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Sample records for eurisol design study

  1. Structural-hydraulic test of the liquid metal EURISOL target mock-up

    NASA Astrophysics Data System (ADS)

    Milenković, Rade Ž.; Dementjevs, Sergejs; Samec, Karel; Platacis, Ernests; Zik, Anatolij; Flerov, Aleksej; Manfrin, Enzo; Thomsen, Knud

    2009-08-01

    Structural-hydraulic tests of the European Isotope Separation On-Line (EURISOL) neutron converter target mock-up, named MErcury Target EXperiment 1 (METEX 1), have been conducted by Paul Scherrer Institut (PSI, Switzerland) in cooperation with Institute of Physics of the University of Latvia (IPUL, Latvia). PSI proceeded with extensive thermal-hydraulic and structural computational studies, followed by the target mock-up tests carried out on the mercury loop at IPUL. One of the main goals of the METEX 1 test is to investigate the hydraulic and structural behaviour of the EURISOL target mock-up for various inlet flow conditions (i.e. mass flow rates) and, in particular, for nominal operating flow rate and pressure in the system. The experimental results were analysed by advanced time-frequency methods such as Short-Time Fourier Transform in order to check the vibration characteristics of the mock-up and the resonance risk. The experimental results (obtained in METEX 1), which include inlet flow rate, pressure of the cover gas, total pressure loss, structural acceleration, sound and strain data, were jointly analysed together with numerical data obtained from Computational Fluid Dynamics (CFD).

  2. Prospects for advanced electron cyclotron resonance and electron beam ion source charge breeding methods for EURISOL

    SciTech Connect

    Delahaye, P.; Jardin, P.; Maunoury, L.; Traykov, E.; Varenne, F.; Angot, J.; Lamy, T.; Sortais, P.; Thuillier, T.; Ban, G.; Celona, L.; Lunney, D.; Choinski, J.; Gmaj, P.; Jakubowski, A.; Steckiewicz, O.; Kalvas, T.; and others

    2012-02-15

    As the most ambitious concept of isotope separation on line (ISOL) facility, EURISOL aims at producing unprecedented intensities of post-accelerated radioactive isotopes. Charge breeding, which transforms the charge state of radioactive beams from 1+ to an n+ charge state prior to post-acceleration, is a key technology which has to overcome the following challenges: high charge states for high energies, efficiency, rapidity and purity. On the roadmap to EURISOL, a dedicated R and D is being undertaken to push forward the frontiers of the present state-of-the-art techniques which use either electron cyclotron resonance or electron beam ion sources. We describe here the guidelines of this R and D.

  3. EURISOL Desktop Assistant Toolkit (EDAT): A modeling, simulation and visualization support to the preliminary radiological assessment of RIB projects

    NASA Astrophysics Data System (ADS)

    Vamanu, D.; Vamanu, B.; Acasandrei, V.; Maceika, E.; Plukis, A.

    2010-04-01

    The paper describes an approach taken within the EURISOL-DS project (European Isotope Separation Online Radioactive Ion Beam Facility) to a number of safety and radioprotection issues raised by the advent of radioactive ion beam facilities in the cutting edge area of particle accelerators. The ensuing solution emerged from a collaborative effort of the investigating team-in-charge, affiliated with the Horia Hulubei National Institute of Physics and Nuclear Engineering in Bucharest, with expert colleagues at the Physics Institute in Vilnius, and at CERN, within the participation in the EURISOL-DS project, Sub-Task B: Radiation, Activation, Shielding and Doses of the Safety and Radioprotection, Task 5. The work was primarily geared towards the identification of knowledge and data in line with validated, accepted and nationally/internationally recommended methods and models of radiological assessment applied within the nuclear power fuel cycle, deemed to be suitable for assessing health and environmental impact of accelerator operations as well. As a result, a computer software platform code-named “EURISOL Desktop Assistant Toolkit” was developed. The software is, inter alia, capable to assess radiation doses from pure or isotopically mixed open or shielded point sources; emergency response-relevant doses; critical group doses via complex pathways, including the air, the water, and the food chain and derived release limits for the normal, routine operations of nuclear facilities. Dedicated data libraries and GIS (Geographic Information System) facilities assist the input/output operations.

  4. [Ergonomic technology. Design study].

    PubMed

    Apostol, I; Ciobanu, O

    2007-01-01

    The paper deals with domains and technological developments and related supports that enhance the rehabilitation process. Ergonomic Technology, Rehabilitation Engineering, Accessibility and Assistive technology are factors involved in promoting a greater independence for people with disabilities by designing and developing new devices with improved design and functionality. Results of a device design study for people with disabilities are presented.

  5. Study design: the basics.

    PubMed

    Lim, Hyun Ja; Hoffmann, Raymond G

    2007-01-01

    In biomedical research, meaningful conclusions can only be drawn based on data collected from a valid scientific design using appropriate statistical methods. Therefore, the selection of an appropriate study design is important in order to provide an unbiased and scientific evaluation of the research questions. In this chapter, the different kinds of experimental studies commonly used in biology and medicine are introduced. A brief survey of basic experimental study designs, randomization, blinding, possible biases, issues in data analysis, and interpretation of the study results are mainly provided.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Parametric study of a high current-density EBIS Charge Breeder regarding Two Stream plasma Instability (TSI)

    NASA Astrophysics Data System (ADS)

    Shornikov, Andrey; Mertzig, Robert; Breitenfeldt, Martin; Lombardi, Alessandra; Wenander, Fredrik; Pikin, Alexander

    2016-06-01

    In this paper we report on our results from the design study of an advanced Electron Beam Ion Source (EBIS) based Charge Breeder (ECB). The ECB should fulfill the requirements of the HIE-ISOLDE upgrade, and if possible be adapted for ion injection into TSR@ISOLDE, as well as serve as an early prototype of a future EURISOL ECB. Fulfilling the HIE-ISOLDE/TSR@ISOLDE specifications requires simultaneous increase in electron beam energy, current and current density in order to provide the requested beams with proper charge state, high intensity and with a specified pulse repetition rate. We have carried out a study on the technical requirements of the ECB. The obtained parameters were optimized to comply with technical limitations arising from the electron beam technology and plasma physics in an ECB.

  11. 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.

  12. 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

  13. 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.

  14. Architecture as Design Study.

    ERIC Educational Resources Information Center

    Kauppinen, Heta

    1989-01-01

    Explores the use of analogies in architectural design, the importance of Gestalt theory and aesthetic cannons in understanding and being sensitive to architecture. Emphasizes the variation between public and professional appreciation of architecture. Notes that an understanding of architectural process enables students to improve the aesthetic…

  15. 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.

