potential improvements were identified, some of which have already been implemented. Other more complex changes were identified and are described here for further consideration. In addition, fruitful areas for further study are proposed.

  16. The International Design Study for the Neutrino Factory

    SciTech Connect

    Long, K.

    2008-02-21

    The International Design Study for a future Neutrino Factory and super-beam facility (the ISS) established the physics case for a high-precision programme of long-baseline neutrino-oscillation measurements. The ISS also identified baseline specifications for the Neutrino Factory accelerator complex and the neutrino detector systems. This paper summarises the objectives of the International Design Study for the Neutrino Factory (the IDS-NF). The IDS-NF will build on the work of the ISS to deliver a Reference Design Report for the Neutrino Factory by 2012/13 and an Interim Design Report by 2010/11.

  17. MIUS community conceptual design study

    NASA Technical Reports Server (NTRS)

    Fulbright, B. E.

    1976-01-01

    The feasibility, practicality, and applicability of the modular integrated utility systems (MIUS) concept to a satellite new-community development with a population of approximately 100,000 were analyzed. Two MIUS design options, the 29-MIUS-unit (option 1) and the 8-MIUS-unit (option 2) facilities were considered. Each resulted in considerable resource savings when compared to a conventional utility system. Economic analyses indicated that the total cash outlay and operations and maintenance costs for these two options were considerably less than for a conventional system. Computer analyses performed in support of this study provided corroborative data for the study group. An environmental impact assessment was performed to determine whether the MIUS meets or will meet necessary environmental standards. The MIUS can provide improved efficiency in the conservation of natural resources while not adversely affecting the physical environment.

  18. H2FIRST Reference Station Design Task: Project Deliverable 2-2

    SciTech Connect

    Pratt, Joseph; Terlip, Danny; Ainscough, Chris; Kurtz, Jennifer; Elgowainy, Amgad

    2015-04-20

    This report presents near-term station cost results and discusses cost trends of different station types. It compares various vehicle rollout scenarios and projects realistic near-term station utilization values using the station infrastructure rollout in California as an example. It describes near-term market demands and matches those to cost-effective station concepts. Finally, the report contains detailed designs for five selected stations, which include piping and instrumentation diagrams, bills of materials, and several site-specific layout studies that incorporate the setbacks required by NFPA 2, the National Fire Protection Association Hydrogen Technologies Code. This work identified those setbacks as a significant factor affecting the ability to site a hydrogen station, particularly liquid stations at existing gasoline stations. For all station types, utilization has a large influence on the financial viability of the station.

  19. 40 CFR 53.8 - Designation of reference and equivalent methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... satisfy the applicable requirements of this part shall be designated as a FRM or FEM (as applicable) by... notice indicating that the method has been designated as a FRM or FEM shall be sent to the applicant. (c) The Administrator will maintain a current list of methods designated as FRM or FEM in accordance...

  20. 40 CFR 53.8 - Designation of reference and equivalent methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... satisfy the applicable requirements of this part shall be designated as a FRM or FEM (as applicable) by... notice indicating that the method has been designated as a FRM or FEM shall be sent to the applicant. (c) The Administrator will maintain a current list of methods designated as FRM or FEM in accordance...

  1. Anaphoric reference to quantified antecedents: an event-related brain potential study.

    PubMed

    Filik, Ruth; Leuthold, Hartmut; Moxey, Linda M; Sanford, Anthony J

    2011-11-01

    We report an event-related brain potential (ERP) study examining how readers process sentences containing anaphoric reference to quantified antecedents. Previous studies indicate that positive (e.g. many) and negative (e.g. not many) quantifiers cause readers to focus on different sets of entities. For example in Many of the fans attended the game, focus is on the fans who attended (the reference set), and subsequent pronominal reference to this set, as in, Their presence was a boost to the team, is facilitated. In contrast, if many is replaced by not many, focus shifts to the fans who did not attend (the complement set), and reference to this set, as in, Their absence was disappointing, is preferred. In the current studies, the electroencephalogram (EEG) was recorded while participants read positive or negative quantified statements followed by anaphoric reference to the reference set or complement set. Results showed that the pronoun their elicited a larger N400 following negative than positive quantifiers. There was also a larger N400 on the disambiguating word (presence/absence) for complement set reference following a positive quantifier, and for reference set reference following a negative quantifier. Findings are discussed in relation to theoretical accounts of complement anaphora. PMID:21986293

  2. Design and assembly sequence analysis of option 3 for CETF reference space station

    NASA Technical Reports Server (NTRS)

    Garrett, L. Bernard; Andersen, Gregory C.; Hall, John B., Jr.; Allen, Cheryl L.; Scott, A. D., Jr.; So, Kenneth T.

    1987-01-01

    A design and assembly sequence was conducted on one option of the Dual Keel Space Station examined by a NASA Critical Evaluation Task Force to establish viability of several variations of that option. A goal of the study was to produce and analyze technical data to support Task Force decisions to either examine particular Option 3 variations in more depth or eliminate them from further consideration. An analysis of the phasing assembly showed that use of an Expendable Launch Vehicle in conjunction with the Space Transportation System (STS) can accelerate the buildup of the Station and ease the STS launch rate constraints. The study also showed that use of an Orbital Maneuvering Vehicle on the first flight can significantly benefit Station assembly and, by performing Station subsystem functions, can alleviate the need for operational control and reboost systems during the early flights. In addition to launch and assembly sequencing, the study assessed stability and control, and analyzed node-packaging options and the effects of keel removal on the structural dynamics of the Station. Results of these analyses are presented and discussed.

  3. The Mobile Reference Service: a case study of an onsite reference service program at the School of Public Health.

    PubMed

    Tao, Donghua; McCarthy, Patrick G; Krieger, Mary M; Webb, Annie B

    2009-01-01

    The School of Public Health at Saint Louis University is located at a greater distance from the library than other programs on the main medical center campus. Physical distance diminishes the ease of access to direct reference services for public health users. To bridge the gap, the library developed the Mobile Reference Service to deliver on-site information assistance with regular office hours each week. Between September 2006 and April 2007, a total of 57 in-depth reference transactions took place over 25 weeks, averaging 2 transactions per week in a 2-hour period. Overall reference transactions from public health users went up 28%, while liaison contacts with public health users doubled compared to the same period the year before. The Mobile Reference Service program has improved library support for research and scholarship, cultivated and strengthened liaison relationships, and enhanced marketing and delivery of library resources and services to the Saint Louis University School of Public Health. PMID:19159004

  4. Design implementation and control of MRAS error dynamics. [Model-Reference Adaptive System

    NASA Technical Reports Server (NTRS)

    Colburn, B. K.; Boland, J. S., III

    1974-01-01

    Use is made of linearized error characteristic equation for model-reference adaptive systems to determine a parameter adjustment rule for obtaining time-invariant error dynamics. Theoretical justification of error stability is given and an illustrative example included to demonstrate the utility of the proposed technique.