  16. 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.

  17. Designing verbal autopsy studies

    PubMed Central

    2010-01-01

    Background Verbal autopsy analyses are widely used for estimating cause-specific mortality rates (CSMR) in the vast majority of the world without high-quality medical death registration. Verbal autopsies -- survey interviews with the caretakers of imminent decedents -- stand in for medical examinations or physical autopsies, which are infeasible or culturally prohibited. Methods and Findings We introduce methods, simulations, and interpretations that can improve the design of automated, data-derived estimates of CSMRs, building on a new approach by King and Lu (2008). Our results generate advice for choosing symptom questions and sample sizes that is easier to satisfy than existing practices. For example, most prior effort has been devoted to searching for symptoms with high sensitivity and specificity, which has rarely if ever succeeded with multiple causes of death. In contrast, our approach makes this search irrelevant because it can produce unbiased estimates even with symptoms that have very low sensitivity and specificity. In addition, the new method is optimized for survey questions caretakers can easily answer rather than questions physicians would ask themselves. We also offer an automated method of weeding out biased symptom questions and advice on how to choose the number of causes of death, symptom questions to ask, and observations to collect, among others. Conclusions With the advice offered here, researchers should be able to design verbal autopsy surveys and conduct analyses with greatly reduced statistical biases and research costs. PMID:20573233

  18. 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.

  19. Instructional Designers at Work: A Study of How Designers Design

    ERIC Educational Resources Information Center

    Dicks, Dennis; Ives, Cindy

    2008-01-01

    Instructional design (ID) in its short life has been dominated by behaviourist approaches despite critique focusing on issues of practice as well as theory. Nonetheless, little research has addressed two fundamental questions: "What constitutes good instructional design?" and "How do instructional designers create good design?"…

  20. 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…

  1. 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).

  2. STUDY CARRELS, DESIGNS FOR INDEPENDENT STUDY SPACE.

    ERIC Educational Resources Information Center

    BEYNON, JOHN

    BECAUSE OF THE DEMAND FOR INDIVIDUALIZED INSTRUCTION, NEW SCHOOLS ARE BEING PLANNED WITH LESS CLASSROOM SPACE AND MORE LIBRARY AND INDIVIDUAL STUDY SPACES. THESE NEW SCHOOLS REQUIRE NEW KINDS OF FURNITURE DESIGNED PRIMARILY TO GIVE THE STUDENT A DEGREE OF PRIVACY RATHER THAN TO PROVIDE OPTIMUM CONTROL TO TEACHERS. THE CARREL, PREVIOUSLY USED…

  3. 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.

  4. 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

  5. The proton driver design study

    SciTech Connect

    Editors: W. Chou, C.M. Ankenbrandt and E.I. Malamud

    2001-03-08

    In a 1997 summer study, a team led by Steve Holmes formulated a development plan for the Fermilab proton source and described the results in TM-2021. Subsequently, at the end of 1998, a task group was formed to prepare a detailed design of a high intensity facility called the Proton Driver to replace the Fermilab Booster. In the past two years the design effort has attracted more than fifty participants, mostly from the Beams Division. Physicists and engineers from the Technical Division and FESS as well as other institutions, including the Illinois Institute of Technology (IIT), Stanford University, University of Hawaii, CERN in Switzerland, Rutherford Appleton Laboratory in England and the IHEP in Russia also contributed heavily. The results of that effort are summarized in this document describing the design of a 16 GeV synchrotron, two new beam transport lines (a 400 MeV injection line and a 12/16 GeV extraction line), and related improvements to the present negative ion source and the 400 MeV Linac. A construction cost estimate is presented in Appendix A.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  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. 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)

  13. 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

  14. Advances on ELIC Design Studies

    SciTech Connect

    Bogacz, S. Alex; Bogacz, S.; Chevtsov, P.; Derbenev, Ya.; Evtushenko, P.; Krafft, G.; Hutton, A.; Li, R.; Merminga, L.; Musson, J.; Yunn, B.; Zhang, Y.; Sayed, H.; Qiang, J.

    2008-06-16

    A conceptual design of a ring-ring electron-ion collider based on CEBAF with a center-of-mass energy up to 90 GeV at luminosity up to 1035 cm-2s-1 has been proposed at JLab to fulfil science requirements. Here, we summarize design progress including collider ring and interaction region optics with chromatic aberration compensation. Electron polarization in the Figure-8 ring, stacking of ion beams in an accumulator-cooler ring, beam-beam simulations and a faster kicker for the circulator electron cooler ring are also discussed.

  15. Multimission Aircraft Design Study, Payload

    DTIC Science & Technology

    2003-03-01

    number MC2A Multisensor Command and Control Aircraft MC2A-X Multisensor Command and Control Aircraft Experiment MIDS Multifunctional Information and...reconnaissance (ISR) fleet. The MMA is alternately designated as the Multisensor Command and Control Aircraft (MC2A) as indicated in this text. Figure

  16. Submersible Aircraft Concept Design Study

    DTIC Science & Technology

    2010-08-01

    lead to the tips of the wing stalling before the inboard sections, making the aircraft pitch up and potentially stall. In order to combat this, an...the lift being produced by the wing and so reduce hull draft, albeit at the expense of induced drag from the wing . Naval Surface Warfare Center... delta wing design with some blended wing body characteristics was adopted. This approach gives excellent internal volume characteristics whilst

  17. Critical Studies in Art and Design Education.

    ERIC Educational Resources Information Center

    Thistlewood, David, Ed.

    This book brings together British and U.S. contributions to the debate of a critical studies approach to art and design education. The approach links practice and appreciation. But critical differences exist in definitions of the term design, with the U.S. recognition of design as the use of principles and elements of art in works and a British…

  18. Recycler ring conceptual design study

    SciTech Connect

    Jackson, G.