  5. a Study on Producing Highly Reliabile Reference Data Sets for Global Land Cover Validation

    NASA Astrophysics Data System (ADS)

    Soyama, N.; Muramatsu, K.; Daigo, M.; Ochiai, F.; Fujiwara, N.

    2016-06-01

    Validating the accuracy of land cover products using a reliable reference dataset is an important task. A reliable reference dataset is produced with information derived from ground truth data. Recently, the amount of ground truth data derived from information collected by volunteers has been increasing globally. The acquisition of volunteer-based reference data demonstrates great potential. However information given by volunteers is limited useful vegetation information to produce a complete reference dataset based on the plant functional type (PFT) with five specialized forest classes. In this study, we examined the availability and applicability of FLUXNET information to produce reference data with higher levels of reliability. FLUXNET information was useful especially for forest classes for interpretation in comparison with the reference dataset using information given by volunteers.

  6. Mars Global Reference Atmospheric Model (Mars-GRAM) and Database for Mission Design

    NASA Technical Reports Server (NTRS)

    Justus, C. G.; Duvall, Aleta; Johnson, D. L.

    2003-01-01

    Mars Global Reference Atmospheric Model (Mars-GRAM 2001) is an engineering-level Mars atmosphere model widely used for many Mars mission applications. From 0-80 km, it is based on NASA Ames Mars General Circulation Model, while above 80 km it is based on Mars Thermospheric General Circulation Model. Mars-GRAM 2001 and MGCM use surface topography from Mars Global Surveyor Mars Orbiting Laser Altimeter. Validation studies are described comparing Mars-GRAM with Mars Global Surveyor Radio Science and Thermal Emission Spectrometer data. RS data from 2480 profiles were used, covering latitudes 75 deg S to 72 deg N, surface to approximately 40 km, for seasons ranging from areocentric longitude of Sun (Ls) = 70-160 deg and 265-310 deg. RS data spanned a range of local times, mostly 0-9 hours and 18-24 hours. For interests in aerocapture and precision landing, comparisons concentrated on atmospheric density. At a fixed height of 20 km, RS density varied by about a factor of 2.5 over ranges of latitudes and Ls values observed. Evaluated at matching positions and times, these figures show average RSMars-GRAM density ratios were generally 1+/-)0.05, except at heights above approximately 25 km and latitudes above approximately 50 deg N. Average standard deviation of RSMars-GRAM density ratio was 6%. TES data were used covering surface to approximately 40 km, over more than a full Mars year (February, 1999 - June, 2001, just before start of a Mars global dust storm). Depending on season, TES data covered latitudes 85 deg S to 85 deg N. Most TES data were concentrated near local times 2 hours and 14 hours. Observed average TES/Mars-GRAM density ratios were generally 1+/-0.05, except at high altitudes (15-30 km, depending on season) and high latitudes (greater than 45 deg N), or at most altitudes in the southern hemisphere at Ls approximately 90 and 180 deg. Compared to TES averages for a given latitude and season, TES data had average density standard deviation about the mean of

  7. Essentials of College and University Accounting: A Reference Companion to NACUBO's Online Self-Study Course

    ERIC Educational Resources Information Center

    National Association of College and University Business Officers (NJ3), 2006

    2006-01-01

    This reference guide presents the basic accounting concepts, terminology, and definitions used by colleges and universities. The guide, a companion to the National Association of College and University Business Officers' (NACUBO's) online self-study course of the same name or a standalone reference, compares college and university accounting…

  8. The Study Skills Component of the Wisconsin Design.

    ERIC Educational Resources Information Center

    Kamm, Karlyn

    Initial development of the list of skills and related behavioral objectives in the study skills area of The Wisconsin Design for Reading Skill Development began with an extensive search. As an organizational framework, the area was divided into three subareas: maps, graphs and tables, and reference skills. The professional literature,…

  9. Proposed Reference Spectral Irradiance Standards to Improve Photovoltaic Concentrating System Design and Performance Evaluation: Preprint

    SciTech Connect

    Myers, D. R.; Emery, K. E.; Gueymard, C.

    2002-05-01

    This conference paper describes the American Society for Testing and Materials (ASTM), the International Electrotechnical Commission (IEC), and the International Standards Organization (ISO) standard solar terrestrial spectra (ASTM G-159, IEC-904-3, ISO 9845-1) provide standard spectra for photovoltaic performance applications. Modern terrestrial spectral radiation models and knowledge of atmospheric physics are applied to develop suggested revisions to update the reference spectra. We use a moderately complex radiative transfer model (SMARTS2) to produce the revised spectra. SMARTS2 has been validated against the complex MODTRAN radiative transfer code and spectral measurements. The model is proposed as an adjunct standard to reproduce the reference spectra. The proposed spectra represent typical clear sky spectral conditions associated with sites representing reasonable photovoltaic energy production and weathering and durability climates. The proposed spectra are under consideration by ASTM.

  10. Development and Evaluation of Reference Standards for Image-based Telemedicine Diagnosis and Clinical Research Studies in Ophthalmology

    PubMed Central

    Ryan, Michael C.; Ostmo, Susan; Jonas, Karyn; Berrocal, Audina; Drenser, Kimberly; Horowitz, Jason; Lee, Thomas C.; Simmons, Charles; Martinez-Castellanos, Maria-Ana; Chan, R.V. Paul; Chiang, Michael F.

    2014-01-01

    Information systems managing image-based data for telemedicine or clinical research applications require a reference standard representing the correct diagnosis. Accurate reference standards are difficult to establish because of imperfect agreement among physicians, and discrepancies between clinical vs. image-based diagnosis. This study is designed to describe the development and evaluation of reference standards for image-based diagnosis, which combine diagnostic impressions of multiple image readers with the actual clinical diagnoses. We show that agreement between image reading and clinical examinations was imperfect (689 [32%] discrepancies in 2148 image readings), as was inter-reader agreement (kappa 0.490-0.652). This was improved by establishing an image-based reference standard defined as the majority diagnosis given by three readers (13% discrepancies with image readers). It was further improved by establishing an overall reference standard that incorporated the clinical diagnosis (10% discrepancies with image readers). These principles of establishing reference standards may be applied to improve robustness of real-world systems supporting image-based diagnosis. PMID:25954463

  11. Novel Compressor Blade Design Study

    NASA Astrophysics Data System (ADS)

    Srinivas, Abhay

    Jet engine efficiency goals are driving compressors to higher pressure ratios and engines to higher bypass ratios, each one driving to smaller cores. This is leading to larger tip gaps relative to the blade height. These larger relative tip clearances would negate some of the cycle improvements, and ways to mitigate this effect must be found. A novel split tip blade geometry has been created which helps improve the efficiency at large clearances while also improving operating range. Two identical blades are leaned in opposite directions starting at 85% span. They are cut at mid chord and the 2 halves then merged together so a split tip is created. The result is similar to the alula feathers on a soaring bird. The concept is that the split tip will energize the tip flow and increase range. For higher relative tip clearance, this will also improve efficiency. The 6th rotor of a highly loaded 10 stage machine was chosen as the baseline for this study. Three dimensional CFD simulations were performed using CD Adapco's Star-CCM+ at 5 clearances for the baseline and split tip geometry. The choking flow and stall margin of the split tip blade was higher than that of the baseline blade for all tip clearances. The pressure ratio of the novel blade was higher than that of the baseline blade near choke, but closer to stall it decreased. The sensitivity of peak efficiency to clearance was improved. At tight clearances of 0.62% of blade height, the maximum efficiency of the new design was less than the baseline blade, but as the tip clearance was increased above 2.5%, the maximum efficiency increased. Structural analysis was also performed to ascertain the feasibility of the design.