    1995-07-18

    The Tevatron Collider provides the highest center of mass energy collisions in the world. To fully exploit this unique tool, Fermilab is committed to a program of accelerator upgrades for the purpose of increasing the Collider luminosity. Over the past 7 years the luminosity has been increased from a peak of 1.6{times}10{sup 30}cm{sup {minus}2}sec{sup {minus}1} in 1989 to over 3{times}10{sup 31}cm{sup {minus}2}sec{sup {minus}1} during 1995. The Main Injector will supply a larger flux of protons for antiproton production and more intense proton bunches for use in the Collider, and this is expected to increase the peak luminosity to close to 1{times}10{sup 32}cm{sup {minus}2}sec{sup {minus}1}. Further increases in luminosity will require additional upgrades to the Fermilab accelerator complex. This report documents the design of a new fixed-energy storage ring to be placed in the Main Injector tunnel which will provide an initial factor of 2 increase to 2{times}10{sup 32}cm{sup {minus}2}sec{sup {minus}1}, and ultimately provide the basis for an additional order of magnitude luminosity increase up to 1{times}10{sup 33}cm{sup {minus}2}sec{sup {minus}1}.

  19. Interval Management Display Design Study

    NASA Technical Reports Server (NTRS)

    Baxley, Brian T.; Beyer, Timothy M.; Cooke, Stuart D.; Grant, Karlus A.

    2014-01-01

    In 2012, the Federal Aviation Administration (FAA) estimated that U.S. commercial air carriers moved 736.7 million passengers over 822.3 billion revenue-passenger miles. The FAA also forecasts, in that same report, an average annual increase in passenger traffic of 2.2 percent per year for the next 20 years, which approximates to one-and-a-half times the number of today's aircraft operations and passengers by the year 2033. If airspace capacity and throughput remain unchanged, then flight delays will increase, particularly at those airports already operating near or at capacity. Therefore it is critical to create new and improved technologies, communications, and procedures to be used by air traffic controllers and pilots. National Aeronautics and Space Administration (NASA), the FAA, and the aviation industry are working together to improve the efficiency of the National Airspace System and the cost to operate in it in several ways, one of which is through the creation of the Next Generation Air Transportation System (NextGen). NextGen is intended to provide airspace users with more precise information about traffic, routing, and weather, as well as improve the control mechanisms within the air traffic system. NASA's Air Traffic Management Technology Demonstration-1 (ATD-1) Project is designed to contribute to the goals of NextGen, and accomplishes this by integrating three NASA technologies to enable fuel-efficient arrival operations into high-density airports. The three NASA technologies and procedures combined in the ATD-1 concept are advanced arrival scheduling, controller decision support tools, and aircraft avionics to enable multiple time deconflicted and fuel efficient arrival streams in high-density terminal airspace.

  20. DROPOUT STUDIES, DESIGN AND CONDUCT.

    ERIC Educational Resources Information Center

    SCHRIEBER, DANIEL; AND OTHERS

    ALTHOUGH THE DROPOUT PROBLEM IS ONE OF GREAT CONCERN AT BOTH LOCAL AND NATIONAL LEVELS, IT IS READILY APPARENT THAT THE PROBLEM IS NOT THE SAME EVERYWHERE IN THE COUNTRY. DROPOUT RATES VARY CONSIDERABLY FROM ONE COMMUNITY TO ANOTHER, AND EVEN DIFFER BETWEEN HIGH SCHOOLS IN THE SAME SCHOOL SYSTEM. LIMITATIONS IN PREVIOUS STUDIES OF THE PROBLEM HAVE…

  1. On the Science of Education Design Studies.

    ERIC Educational Resources Information Center

    Shavelson, Richard J.; Phillips, D. C.; Towne, Lisa; Feuer, Michael J.

    2003-01-01

    Asserts that design studies, like all scientific work, must comport with guiding scientific principles and provide adequate warrants for their knowledge claims. Provides a framework that links design study research questions as they evolve over time with corresponding research methods, thus allowing an integration of research methods focused on…

  2. Design study for asteroidal exploitation

    NASA Astrophysics Data System (ADS)

    Adams, Carl; Blissit, Jim; Jarrett, Dave; Sanner, Rob; Yanagawa, Koji

    1985-08-01

    A systematic approach to asteroidal exploitation for the 1990 to 2010 time frame is presented as an initial step toward expanding the use of space beyond the space station by providing a source of lower cost materials. With only a limited amount of information known about the asteroids, reconnaissance and exploration phases to determine the exact locations and compositions of several earth-approaching asteroids are required. Earth-based telescopes are used to locate and study the asteroids, while unmanned probes will return samples of asteroidal material to earth for analysis. After these phases are completed, the retrieval of a 35,000 metric ton piece of the asteroid Anteros is undertaken. A cargo transporter uses magnetoplasmadynamic (MPD) arcjets outbound and a mass-driver using asteroidal material inbound. A crew ship uses ion engines. Low thrust trajectories are used for both spacecraft. A materials processing facility will manufacture propellant pellets and retrieve non-propellant materials for spacecraft use. The cost is 1/10th that to transport the same materials from earth to high earth orbit. The project will cost 25 percent less if done in conjunction with a lunar and Martian base.

  3. ACSYNT inner loop flight control design study

    NASA Technical Reports Server (NTRS)

    Bortins, Richard; Sorensen, John A.

    1993-01-01

    The NASA Ames Research Center developed the Aircraft Synthesis (ACSYNT) computer program to synthesize conceptual future aircraft designs and to evaluate critical performance metrics early in the design process before significant resources are committed and cost decisions made. ACSYNT uses steady-state performance metrics, such as aircraft range, payload, and fuel consumption, and static performance metrics, such as the control authority required for the takeoff rotation and for landing with an engine out, to evaluate conceptual aircraft designs. It can also optimize designs with respect to selected criteria and constraints. Many modern aircraft have stability provided by the flight control system rather than by the airframe. This may allow the aircraft designer to increase combat agility, or decrease trim drag, for increased range and payload. This strategy requires concurrent design of the airframe and the flight control system, making trade-offs of performance and dynamics during the earliest stages of design. ACSYNT presently lacks means to implement flight control system designs but research is being done to add methods for predicting rotational degrees of freedom and control effector performance. A software module to compute and analyze the dynamics of the aircraft and to compute feedback gains and analyze closed loop dynamics is required. The data gained from these analyses can then be fed back to the aircraft design process so that the effects of the flight control system and the airframe on aircraft performance can be included as design metrics. This report presents results of a feasibility study and the initial design work to add an inner loop flight control system (ILFCS) design capability to the stability and control module in ACSYNT. The overall objective is to provide a capability for concurrent design of the aircraft and its flight control system, and enable concept designers to improve performance by exploiting the interrelationships between

  4. Preliminary design study of lunar housing configurations

    NASA Technical Reports Server (NTRS)

    Reynolds, K. H.