  12. Take A Trip Reference Manual: An Authoring and Storage System for Designing and Sharing Challenging Curriculum.

    ERIC Educational Resources Information Center

    Minnesota State Dept. of Education, St. Paul. Evaluation Section.

    The Take a Trip program is an authoring and storage system for designing challenging curriculum. Using the power of hypermedia, specifically Apple Computer's HyperCard, Take a Trip provides course file stacks, help stacks, and personalized learning plan stacks. Designed to assist the user when new units are written, the help stacks provide an…

  13. Power Requirements for The NASA Mars Design Reference Architecture (DRA) 5.0

    NASA Technical Reports Server (NTRS)

    Cataldo, Robert L.

    2009-01-01

    This paper summarizes the power systems analysis results from NASA s recent Mars DRA 5.0 study which examined three architecture options and resulting mission requirements for a human Mars landing mission in the post-2030 timeframe. DRA 5.0 features a long approximately 500 day surface stay split mission using separate cargo and crewed Mars transfer vehicles. Two cargo flights, utilizing minimum energy trajectories, pre-deploy a cargo lander to the surface and a habitat lander into a 24-hour elliptical Mars parking orbit where it remains until the arrival of the crew during the next mission opportunity approximately 26 months later. The pre-deployment of cargo poses unique challenges for set-up and emplacement of surface assets that results in the need for self or robotically deployed designs. Three surface architecture options were evaluated for breadth of science content, extent of exploration range/capability and variations in system concepts and technology. This paper describes the power requirements for the surface operations of the three mission options, power system analyses including discussion of the nuclear fission, solar photovoltaic and radioisotope concepts for main base power and long range mobility.

  14. Radioactive waste isolation in salt: peer review of Westinghouse Electric Corporation's report on reference conceptual designs for a repository waste package

    SciTech Connect

    Rote, D.M.; Hull, A.B.; Was, G.S.; Macdonald, D.D.; Wilde, B.E.; Russell, J.E.; Kruger, J.; Harrison, W.; Hambley, D.F.

    1985-10-01

    This report documents the findings of the peer panel constituted by Argonne National Laboratory to review Region A of Westinghouse Electric Corporation's report entitled Waste Package Reference Conceptual Designs for a Repository in Salt. The panel determined that the reviewed report does not provide reasonable assurance that US Nuclear Regulatory Commission (NRC) requirements for waste packages will be met by the proposed design. It also found that it is premature to call the design a ''reference design,'' or even a ''reference conceptual design.'' This review report provides guidance for the preparation of a more acceptable design document.

  15. Agreement between diagnoses reached by clinical examination and available reference standards: a prospective study of 216 patients with lumbopelvic pain

    PubMed Central

    Laslett, Mark; McDonald, Barry; Tropp, Hans; Aprill, Charles N; Öberg, Birgitta

    2005-01-01

    Background The tissue origin of low back pain (LBP) or referred lower extremity symptoms (LES) may be identified in about 70% of cases using advanced imaging, discography and facet or sacroiliac joint blocks. These techniques are invasive and availability varies. A clinical examination is non-invasive and widely available but its validity is questioned. Diagnostic studies usually examine single tests in relation to single reference standards, yet in clinical practice, clinicians use multiple tests and select from a range of possible diagnoses. There is a need for studies that evaluate the diagnostic performance of clinical diagnoses against available reference standards. Methods We compared blinded clinical diagnoses with diagnoses based on available reference standards for known causes of LBP or LES such as discography, facet, sacroiliac or hip joint blocks, epidurals injections, advanced imaging studies or any combination of these tests. A prospective, blinded validity design was employed. Physiotherapists examined consecutive patients with chronic lumbopelvic pain and/or referred LES scheduled to receive the reference standard examinations. When diagnoses were in complete agreement regardless of complexity, "exact" agreement was recorded. When the clinical diagnosis was included within the reference standard diagnoses, "clinical agreement" was recorded. The proportional chance criterion (PCC) statistic was used to estimate agreement on multiple diagnostic possibilities because it accounts for the prevalence of individual categories in the sample. The kappa statistic was used to estimate agreement on six pathoanatomic diagnoses. Results In a sample of chronic LBP patients (n = 216) with high levels of disability and distress, 67% received a patho-anatomic diagnosis based on available reference standards, and 10% had more than one tissue origin of pain identified. For 27 diagnostic categories and combinations, chance clinical agreement (PCC) was estimated at 13

  16. Optimal design for epidemiological studies subject to designed missingness.

    PubMed

    Morara, Michele; Ryan, Louise; Houseman, Andres; Strauss, Warren

    2007-12-01

    In large epidemiological studies, budgetary or logistical constraints will typically preclude study investigators from measuring all exposures, covariates and outcomes of interest on all study subjects. We develop a flexible theoretical framework that incorporates a number of familiar designs such as case control and cohort studies, as well as multistage sampling designs. Our framework also allows for designed missingness and includes the option for outcome dependent designs. Our formulation is based on maximum likelihood and generalizes well known results for inference with missing data to the multistage setting. A variety of techniques are applied to streamline the computation of the Hessian matrix for these designs, facilitating the development of an efficient software tool to implement a wide variety of designs. PMID:18080755

  17. Results from heater-induced quenches of A 4. 5 m Reference Design D dipole for the SSC

    SciTech Connect

    Ganetis, G.; Prodell, A.

    1986-01-01

    Quench studies were performed using a 4.5 m long Reference Design D, SSC dipole to determine the temperature rise of the magnet conductor during a quench by measuring the resistance of the conductor cable in the immediate vicinity of the quench. The single bore magnet was wound with improved NbTi conductor in a 2-layer cosine theta coil configuration of 4.0 cm inner diameter. Eight pairs of voltage taps were installed at various locations on the right side of the inner coil of the magnet. ''Spot'' heaters were centrally located between the voltage taps of 4 of these pairs on the midplane turn of the inner coil to initiate magnet quenches. A redundant array of voltage taps and heaters was also installed on the left side of the inner coil. The resistance of the conductor was obtained from observations of the current and voltage during a magnet quench. The temperature of the conductor was then determined by comparing its resistance to an R vs T curve appropriate for the conductor. The quantity ..integral.. I/sup 2/dt and the temperature, T, are presented as a function of current, and the maximum conductor temperature is shown as a function of ..integral.. I/sup 2/dt. Measured longitudinal and azimuthal quench propagation velocities are also presented as a function of magnet current, and the temperatures at several locations on the inner magnet coil are plotted as a function of the time after a quench was initiated.

  18. Design and realization of the high-precision weighing systems as the gravimetric references in PTB's national water flow standard

    NASA Astrophysics Data System (ADS)

    Engel, Rainer; Beyer, Karlheinz; Baade, Hans-Joachim

    2012-07-01

    PTB's ‘Hydrodynamic Test Field’, which represents a high-accuracy water flow calibration facility, serves as the national primary standard for liquid flow measurands. As the core reference device of this flow facility, a gravimetric standard has been incorporated, which comprises three special-design weighing systems: 300 kg, 3 tons and 30 tons. These gravimetric references were realized as a combination of a strain-gauge-based and an electromagnetic-force-compensation load-cell-based balance, each. Special emphasis had to be placed upon the dynamics design of the whole weighing system, due to the high measurement resolution and the dynamic behavior of the weighing systems, which are dynamically affected by mechanical vibrations caused by environmental impacts, flow machinery operation, flow noise in the pipework and induced wave motions in the weigh tanks. Taking into account all the above boundary conditions, the design work for the gravimetric reference resulted in a concrete foundation ‘rock’ of some 300 tons that rests on a number of vibration isolators. In addition to these passively operating vibration isolators, the vibration damping effect is enhanced by applying an electronic level regulation device.

  19. SP-100 system definition conceptual reference design activities: February through June 1983. Technical information report

    SciTech Connect

    Fortenberry, J.W.; Moore, D.M.; Petrick, S.W.; Smoak, R.H.

    1983-12-01

    The original SP-100 conceptual system design was examined from the mechanical design and integration viewpoint for the purpose of updating the design, identifying concerns, and providing recommendations for future work. Some of the findings were that: Integration of heat pipes into the radiator structure appears practical, but a number of problems remain to be addressed and resolved through development effort; thermal and structural interfacing of the shield and defining shield weight are key areas that need to be addressed; the radiator may be critical in shell buckling which would make beryllium a leading candidate material; material problems such as beryllium vs. shuttle fracture mechanics criteria need to be addressed.

  20. Gain-Scheduled Complementary Filter Design for a MEMS Based Attitude and Heading Reference System

    PubMed Central

    Yoo, Tae Suk; Hong, Sung Kyung; Yoon, Hyok Min; Park, Sungsu

    2011-01-01

    This paper describes a robust and simple algorithm for an attitude and heading reference system (AHRS) based on low-cost MEMS inertial and magnetic sensors. The proposed approach relies on a gain-scheduled complementary filter, augmented by an acceleration-based switching architecture to yield robust performance, even when the vehicle is subject to strong accelerations. Experimental results are provided for a road captive test during which the vehicle dynamics are in high-acceleration mode and the performance of the proposed filter is evaluated against the output from a conventional linear complementary filter. PMID:22163824

  1. Validation of a set of reference genes to study response to herbicide stress in grasses

    PubMed Central

    2012-01-01

    Background Non-target-site based resistance to herbicides is a major threat to the chemical control of agronomically noxious weeds. This adaptive trait is endowed by differences in the expression of a number of genes in plants that are resistant or sensitive to herbicides. Quantification of the expression of such genes requires normalising qPCR data using reference genes with stable expression in the system studied as internal standards. The aim of this study was to validate reference genes in Alopecurus myosuroides, a grass (Poaceae) weed of economic and agronomic importance with no genomic resources. Results The stability of 11 candidate reference genes was assessed in plants resistant or sensitive to herbicides subjected or not to herbicide stress using the complementary statistical methods implemented by NormFinder, BestKeeper and geNorm. Ubiquitin, beta-tubulin and glyceraldehyde-3-phosphate dehydrogenase were identified as the best reference genes. The reference gene set accuracy was confirmed by analysing the expression of the gene encoding acetyl-coenzyme A carboxylase, a major herbicide target enzyme, and of an herbicide-induced gene encoding a glutathione-S-transferase. Conclusions This is the first study describing a set of reference genes (ubiquitin, beta-tubulin and glyceraldehyde-3-phosphate dehydrogenase) with a stable expression under herbicide stress in grasses. These genes are also candidate reference genes of choice for studies seeking to identify stress-responsive genes in grasses. PMID:22233533

  2. Multiple myeloma and engine exhausts, fresh wood, and creosote: a case-referent study

    SciTech Connect

    Flodin, U.; Fredriksson, M.; Persson, B.

    1987-01-01

    The effect of potential risk factors for multiple myeloma was evaluated in a case-referent study encompassing 131 cases and 431 randomized referents, all alive. Information on exposure was obtained with questionnaires mailed to the subjects. An analysis of the material by means of the Miettinen confounder score technique resulted in a few rate ratios significantly exceeding unity--namely, occupational exposure to engine exhausts, creosote, and fresh wood. In view of other studies that suggest ionizing radiation as a risk factor, it was somewhat surprising that low-level gamma radiation from background exposure was less common among the cases than the referents.

  3. Symposium on Reference Service. Is Traditional Reference Service Obsolete? [and] Desk Set Revisited: Reference Librarians, Reality, and Research Systems' Design [and] Traditional Reference Is Dead, Now Let's Move on to Important Questions [and] Reference Service Evolved [and] Reference Service Is More than a Desk.

    ERIC Educational Resources Information Center

    Ewing, Keith; And Others

    1995-01-01

    This is a collection of five articles which suggest current and future trends in academic library reference services. The first article poses a question, and the remaining four articles offer responses to it. (DGM/JMV)

  4. Concentrator enhanced solar arrays design study

    NASA Technical Reports Server (NTRS)

    Lott, D. R.

    1978-01-01

    The analysis and preliminary design of a 25 kW concentrator enhanced lightweight flexible solar array are presented. The study was organized into five major tasks: (1) assessment and specification of design requirements; (2) mechanical design; (3) electric design; (4) concentrator design; and (5) cost projection. The tasks were conducted in an iterative manner so as to best derive a baseline design selection. The objectives of the study are discussed and comparative configurations and mass data on the SEP (Solar Electric Propulsion) array design, concentrator design options and configuration/mass data on the selected concentrator enhanced solar array baseline design are presented. Design requirements supporting design analysis and detailed baseline design data are discussed. The results of the cost projection analysis and new technology are also discussed.