    1992-01-01

    A preliminary design study assesses various configurations for habitation of the lunar surface. The study assumes an initial 4-man habitation module expandable to a 48-man concept. Through the numerous coupling combinations of identical modules, five basic configuration types are identified. A design model presents each configuration in light of certain issues. The issues include circulation, internal and external spatial characteristics, functional organizations, and future growth potential. The study discusses the attributes, potentials, and unique requirements of each configuration.

  5. Mirror Advanced Reactor Study interim design report

    SciTech Connect

    Not Available

    1983-04-01

    The status of the design of a tenth-of-a-kind commercial tandem-mirror fusion reactor is described at the midpoint of a two-year study. When completed, the design is to serve as a strategic goal for the mirror fusion program. The main objectives of the Mirror Advanced Reactor Study (MARS) are: (1) to design an attractive tandem-mirror fusion reactor producing electricity and synfuels (in alternate versions), (2) to identify key development and technology needs, and (3) to exploit the potential of fusion for safety, low activation, and simple disposal of radioactive waste. In the first year we have emphasized physics and engineering of the central cell and physics of the end cell. Design optimization and trade studies are continuing, and we expect additional modifications in the end cells to further improve the performance of the final design.

  6. Cost studies for commercial fuselage crown designs

    NASA Technical Reports Server (NTRS)

    Walker, T. H.; Smith, P. J.; Truslove, G.; Willden, K. S.; Metschan, S. L.; Pfahl, C. L.

    1991-01-01

    Studies were conducted to evaluate the cost and weight potential of advanced composite design concepts in the crown region of a commercial transport. Two designs from each of three design families were developed using an integrated design-build team. A range of design concepts and manufacturing processes were included to allow isolation and comparison of cost centers. Detailed manufacturing/assembly plans were developed as the basis for cost estimates. Each of the six designs was found to have advantages over the 1995 aluminum benchmark in cost and weight trade studies. Large quadrant panels and cobonded frames were found to save significant assembly labor costs. Comparisons of high- and intermediate-performance fiber systems were made for skin and stringer applications. Advanced tow placement was found to be an efficient process for skin lay up. Further analysis revealed attractive processes for stringers and frames. Optimized designs were informally developed for each design family, combining the most attractive concepts and processes within that family. A single optimized design was selected as the most promising, and the potential for further optimization was estimated. Technical issues and barriers were identified.

  7. Sequential design approaches for bioequivalence studies with crossover designs.

    PubMed

    Potvin, Diane; DiLiberti, Charles E; Hauck, Walter W; Parr, Alan F; Schuirmann, Donald J; Smith, Robert A

    2008-01-01

    The planning of bioequivalence (BE) studies, as for any clinical trial, requires a priori specification of an effect size for the determination of power and an assumption about the variance. The specified effect size may be overly optimistic, leading to an underpowered study. The assumed variance can be either too small or too large, leading, respectively, to studies that are underpowered or overly large. There has been much work in the clinical trials field on various types of sequential designs that include sample size reestimation after the trial is started, but these have seen only little use in BE studies. The purpose of this work was to validate at least one such method for crossover design BE studies. Specifically, we considered sample size reestimation for a two-stage trial based on the variance estimated from the first stage. We identified two methods based on Pocock's method for group sequential trials that met our requirement for at most negligible increase in type I error rate.

  8. Design optimization studies using COSMIC NASTRAN

    NASA Technical Reports Server (NTRS)

    Pitrof, Stephen M.; Bharatram, G.; Venkayya, Vipperla B.

    1993-01-01

    The purpose of this study is to create, test and document a procedure to integrate mathematical optimization algorithms with COSMIC NASTRAN. This procedure is very important to structural design engineers who wish to capitalize on optimization methods to ensure that their design is optimized for its intended application. The OPTNAST computer program was created to link NASTRAN and design optimization codes into one package. This implementation was tested using two truss structure models and optimizing their designs for minimum weight, subject to multiple loading conditions and displacement and stress constraints. However, the process is generalized so that an engineer could design other types of elements by adding to or modifying some parts of the code.

  9. Design Considerations for Artificial Pancreas Pivotal Studies.

    PubMed

    Russell, Steven J; Beck, Roy W

    2016-07-01

    The development of artificial pancreas systems has evolved to the point that pivotal studies designed to assess efficacy and safety are in progress or soon to be initiated. These pivotal studies are intended to provide the necessary data to gain clearance from the U.S. Food and Drug Administration, coverage by payers, and adoption by patients and clinicians. Although there will not be one design that is appropriate for every system, there are certain aspects of protocol design that will be considerations in all pivotal studies designed to assess efficacy and safety. One key aspect of study design is the intervention to be used by the control group. A case can be made that the control group should use the currently available best technology, which is sensor-augmented pump therapy. However, an equally, if not more, compelling case can be made that the control intervention should be usual care. In this Perspective, we elaborate on this issue and provide a pragmatic approach to the design of clinical trials of artificial pancreas systems.

  10. Engineering study for ISSTRS design concept

    SciTech Connect

    Hertzel, J.S.

    1997-01-31

    Los Alamos Technical Associates, Inc., is pleased to transmit the attached Conceptual Design Package for the Initial Single Shell Tank Retrieval System (ISSTRS), 90% Conceptual Design Review. The package includes the following: (1) ISSTRS Trade Studies: (a) Retrieval Facility Cooling Requirements; (b) Equipment Re-usability between Project W-320 and Tanks 241-C-103 and 241-C-1 05; (c) Sluice Line Options; and (d) Options for the Location of Tanks AX-103 and A-1 02 HVAC Equipment; (2) Drawings; (3) Risk Management Plan; (4) 0850 Interface Control Document; (5) Requirements Traceability Report; and (6) Project Design Specification.

  11. Design Study of Small Efficient Cryocoolers.

    DTIC Science & Technology

    1980-11-01

    I~ V 1k I HL I 1 o’i AL A19 9 0 8 (92 DESIGN STUDY OF SMALL EFFICIENT CRYOCOOLERS PHILIPS LABORATORIES A Division of North American Philips...REPORT A PERIOD COVERED Final Technical Report DESIGN SJDY OF SMALL EFFICIENT CRYOCOOLERS April 14 - Sept. 11, 1980 6. PERFORMING ORG. REPORT NUMBER 7... Stirling cycle refrigerator linear motor cryogenic refrigerator for 100K triple-expansion Stirling -cycle refrigerator free-displacer, free-piston

  12. Cancer genome-sequencing study design.

    PubMed

    Mwenifumbo, Jill C; Marra, Marco A

    2013-05-01

    Discoveries from cancer genome sequencing have the potential to translate into advances in cancer prevention, diagnostics, prognostics, treatment and basic biology. Given the diversity of downstream applications, cancer genome-sequencing studies need to be designed to best fulfil specific aims. Knowledge of second-generation cancer genome-sequencing study design also facilitates assessment of the validity and importance of the rapidly growing number of published studies. In this Review, we focus on the practical application of second-generation sequencing technology (also known as next-generation sequencing) to cancer genomics and discuss how aspects of study design and methodological considerations - such as the size and composition of the discovery cohort - can be tailored to serve specific research aims.