  5. Genome-wide selection of superior reference genes for expression studies in Ganoderma lucidum.

    PubMed

    Xu, Zhichao; Xu, Jiang; Ji, Aijia; Zhu, Yingjie; Zhang, Xin; Hu, Yuanlei; Song, Jingyuan; Chen, Shilin

    2015-12-15

    Quantitative real-time polymerase chain reaction (qRT-PCR) is widely used for the accurate analysis of gene expression. However, high homology among gene families might result in unsuitability of reference genes, which leads to the inaccuracy of qRT-PCR analysis. The release of the Ganoderma lucidum genome has triggered numerous studies to be done on the homology among gene families with the purpose of selecting reliable reference genes. Based on the G. lucdum genome and transcriptome database, 38 candidate reference genes including 28 novel genes were systematically selected and evaluated for qRT-PCR normalization. The result indicated that commonly used polyubiquitin (PUB), beta-actin (BAT), and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) were unsuitable reference genes because of the high sequence similarity and low primer specificity. According to the evaluation of RefFinder, cyclophilin 5 (CYP5) was ranked as the most stable reference gene for 27 tested samples under all experimental conditions and eighteen mycelial samples. Based on sequence analysis and expression analysis, our study suggested that gene characteristic, primer specificity of high homologous genes, allele-specificity expression of candidate genes and under-evaluation of reference genes influenced the accuracy and sensitivity of qRT-PCR analysis. This investigation not only revealed potential factors influencing the unsuitability of reference genes but also selected the superior reference genes from more candidate genes and testing samples than those used in the previous study. Furthermore, our study established a model for reference gene analysis by using the genomic sequence. PMID:26277249

  6. Learning Science by Designing Artifacts (LSDA)--A Case Study of the Development of a Design-Based Science Curriculum.

    ERIC Educational Resources Information Center

    Mamlok, Rachel; Dershimer, Charles; Fortus, David; Krajcik, Joe; Marx, Ron

    The purpose of this study was to document the iterative development of a design-based science curriculum called Learning Science by Designing Artifacts (LSDA). The study refers to the enactment of the Safer Cell Phones curriculum in a high school located in the Midwest. The curriculum was a 5- or 9-week unit in an 18-week science elective course.…

  7. Student-Designed River Study.

    ERIC Educational Resources Information Center

    Turkall, Sheila Florian

    1996-01-01

    Describes an integrated student-designed investigation in which students explore different aspects of the Chagrin River including the river ecosystem, velocity and average depth, river flooding, water quality, and economic and political factors. (JRH)

  8. DAKOTA : a multilevel parallel object-oriented framework for design optimization, parameter estimation, uncertainty quantification, and sensitivity analysis. Version 5.0, user's reference manual.

    SciTech Connect

    Eldred, Michael Scott; Dalbey, Keith R.; Bohnhoff, William J.; Adams, Brian M.; Swiler, Laura Painton; Hough, Patricia Diane; Gay, David M.; Eddy, John P.; Haskell, Karen H.

    2010-05-01

    The DAKOTA (Design Analysis Kit for Optimization and Terascale Applications) toolkit provides a flexible and extensible interface between simulation codes and iterative analysis methods. DAKOTA contains algorithms for optimization with gradient and nongradient-based methods; uncertainty quantification with sampling, reliability, and stochastic finite element methods; parameter estimation with nonlinear least squares methods; and sensitivity/variance analysis with design of experiments and parameter study methods. These capabilities may be used on their own or as components within advanced strategies such as surrogate-based optimization, mixed integer nonlinear programming, or optimization under uncertainty. By employing object-oriented design to implement abstractions of the key components required for iterative systems analyses, the DAKOTA toolkit provides a flexible and extensible problem-solving environment for design and performance analysis of computational models on high performance computers. This report serves as a reference manual for the commands specification for the DAKOTA software, providing input overviews, option descriptions, and example specifications.

  9. DAKOTA, a multilevel parallel object-oriented framework for design optimization, parameter estimation, uncertainty quantification, and sensitivity analysis:version 4.0 reference manual

    SciTech Connect

    Griffin, Joshua D. (Sandai National Labs, Livermore, CA); Eldred, Michael Scott; Martinez-Canales, Monica L.; Watson, Jean-Paul; Kolda, Tamara Gibson; Adams, Brian M.; Swiler, Laura Painton; Williams, Pamela J.; Hough, Patricia Diane; Gay, David M.; Dunlavy, Daniel M.; Eddy, John P.; Hart, William Eugene; Guinta, Anthony A.; Brown, Shannon L.

    2006-10-01

    The DAKOTA (Design Analysis Kit for Optimization and Terascale Applications) toolkit provides a flexible and extensible interface between simulation codes and iterative analysis methods. DAKOTA contains algorithms for optimization with gradient and nongradient-based methods; uncertainty quantification with sampling, reliability, and stochastic finite element methods; parameter estimation with nonlinear least squares methods; and sensitivity/variance analysis with design of experiments and parameter study methods. These capabilities may be used on their own or as components within advanced strategies such as surrogate-based optimization, mixed integer nonlinear programming, or optimization under uncertainty. By employing object-oriented design to implement abstractions of the key components required for iterative systems analyses, the DAKOTA toolkit provides a flexible and extensible problem-solving environment for design and performance analysis of computational models on high performance computers. This report serves as a reference manual for the commands specification for the DAKOTA software, providing input overviews, option descriptions, and example specifications.

  10. Validation of Reference Genes for Expression Studies during Craniofacial Development in Arctic Charr

    PubMed Central

    Ahi, Ehsan Pashay; Guðbrandsson, Jóhannes; Kapralova, Kalina H.; Franzdóttir, Sigríður R.; Snorrason, Sigurður S.; Maier, Valerie H.; Jónsson, Zophonías O.

    2013-01-01

    Arctic charr (Salvelinus alpinus) is a highly polymorphic species and in Lake Thingvallavatn, Iceland, four phenotypic morphs have evolved. These differences in morphology, especially in craniofacial structures are already apparent during embryonic development, indicating that genes important in the formation of the craniofacial features are expressed differentially between the morphs. In order to generate tools to examine these expression differences in Arctic charr, the aim of the present study was to identify reference genes for quantitative real-time PCR (qPCR). The specific aim was to select reference genes which are able to detect very small expression differences among different morphs. We selected twelve candidate reference genes from the literature, identified corresponding charr sequences using data derived from transcriptome sequencing (RNA-seq) and examined their expression using qPCR. Many of the candidate reference genes were found to be stably expressed, yet their quality-rank as reference genes varied considerably depending on the type of analysis used. In addition to commonly used software for reference gene validation, we used classical statistics to evaluate expression profiles avoiding a bias for reference genes with similar expression patterns (co-regulation). Based on these analyses we chose three reference genes, ACTB, UB2L3 and IF5A1 for further evaluation. Their consistency was assessed in an expression study of three known craniofacially expressed genes, sparc (or osteonectin), matrix metalloprotease 2 (mmp2) and sox9 (sex-determining region Y box 9 protein) using qPCR in embryo heads derived from four charr groups at three developmental time points. The three reference genes were found to be very suitable for studying expression differences between the morphotypes, enabling robust detection of small relative expression changes during charr development. Further, the results showed that sparc and mmp2 are differentially expressed in embryos

  11. A study of commuter airplane design optimization

    NASA Technical Reports Server (NTRS)

    Roskam, J.; Wyatt, R. D.; Griswold, D. A.; Hammer, J. L.

    1977-01-01

    Problems of commuter airplane configuration design were studied to affect a minimization of direct operating costs. Factors considered were the minimization of fuselage drag, methods of wing design, and the estimated drag of an airplane submerged in a propellor slipstream; all design criteria were studied under a set of fixed performance, mission, and stability constraints. Configuration design data were assembled for application by a computerized design methodology program similar to the NASA-Ames General Aviation Synthesis Program.

  12. Protoptype integrated design (Pride) system reference manual. Volume 2: Schema definition

    NASA Technical Reports Server (NTRS)

    Fishwick, P. A.; Sutter, T. R.; Blackburn, C. L.

    1983-01-01

    An initial description of an evolving relational database schema is presented for the management of finite element model design and analysis data. The report presents a description of each relation including attribute names, data types, and definitions. The format of this report is such that future modifications and enhancements may be easily incorporated.

  13. 77 FR 32632 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-01

    ...Notice is hereby given that the Environmental Protection Agency (EPA) has designated, in accordance with 40 CFR Part 53, three new equivalent methods: One for measuring concentrations of nitrogen dioxide (NO2) and two for measuring concentrations of lead (Pb) in the ambient...

  14. An Electronic Service Quality Reference Model for Designing E-Commerce Websites Which Maximizes Customer Satisfaction

    ERIC Educational Resources Information Center

    Shaheen, Amer N.

    2011-01-01

    This research investigated Electronic Service Quality (E-SQ) features that contribute to customer satisfaction in an online environment. The aim was to develop an approach which improves E-CRM processes and enhances online customer satisfaction. The research design adopted mixed methods involving qualitative and quantitative methods to…

  15. Environmental Design and Educational Performance, with Particular Reference to "Green" Schools in Hampshire and Essex

    ERIC Educational Resources Information Center

    Edwards, Brian W.

    2006-01-01

    This article examines the argument that "green" schools enhance educational performance. Having set the context of the relationship between environmentalism and the design of schools in the twentieth century, the article explores the performance of a number of green schools built in the UK between 1980 and 1995. The aim is to discover whether…

  16. Design and performance of an arcjet nuclear electric propulsion system for a mid-1990's reference mission

    SciTech Connect

    Deininger, W.D.; Vondra, R.J.

    1987-05-01

    The design and performance of an arcjet nuclear-electric-propulsion spacecraft, suitable for use in the Space Nuclear Power System (SNPS) reference mission, are outlined. The vehicle design was based on a 30-kW ammonia arcjet system operating at an Isp of 1050 s and an efficiency of 45 percent. The arcjet/gimbal system, power-processing unit, and propellant-feed system are described. A 100-kWe SNPS was assumed, and the spacecraft mass was baselined at 5250 kg (excluding the propellant-feed system). A radiation/arcjet efflux diagnostics package was included in the performance analysis. This spacecraft, assuming a Shuttle launch from KSC, can perform a 50-deg inclination change and reach a final orbit of 35,860 km with a 120-d trip time providing a 4-mo active load for the SNPS. Alternatively, a Titan IV launch would provide a mass margin of 120 kg to a 10,000-km, 58-deg final orbit in 74 d. This spacecraft meets the reference-mission constraint of low developmental risk, and is scalable to power levels projected for future space platforms. 36 references.

  17. Durability-Based Design Properties of Reference Crossply Carbon-Fiber Composite

    SciTech Connect

    Corum, J.M.

    2001-04-16

    This report provides recommended durability-based design properties and criteria for a crossply carbon-fiber composite for possible automotive structural applications. Although the composite utilized aerospace-grade carbon-fiber reinforcement, it was made by a rapid-molding process suitable for high-volume automotive use. The material is the first in a planned progression of candidate composites to be characterized as part of an Oak Ridge National Laboratory project entitled Durability of Carbon-Fiber Composites. The overall goal of the project, which is sponsored by the U.S. Department of Energy's Office of Advanced Automotive Technologies and is closely coordinated with the Advanced Composites Consortium, is to develop durability-driven design data and criteria to assure the long-term integrity of carbon-fiber-based composite systems for automotive structural applications. The composite addressed in this report is a ({+-}45{degree})3S crossply consisting of continuous Thornel T300 fibers in a Baydur 420 IMR urethane matrix. This composite is highly anisotropic with two dominant fiber orientations--0/90{degree} and {+-}45{degree}. Properties and models were developed for both orientations. This document is in two parts. Part 1 provides design data and correlations, while Part 2 provides the underlying experimental data and models. The durability issues addressed include the effects of short-time, cyclic, and sustained loadings; temperature; fluid environments; and low-energy impacts (e.g., tool drops and kickups of roadway debris) on deformation, strength, and stiffness. Guidance for design analysis, time-independent and time-dependent allowable stresses, rules for cyclic loadings, and damage-tolerance design guidance are provided.

  18. Managing data for a multicountry longitudinal study: experience from the WHO Multicentre Growth Reference Study.

    PubMed

    Onyango, Adelheid W; Pinol, Alain J; de Onis, Mercedes

    2004-03-01

    The World Health Organization (WHO) Multicentre Growth Reference (MGRS) data management protocol was designed to create and manage a large data bank of information collected from multiple sites over a period of several years. Data collection and processing instruments were prepared centrally and used in a standardized fashion across sites. The data management system contained internal validation features for timely detection of data errors, and its standard operating procedures stipulated a method of master file updating and correction that maintained a clear trail for data auditing purposes. Each site was responsible for collecting, entering, verifying, and validating data, and for creating site-level master files. Data from the sites were sent to the MGRS Coordinating Centre every month for master file consolidation and more extensive quality control checking. All errors identified at the Coordinating Centre were communicated to the site for correction at source. The protocol imposed transparency on the sites' data management activities but also ensured access to technical help with operation and maintenance of the system. Through the rigorous implementation of what has been a highly demanding protocol, the MGRS has accumulated a large body of very high-quality data. PMID:15069919

  19. Advanced Design Studies. Final report

    SciTech Connect

    Steiner, Don

    2012-12-01

    The ARIES-CS project was a multi-year multi-institutional project to assess the feasibility of a compact stellarator as a fusion power plant. The work herein describes efforts to help design one aspect of the device, the divertor, which is responsible for the removal of particle and heat flux from the system, acting as the first point of contact between the magnetically confined hot plasma and the outside world. Specifically, its location and topology are explored, extending previous work on the sub ject. An optimized design is determined for the thermal particle flux using a suite of 3D stellarator design codes which trace magnetic field lines from just inside the confined plasma edge to their strike points on divertor plates. These divertor plates are specified with a newly developed plate design code. It is found that a satisfactory thermal design exists which maintains the plate temperature and heat load distribution below tolerable engineering limits. The design is unique, including a toroidal taper on the outboard plates which was found to be important to our results. The maximum thermal heat flux for the final design was 3.61 M W/m2 and the maximum peaking factor was 10.3, below prescribed limits of 10 M W/m2 and 15.6, respectively. The median length of field lines reaching the plates is about 250 m and their average angle of inclination to the surface is 2 deg. Finally, an analysis of the fast alphas, resulting from fusion in the core, which escape the plasma was performed. A method is developed for obtaining the mapping from magnetic coordinates to real-space coordinates for the ARIES-CS. This allows the alpha exit locations to be identified in real space for the first time. These were then traced using the field line algorithm as well as a guiding center routine accounting for their mass, charge, and specific direction and energy. Results show that the current design is inadequate for accommodating the alpha heat flux, capturing at most 1/3 of lost alphas