  13. Office Design: A Study of Environment.

    ERIC Educational Resources Information Center

    Manning, Peter, Ed.

    Reporting upon a study of environment which was based on the design of office buildings and office space, the study forms part of a continuing program of environmental research sponsored by Pilkington Brothers Limited of St. Helens, England. In this report the word 'environment' is used in the sense of the sum of the physical and emotional…

  14. Study and design of cryogenic propellant acquisition systems. Volume 1: Design studies

    NASA Technical Reports Server (NTRS)

    Burge, G. W.; Blackmon, J. B.

    1973-01-01

    An in-depth study and selection of practical propellant surface tension acquisition system designs for two specific future cryogenic space vehicles, an advanced cryogenic space shuttle auxiliary propulsion system and an advanced space propulsion module is reported. A supporting laboratory scale experimental program was also conducted to provide design information critical to concept finalization and selection. Designs using localized pressure isolated surface tension screen devices were selected for each application and preliminary designs were generated. Based on these designs, large scale acquisition prototype hardware was designed and fabricated to be compatible with available NASA-MSFC feed system hardware.

  15. Preliminary design study of a baseline MIUS

    NASA Technical Reports Server (NTRS)

    Wolfer, B. M.; Shields, V. E.; Rippey, J. O.; Roberts, H. L.; Wadle, R. C.; Wallin, S. P.; Gill, W. L.; White, E. H.; Monzingo, R.

    1977-01-01

    Results of a conceptual design study to establish a baseline design for a modular integrated utility system (MIUS) are presented. The system concept developed a basis for evaluating possible projects to demonstrate an MIUS. For the baseline study, climate conditions for the Washington, D.C., area were used. The baseline design is for a high density apartment complex of 496 dwelling units with a planned full occupancy of approximately 1200 residents. Environmental considerations and regulations for the MIUS installation are discussed. Detailed cost data for the baseline MIUS are given together with those for design and operating variations under climate conditions typified by Las Vegas, Nevada, Houston, Texas, and Minneapolis, Minnesota. In addition, results of an investigation of size variation effects, for 300 and 1000 unit apartment complexes, are presented. Only conceptual aspects of the design are discussed. Results regarding energy savings and costs are intended only as trend information and for use in relative comparisons. Alternate heating, ventilation, and air conditioning concepts are considered in the appendix.

  16. Deepening Kindergarteners' Science Vocabulary: A Design Study

    ERIC Educational Resources Information Center

    Parsons, Allison Ward; Bryant, Camille Lawrence

    2016-01-01

    Early, effective instruction to introduce both science vocabulary and general academic language may help children build a strong conceptual and linguistic foundation for later instruction. In this study, a design research intervention was employed to expose children to a variety of interrelated science content words to increase both the breadth…

  17. Designing a Futuristic Business Studies Curriculum

    ERIC Educational Resources Information Center

    Mei, Chiew Wye; Siraj, Saedah

    2013-01-01

    This paper is a discourse on the theoretical aspects underpinning the design of the Business Studies curriculum domain. It draws on recent shifts in the business and educational environment of Malaysia, and maps out the methodology and method for expanding and revamping the core ground of the discipline. Using the pragmatic worldview stance, this…

  18. Quiet engine program flight engine design study

    NASA Technical Reports Server (NTRS)

    Klapproth, J. F.; Neitzel, R. E.; Seeley, C. T.

    1974-01-01

    The results are presented of a preliminary flight engine design study based on the Quiet Engine Program high-bypass, low-noise turbofan engines. Engine configurations, weight, noise characteristics, and performance over a range of flight conditions typical of a subsonic transport aircraft were considered. High and low tip speed engines in various acoustically treated nacelle configurations were included.

  19. Overall Rationale and Design of Study.

    ERIC Educational Resources Information Center

    Hegsted, D. Mark

    This paper outlines research designed to establish dietary correlates of malnutrition, and questions the common assumption that high protein foods should be used as dietary supplements in humans. Because thorough investigation of dietary needs in children is ethically unfeasible, squirrel monkeys were used in the research to study the biological…

  20. LST phase A design update study

    NASA Technical Reports Server (NTRS)

    1973-01-01

    An update is presented of the Phase A study of the Large Space Telescope (LST), based on changes in guidelines and new data developed subsequent to the Phase A study. The study defines an LST concept based on the broad mission guidelines provided by the Office of Space Science (OSS), the scientific requirements developed by OSS with the scientific community, and an understanding of long range NASA planning current at the time the study was performed. A low cost design approach was followed. This resulted in the use of standard spacecraft hardware, the provision for maintenance at the black box level, growth potential in systems designs, and sharing of shuttle maintenance flights with other payloads (See N73-18449 through N73-18453)

  1. An empirical study of software design practices

    NASA Technical Reports Server (NTRS)

    Card, David N.; Church, Victor E.; Agresti, William W.

    1986-01-01

    Software engineers have developed a large body of software design theory and folklore, much of which was never validated. The results of an empirical study of software design practices in one specific environment are presented. The practices examined affect module size, module strength, data coupling, descendant span, unreferenced variables, and software reuse. Measures characteristic of these practices were extracted from 887 FORTRAN modules developed for five flight dynamics software projects monitored by the Software Engineering Laboratory (SEL). The relationship of these measures to cost and fault rate was analyzed using a contingency table procedure. The results show that some recommended design practices, despite their intuitive appeal, are ineffective in this environment, whereas others are very effective.

  2. Cryogenic Propellant Management Device: Conceptual Design Study

    NASA Technical Reports Server (NTRS)

    Wollen, Mark; Merino, Fred; Schuster, John; Newton, Christopher

    2010-01-01

    Concepts of Propellant Management Devices (PMDs) were designed for lunar descent stage reaction control system (RCS) and lunar ascent stage (main and RCS propulsion) missions using liquid oxygen (LO2) and liquid methane (LCH4). Study ground rules set a maximum of 19 days from launch to lunar touchdown, and an additional 210 days on the lunar surface before liftoff. Two PMDs were conceptually designed for each of the descent stage RCS propellant tanks, and two designs for each of the ascent stage main propellant tanks. One of the two PMD types is a traditional partial four-screen channel device. The other type is a novel, expanding volume device which uses a stretched, flexing screen. It was found that several unique design features simplified the PMD designs. These features are (1) high propellant tank operating pressures, (2) aluminum tanks for propellant storage, and (3) stringent insulation requirements. Consequently, it was possible to treat LO2 and LCH4 as if they were equivalent to Earth-storable propellants because they would remain substantially subcooled during the lunar mission. In fact, prelaunch procedures are simplified with cryogens, because any trapped vapor will condense once the propellant tanks are pressurized in space.

  3. 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.

  4. Physical design study of the CEPC booster

    NASA Astrophysics Data System (ADS)

    Zhang, Chuang

    2016-09-01

    A physical design study of the Circular Electron-Positron Collider (CEPC) booster is reported. The booster provides 120 GeV electron and positron beams for the CEPC collider with top-up injection. The booster is mounted above the collider in the same tunnel. To save cost, the energy of the linac injector for the booster is chosen as 6 GeV, corresponding to a magnetic field of 30.7 Gs. In this paper, the booster lattice is described and optimization of the cell length is discussed. A novel scheme of bypass near the detector of the collider is designed. The extremely low magnetic field caused by low injection energy is studied, and a new ideal of wiggling bands is proposed to mitigate the low-field problem. Beam transfer and injection from the linac to the booster are considered.

  5. DU-AGG pilot plant design study

    SciTech Connect

    Lessing, P.A.; Gillman, H.

    1996-07-01

    The Idaho National Engineering Laboratory (INEL) is developing new methods to produce high-density aggregate (artificial rock) primarily consisting of depleted uranium oxide. The objective is to develop a low-cost method whereby uranium oxide powder (UO[sub 2], U[sub 3]O[sub ]8, or UO[sub 3]) can be processed to produce high-density aggregate pieces (DU-AGG) having physical properties suitable for disposal in low-level radioactive disposal facilities or for use as a component of high-density concrete used as shielding for radioactive materials. A commercial company, G-M Systems, conducted a design study for a manufacturing pilot plant to process DU-AGG. The results of that study are included and summarized in this report. Also explained are design considerations, equipment capacities, the equipment list, system operation, layout of equipment in the plant, cost estimates, and the proposed plan and schedule.

  6. Study designs in thoracic surgery research

    PubMed Central

    Terzi, Alberto; Bertolaccini, Luca

    2016-01-01

    In this short review, we’ll try to specify the differences between evaluation procedures of groups of data, as they present to researchers. The way and time data are gathered defines the type of study is going to shape. When we observe a cluster of data without deliberately interfering with the process we mean to evaluate, we perform an observational study. Observational studies are the main topic of this issue. Upon the contrary, experimental studies imply the direct action of the observer on the study population in order to define the role of a given exposure. The topic of experimental study design will be covered in another issue of this series. PMID:27747029

  7. Electrostatic camera system functional design study

    NASA Technical Reports Server (NTRS)

    Botticelli, R. A.; Cook, F. J.; Moore, R. F.

    1972-01-01

    A functional design study for an electrostatic camera system for application to planetary missions is presented. The electrostatic camera can produce and store a large number of pictures and provide for transmission of the stored information at arbitrary times after exposure. Preliminary configuration drawings and circuit diagrams for the system are illustrated. The camera system's size, weight, power consumption, and performance are characterized. Tradeoffs between system weight, power, and storage capacity are identified.

  8. Preliminary shuttle structural dynamics modeling design study

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The design and development of a structural dynamics model of the space shuttle are discussed. The model provides for early study of structural dynamics problems, permits evaluation of the accuracy of the structural and hydroelastic analysis methods used on test vehicles, and provides for efficiently evaluating potential cost savings in structural dynamic testing techniques. The discussion is developed around the modes in which major input forces and responses occur and the significant structural details in these modes.

  9. A Numerical Climate Observing Network Design Study

    NASA Technical Reports Server (NTRS)

    Stammer, Detlef

    2003-01-01

    This project was concerned with three related questions of an optimal design of a climate observing system: 1. The spatial sampling characteristics required from an ARGO system. 2. The degree to which surface observations from ARGO can be used to calibrate and test satellite remote sensing observations of sea surface salinity (SSS) as it is anticipated now. 3. The more general design of an climate observing system as it is required in the near future for CLIVAR in the Atlantic. An important question in implementing an observing system is that of the sampling density required to observe climate-related variations in the ocean. For that purpose this project was concerned with the sampling requirements for the ARGO float system, but investigated also other elements of a climate observing system. As part of this project we studied the horizontal and vertical sampling characteristics of a global ARGO system which is required to make it fully complementary to altimeter data with the goal to capture climate related variations on large spatial scales (less thanAttachment: 1000 km). We addressed this question in the framework of a numerical model study in the North Atlantic with an 1/6 horizontal resolution. The advantage of a numerical design study is the knowledge of the full model state. Sampled by a synthetic float array, model results will therefore allow to test and improve existing deployment strategies with the goal to make the system as optimal and cost-efficient as possible. Attachment: "Optimal observations for variational data assimilation".

  10. Microgravity isolation system design: A case study

    NASA Technical Reports Server (NTRS)

    Hampton, R. D.; Knospe, C. R.; Allaire, P. E.; Grodsinsky, C. M.

    1994-01-01

    Many acceleration-sensitive, microgravity science experiments will require active vibration isolation from manned orbiters on which they will be mounted. The isolation problem, especially in the case of a tethered payload, is a complex three-dimensional one that is best suited to modern-control design methods. In this paper, extended H(sub 2) synthesis is used to design an active isolator (i.e., controller) for a realistic single-input-multiple-output (SIMO) microgravity vibration isolation problem. Complex mu-analysis methods are used to analyze the isolation system with respect to sensor, actuator, and umbilical uncertainties. The paper fully discusses the design process employed and the insights gained. This design case study provides a practical approach for isolation problems of greater complexity. Issues addressed include a physically intuitive state-space description of the system, disturbance and noise filters, filters for frequency weighting, and uncertainty models. The controlled system satisfies all the performance specifications and is robust with respect to model uncertainties.