  20. Identification of suitable reference genes for gene expression studies of shoulder instability.

    PubMed

    Leal, Mariana Ferreira; Belangero, Paulo Santoro; Cohen, Carina; Figueiredo, Eduardo Antônio; Loyola, Leonor Casilla; Pochini, Alberto Castro; Smith, Marília Cardoso; Andreoli, Carlos Vicente; Belangero, Sintia Iole; Ejnisman, Benno; Cohen, Moises

    2014-01-01

    Shoulder instability is a common shoulder injury, and patients present with plastic deformation of the glenohumeral capsule. Gene expression analysis may be a useful tool for increasing the general understanding of capsule deformation, and reverse-transcription quantitative polymerase chain reaction (RT-qPCR) has become an effective method for such studies. Although RT-qPCR is highly sensitive and specific, it requires the use of suitable reference genes for data normalization to guarantee meaningful and reproducible results. In the present study, we evaluated the suitability of a set of reference genes using samples from the glenohumeral capsules of individuals with and without shoulder instability. We analyzed the expression of six commonly used reference genes (ACTB, B2M, GAPDH, HPRT1, TBP and TFRC) in the antero-inferior, antero-superior and posterior portions of the glenohumeral capsules of cases and controls. The stability of the candidate reference gene expression was determined using four software packages: NormFinder, geNorm, BestKeeper and DataAssist. Overall, HPRT1 was the best single reference gene, and HPRT1 and B2M composed the best pair of reference genes from different analysis groups, including simultaneous analysis of all tissue samples. GenEx software was used to identify the optimal number of reference genes to be used for normalization and demonstrated that the accumulated standard deviation resulting from the use of 2 reference genes was similar to that resulting from the use of 3 or more reference genes. To identify the optimal combination of reference genes, we evaluated the expression of COL1A1. Although the use of different reference gene combinations yielded variable normalized quantities, the relative quantities within sample groups were similar and confirmed that no obvious differences were observed when using 2, 3 or 4 reference genes. Consequently, the use of 2 stable reference genes for normalization, especially HPRT1 and B2M, is a

  1. Validation of endogenous control reference genes for normalizing gene expression studies in endometrial carcinoma.

    PubMed

    Ayakannu, Thangesweran; Taylor, Anthony H; Willets, Jonathon M; Brown, Laurence; Lambert, David G; McDonald, John; Davies, Quentin; Moss, Esther L; Konje, Justin C

    2015-09-01

    Real-time quantitative RT-PCR (qRT-PCR) is a powerful technique used for the relative quantification of target genes, using reference (housekeeping) genes for normalization to ensure the generation of accurate and robust data. A systematic examination of the suitability of endogenous reference genes for gene expression studies in endometrial cancer tissues is absent. The aims of this study were therefore to identify and evaluate from the thirty-two possible reference genes from a TaqMan(®) array panel their suitability as an internal control gene. The mathematical software packages geNorm qBasePLUS identified Pumilio homolog 1 (Drosophila) (PUM1), ubiquitin C (UBC), phosphoglycerate kinase (PGK1), mitochondrial ribosomal protein L19 (MRPL19) and peptidylpropyl isomerase A (cyclophilin A) (PPIA) as the best reference gene combination, whilst NormFinder identified MRPL19 as the best single reference gene, with importin 8 (IPO8) and PPIA being the best combination of two reference genes. BestKeeper ranked MRPL19 as the most stably expressed gene. In addition, the study was validated by examining the relative expression of a test gene, which encodes the cannabinoid receptor 1 (CB1). A significant difference in CB1 mRNA expression between malignant and normal endometrium using MRPL19, PPIA, and IP08 in combination was observed. The use of MRPL19, IPO8 and PPIA was identified as the best reference gene combination for the normalization of gene expression levels in endometrial carcinoma. This study demonstrates that the arbitrary selection of endogenous control reference genes for normalization in qRT-PCR studies of endometrial carcinoma, without validation, risks the production of inaccurate data and should therefore be discouraged. PMID:26124453

  2. Vertical Field of View Reference Point Study for Flight Path Control and Hazard Avoidance

    NASA Technical Reports Server (NTRS)

    Comstock, J. Raymond, Jr.; Rudisill, Marianne; Kramer, Lynda J.; Busquets, Anthony M.

    2002-01-01

    Researchers within the eXternal Visibility System (XVS) element of the High-Speed Research (HSR) program developed and evaluated display concepts that will provide the flight crew of the proposed High-Speed Civil Transport (HSCT) with integrated imagery and symbology to permit path control and hazard avoidance functions while maintaining required situation awareness. The challenge of the XVS program is to develop concepts that would permit a no-nose-droop configuration of an HSCT and expanded low visibility HSCT operational capabilities. This study was one of a series of experiments exploring the 'design space' restrictions for physical placement of an XVS display. The primary experimental issues here was 'conformality' of the forward display vertical position with respect to the side window in simulated flight. 'Conformality' refers to the case such that the horizon and objects appear in the same relative positions when viewed through the forward windows or display and the side windows. This study quantified the effects of visual conformality on pilot flight path control and hazard avoidance performance. Here, conformality related to the positioning and relationship of the artificial horizon line and associated symbology presented on the forward display and the horizon and associated ground, horizon, and sky textures as they would appear in the real view through a window presented in the side window display. No significant performance consequences were found for the non-conformal conditions.

  3. Light weight radioisotope heater unit (LWRHU): a technical description of the reference design

    SciTech Connect

    Tate, R.E.

    1982-01-01

    The Light Weight Radioisotope Heater Unit (LWRHU), a new radioisotope heater unit for use in space missions, is a /sup 238/PuO/sub 2/-fueled unit designed to provide a thermal watt in dispersed locations on a spacecraft. The LWRHU is required to maintain the temperature of a component at a level where the component will function reliably in space. Two major constraints are placed on the unit's design; it must be as light as possible and must provide enough protection to immobilize the plutonium fuel to the maximum extent in all phases of the unit's lifetime. The four components are pelletized fuel, platinum-alloy encapsulation, pyrolytic graphite thermal insulation, and high-technology graphite ablation shell. The LWRHU is a cylinder 32 mm (1.26 in.) high and 26 mm (1.02 in.) in diameter. It weighs slightly less than 40 g(.09 lb).

  4. Schematic designs for penetration seals for a reference repository in bedded salt

    SciTech Connect

    Kelsall, P.C.; Case, J.B.; Meyer, D.; Coons, W.E.

    1982-11-01

    The isolation of radioactive wastes in geologic repositories requires that man-made penetrations such as shafts, tunnels, or boreholes are adequately sealed. This report describes schematic seal designs for a repository in bedded salt referenced to the straitigraphy of southeastern New Mexico. The designs are presented for extensive peer review and will be updated as site-specific conceptual designs when a site for a repository in salt has been selected. The principal material used in the seal system is crushed salt obtained from excavating the repository. It is anticipated that crushed salt will consolidate as the repository rooms creep close to the degree that mechanical and hydrologic properties will eventually match those of undisturbed, intact salt. For southeastern New Mexico salt, analyses indicate that this process will require approximately 1000 years for a seal located at the base of one of the repository shafts (where there is little increase in temperature due to waste emplacement) and approximately 400 years for a seal located in an access tunnel within the repository. Bulkheads composed of contrete or salt bricks are also included in the seal system as components which will have low permeability during the period required for salt consolidation.

  5. Epidemiological study air disaster in Amsterdam (ESADA): study design

    PubMed Central

    Slottje, Pauline; Huizink, Anja C; Twisk, Jos WR; Witteveen, Anke B; van der Ploeg, Henk M; Bramsen, Inge; Smidt, Nynke; Bijlsma, Joost A; Bouter, Lex M; van Mechelen, Willem; Smid, Tjabe

    2005-01-01

    Background In 1992, a cargo aircraft crashed into apartment buildings in Amsterdam, killing 43 victims and destroying 266 apartments. In the aftermath there were speculations about the cause of the crash, potential exposures to hazardous materials due to the disaster and the health consequences. Starting in 2000, the Epidemiological Study Air Disaster in Amsterdam (ESADA) aimed to assess the long-term health effects of occupational exposure to this disaster on professional assistance workers. Methods/Design Epidemiological study among all the exposed professional fire-fighters and police officers who performed disaster-related task(s), and hangar workers who sorted the wreckage of the aircraft, as well as reference groups of their non-exposed colleagues who did not perform any disaster-related tasks. The study took place, on average, 8.5 years after the disaster. Questionnaires were used to assess details on occupational exposure to the disaster. Health measures comprised laboratory assessments in urine, blood and saliva, as well as self-reported current health measures, including health-related quality of life, and various physical and psychological symptoms. Discussion In this paper we describe and discuss the design of the ESADA. The ESADA will provide additional scientific knowledge on the long-term health effects of technological disasters on professional workers. PMID:15921536

  6. Preliminary aerosol generator design studies

    NASA Technical Reports Server (NTRS)

    Stampfer, J. F., Jr.

    1976-01-01

    The design and construction of a prototype vaporization generator for highly dispersed sodium chloride aerosols is described. The aerosol generating system is to be used in the Science Simulator of the Cloud Physics Laboratory Project and as part of the Cloud Physics Laboratory payload to be flown on the shuttle/spacelab.

  7. A channel simulator design study

    NASA Technical Reports Server (NTRS)

    Devito, D. M.; Goutmann, M. M.; Harper, R. C.

    1971-01-01

    A propagation path simulator was designed for the channel between a Tracking and Data Relay Satellite in geostationary orbit and a user spacecraft orbiting the earth at an altitude between 200 and 4000 kilometers. The simulator is required to duplicate the time varying parameters of the propagation channel.

  8. Altair Descent and Ascent Reference Trajectory Design and Initial Dispersion Analyses

    NASA Technical Reports Server (NTRS)

    Kos, Larry D.; Polsgrove, Tara T.; Sostaric, Ronald r.; Braden, Ellen M.; Sullivan, Jacob J.; Lee, Thanh T.

    2010-01-01

    The Altair Lunar Lander is the linchpin in the Constellation Program (CxP) for human return to the Moon. Altair is delivered to low Earth orbit (LEO) by the Ares V heavy lift launch vehicle, and after subsequent docking with Orion in LEO, the Altair/Orion stack is delivered through translunar injection (TLI). The Altair/Orion stack separating from the Earth departure stage (EDS) shortly after TLI and continues the flight to the Moon as a single stack. Altair performs the lunar orbit insertion (LOI) maneuver, targeting a 100-km circular orbit. This orbit will be a polar orbit for missions landing near the lunar South Pole. After spending nearly 24 hours in low lunar orbit (LLO), the lander undocks from Orion and performs a series of small maneuvers to set up for descending to the lunar surface. This descent begins with a small deorbit insertion (DOI) maneuver, putting the lander on an orbit that has a perilune of 15.24 km (50,000 ft), the altitude where the actual powered descent initiation (PDI) commences. At liftoff from Earth, Altair has a mass of 45 metric tons (mt). However after LOI (without Orion attached), the lander mass is slightly less than 33 mt at PDI. The lander currently has a single descent module main engine, with TBD lb(sub f) thrust (TBD N), providing a thrust-to-weight ratio of approximately TBD Earth g's at PDI. LDAC-3 (Lander design and analysis cycle #3) is the most recently closed design sizing and mass properties iteration. Upgrades for loss of crew (LDAC-2) and loss of mission (LDAC-3) have been incorporated into the lander baseline design (and its Master Equipment List). Also, recently, Altair has been working requirements analyses (LRAC-1). All nominal data here are from the LDAC-3 analysis cycle. All dispersions results here are from LRAC-1 analyses.

  9. Human Health and Performance Aspects of Mars Design Reference Mission of July, 1997

    NASA Technical Reports Server (NTRS)

    Charles, John B.

    1999-01-01

    The human element is the most complex element of the mission design Mars missions will pose significant physiological and psychological challenges to crew members Some challenges (human engineering, life support) must be overcome (potential "non-starters") Some challenges (bone, radiation) may be show-stoppers ISS will only Indirectly address Mars questions before any "Go/No Go" decision Significant amount of ground-based and specialized flight research will be required -- Critical Path Roadmap project will direct HSLSPO's research toward Mars exploration objectives

  10. Destination Deimos: A Design Reference Architecture for Initial Human Exploration of the Mars System

    NASA Technical Reports Server (NTRS)

    Logan, James S.; Adamo, D. R.

    2011-01-01

    The two biggest challenges to successful human operations in interplanetary space are flight dynamics, constrained by the cold hard physics of the rocket equation, and bioastronautics, the psychophysiological realities of human adaptation, or lack thereof, to the deep space environment. Without substantial innovation in project/mission architecture and vehicle design, human exploration of the Mars system could be problematic for decades. Although a human landing on Mars is inevitable, humans-in-the-loop telerobotic exploration from the outer Martian moon Deimos is the best way to begin. Precursor robotic missions for reconnaissance and local site preparation will be required.