  11. MRF study. Part 2: Antenna design

    NASA Technical Reports Server (NTRS)

    1976-01-01

    An assessment of the practical feasibility of the design and construction of an antenna to meet the requirements of a conceptual radar system is studied. Both the subscale antenna, nominally 5 by 4 meters in dimensions, and the full scale antenna, taken as nominally 18 by 4 meters in size, were considered. The examination of feasibility was from electrical, mechanical, and thermal standpoints. Fundamental, electrical, microwave design questions applying to both the subscale and the full scale antennas were considered in greater detail than questions of mechanical configuration and thermal design. Layouts were made in the development of preliminary configurations, along with a deployment method, for the subscale antenna in conjunction with an antenna cluster for alternate arrangements of the three pallet configuration. Implementation of the array and support structure and attachment of the array to the support and thermal provision was considered. Results show that a microwave design of antennas that incorporate traveling wave arrays can be effected with the beam scanned to 45 degrees in elevation without occurrence of higher order beams.

  12. AFE ion mass spectrometer design study

    NASA Technical Reports Server (NTRS)

    Wright, Willie

    1989-01-01

    This final technical report covers the activities engaged in by the University of Texas at Dallas, Center for Space Sciences in conjunction with the NASA Langley Research Center, Systems Engineering Division in design studies directed towards defining a suitable ion mass spectrometer to determine the plasma parameter around the Aeroassisted Flight Experiment vehicle during passage through the earth's upper atmosphere. Additional studies relate to the use of a Langmuir probe to measure windward ion/electron concentrations and temperatures. Selected instrument inlet subsystems were tested in the NASA Ames Arc-Jet Facility.

  13. Design study of a flexible diaphragm

    SciTech Connect

    Whatley, M E; Morgan, J G

    1982-10-01

    A design study was made to meet the requirements for a diaphragm for a rotary seal at the discharge end of the Consolidated Fuel Reprocessing Program`s prototypic voloxidizer. Using a computer program called NEPSAP, the study examined thickness, outer radius, corrugation wavelength and corrugation amplitude as variables, and established the general effect of each on stiffness and stresses. The result comprises a basis for the selection of diaphragms for similar applications. Limited experimental measurements of stress validate the stress values calculated by NEPSAP.

  14. VXIbus data collection system -- A design study

    SciTech Connect

    Hacker, U.; Richter, B.; Weinert, A.; Arlt, R.; Lewis, W.; Swinhoe, M.

    1995-12-31

    The German support program has sponsored the work to investigate the VXIbus as integration platform for safeguards instrumentation. This paper will cover the analysis of the user requirements for a VXIbus based monitoring system for integrated safeguards -- primarily for reliable unattended in-field collection of large amounts of data. The goal is to develop a suitable system architecture. The design of the system makes use of the VXIbus standard as the selected hardware platform Based upon the requirement analysis and the overriding need for high reliability and robustness, a systematic investigation of different operating system options, as well as development and integration tools will be considered. For the software implementation cycle high and low level programming tools are required. The identification of the constraints for the programming platform and the tool selection will be presented. Both the strategic approach, the rules for analysis and design work as well as the executive components for the support of the implementation and production cycle are given. Here all the conditions for reliable, unattended and integrated safeguards monitoring systems will be addressed. The definition of the basic and advanced design principles are covered. The paper discusses the results of a study on a system produced to demonstrate a high data rate timer/counter application.

  15. Advanced Subsonic Airplane Design and Economic Studies

    NASA Technical Reports Server (NTRS)

    Liebeck, Robert H.; Andrastek, Donald A.; Chau, Johnny; Girvin, Raquel; Lyon, Roger; Rawdon, Blaine K.; Scott, Paul W.; Wright, Robert A.

    1995-01-01

    A study was made to examine the effect of advanced technology engines on the performance of subsonic airplanes and provide a vision of the potential which these advanced engines offered. The year 2005 was selected as the entry-into-service (EIS) date for engine/airframe combination. A set of four airplane classes (passenger and design range combinations) that were envisioned to span the needs for the 2005 EIS period were defined. The airframes for all classes were designed and sized using 2005 EIS advanced technology. Two airplanes were designed and sized for each class: one using current technology (1995) engines to provide a baseline, and one using advanced technology (2005) engines. The resulting engine/airframe combinations were compared and evaluated on the basis on sensitivity to basic engine performance parameters (e.g. SFC and engine weight) as well as DOC+I. The advanced technology engines provided significant reductions in fuel burn, weight, and wing area. Average values were as follows: reduction in fuel burn = 18%, reduction in wing area = 7%, and reduction in TOGW = 9%. Average DOC+I reduction was 3.5% using the pricing model based on payload-range index and 5% using the pricing model based on airframe weight. Noise and emissions were not considered.

  16. 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.

  17. Protecting count queries in study design

    PubMed Central

    Sarwate, Anand D; Boxwala, Aziz A

    2012-01-01

    Objective Today's clinical research institutions provide tools for researchers to query their data warehouses for counts of patients. To protect patient privacy, counts are perturbed before reporting; this compromises their utility for increased privacy. The goal of this study is to extend current query answer systems to guarantee a quantifiable level of privacy and allow users to tailor perturbations to maximize the usefulness according to their needs. Methods A perturbation mechanism was designed in which users are given options with respect to scale and direction of the perturbation. The mechanism translates the true count, user preferences, and a privacy level within administrator-specified bounds into a probability distribution from which the perturbed count is drawn. Results Users can significantly impact the scale and direction of the count perturbation and can receive more accurate final cohort estimates. Strong and semantically meaningful differential privacy is guaranteed, providing for a unified privacy accounting system that can support role-based trust levels. This study provides an open source web-enabled tool to investigate visually and numerically the interaction between system parameters, including required privacy level and user preference settings. Conclusions Quantifying privacy allows system administrators to provide users with a privacy budget and to monitor its expenditure, enabling users to control the inevitable loss of utility. While current measures of privacy are conservative, this system can take advantage of future advances in privacy measurement. The system provides new ways of trading off privacy and utility that are not provided in current study design systems. PMID:22511018

  18. Design Study: Rocket Based MHD Generator

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This report addresses the technical feasibility and design of a rocket based MHD generator using a sub-scale LOx/RP rocket motor. The design study was constrained by assuming the generator must function within the performance and structural limits of an existing magnet and by assuming realistic limits on (1) the axial electric field, (2) the Hall parameter, (3) current density, and (4) heat flux (given the criteria of heat sink operation). The major results of the work are summarized as follows: (1) A Faraday type of generator with rectangular cross section is designed to operate with a combustor pressure of 300 psi. Based on a magnetic field strength of 1.5 Tesla, the electrical power output from this generator is estimated to be 54.2 KW with potassium seed (weight fraction 3.74%) and 92 KW with cesium seed (weight fraction 9.66%). The former corresponds to a enthalpy extraction ratio of 2.36% while that for the latter is 4.16%; (2) A conceptual design of the Faraday MHD channel is proposed, based on a maximum operating time of 10 to 15 seconds. This concept utilizes a phenolic back wall for inserting the electrodes and inter-electrode insulators. Copper electrode and aluminum oxide insulator are suggested for this channel; and (3) A testing configuration for the sub-scale rocket based MHD system is proposed. An estimate of performance of an ideal rocket based MHD accelerator is performed. With a current density constraint of 5 Amps/cm(exp 2) and a conductivity of 30 Siemens/m, the push power density can be 250, 431, and 750 MW/m(sup 3) when the induced voltage uB have values of 5, 10, and 15 KV/m, respectively.

  19. Single Mode Optical Waveguide Design Study.

    DTIC Science & Technology

    1981-11-23

    AD-I7g62 CORNING GLASS WORKS NY FIG 20/6 ADA0 21 SINGLE MODE OPTICAL WAVEGUIDE DESIGN STUDY.(U) NOV 81 V A BHAGAVATJLA. D B KECK, R A WESTWIG N00173...Ralph A. Westwig Corning Glass Works ’ 1 / Research and Development-Division Sullivan Park Corning, New York Th document ha bern c -yro vd Spubc rlea...Authors: Venkata A. Bhagavatula Donald B. Keck Ralph A. Westwig Corning Glass Works Research and Development Division Sullivan Park Corning, New York 11

  20. SP-100 radiator design trade study

    NASA Technical Reports Server (NTRS)

    Ewell, Richard

    1992-01-01

    A design trade study of the SP-100 heat rejection subsystem (HRSS) was made. A system code was used to evaluate the sensitivity of the HRSS mass and performance to changes. Variations in heat pipe diameter and cross-section, fin length and thickness, armor thickness, and overall configuration and materials were evaluated. The analysis indicates that the minimum system mass occurs for the case with many small diameter heat pipes, with ducting that maximizes the fraction of the heat pipe evaporator perimeter in contact with it.

  1. Advanced heat receiver conceptual design study

    NASA Technical Reports Server (NTRS)

    Kesseli, James; Saunders, Roger; Batchelder, Gary

    1988-01-01

    Solar Dynamic space power systems are candidate electrical power generating systems for future NASA missions. One of the key components of the solar dynamic power system is the solar receiver/thermal energy storage (TES) subsystem. Receiver development was conducted by NASA in the late 1960's and since then a very limited amount of work has been done in this area. Consequently the state of the art (SOA) receivers designed for the IOC space station are large and massive. The objective of the Advanced Heat Receiver Conceptual Design Study is to conceive and analyze advanced high temperature solar dynamic Brayton and Stirling receivers. The goal is to generate innovative receiver concepts that are half of the mass, smaller, and more efficient than the SOA. It is also necessary that these innovative receivers offer ease of manufacturing, less structural complexity and fewer thermal stress problems. Advanced Brayton and Stirling receiver storage units are proposed and analyzed in this study which can potentially meet these goals.

  2. Genetic Epidemiology of COPD (COPDGene) Study Design

    PubMed Central

    Regan, Elizabeth A.; Hokanson, John E.; Murphy, James R.; Make, Barry; Lynch, David A.; Beaty, Terri H.; Curran-Everett, Douglas; Silverman, Edwin K.; Crapo, James D.

    2010-01-01

    Background COPDGeneis a multicenter observational study designed to identify genetic factors associated with COPD. It will also characterize chest CT phenotypes in COPD subjects, including assessment of emphysema, gas trapping, and airway wall thickening. Finally, subtypes of COPD based on these phenotypes will be used in a comprehensive genome-wide study to identify COPD susceptibility genes. Methods/Results COPDGene will enroll 10,000 smokers with and without COPD across the GOLD stages. Both Non-Hispanic white and African-American subjects are included in the cohort. Inspiratory and expiratory chest CT scans will be obtained on all participants. In addition to the cross-sectional enrollment process, these subjects will be followed regularly for longitudinal studies. A genome-wide association study (GWAS) will be done on an initial group of 4000 subjects to identify genetic variants associated with case-control status and several quantitative phenotypes related to COPD. The initial findings will be verified in an additional 2000 COPD cases and 2000 smoking control subjects, and further validation association studies will be carried out. Conclusions COPDGene will provide important new information about genetic factors in COPD, and will characterize the disease process using high resolution CT scans. Understanding genetic factors and CT phenotypes that define COPD will potentially permit earlier diagnosis of this disease and may lead to the development of treatments to modify progression. PMID:20214461

  3. Feasibility study of an Integrated Program for Aerospace vehicle Design (IPAD). Volume 2: The design process

    NASA Technical Reports Server (NTRS)

    Gillette, W. B.; Turner, M. J.; Southall, J. W.; Whitener, P. C.; Kowalik, J. S.

    1973-01-01

    The extent to which IPAD is to support the design process is identified. Case studies of representative aerospace products were developed as models to characterize the design process and to provide design requirements for the IPAD computing system.

  4. Inertial Motion Capture Costume Design Study.

    PubMed

    Szczęsna, Agnieszka; Skurowski, Przemysław; Lach, Ewa; Pruszowski, Przemysław; Pęszor, Damian; Paszkuta, Marcin; Słupik, Janusz; Lebek, Kamil; Janiak, Mateusz; Polański, Andrzej; Wojciechowski, Konrad

    2017-03-17

    The paper describes a scalable, wearable multi-sensor system for motion capture based on inertial measurement units (IMUs). Such a unit is composed of accelerometer, gyroscope and magnetometer. The final quality of an obtained motion arises from all the individual parts of the described system. The proposed system is a sequence of the following stages: sensor data acquisition, sensor orientation estimation, system calibration, pose estimation and data visualisation. The construction of the system's architecture with the dataflow programming paradigm makes it easy to add, remove and replace the data processing steps. The modular architecture of the system allows an effortless introduction of a new sensor orientation estimation algorithms. The original contribution of the paper is the design study of the individual components used in the motion capture system. The two key steps of the system design are explored in this paper: the evaluation of sensors and algorithms for the orientation estimation. The three chosen algorithms have been implemented and investigated as part of the experiment. Due to the fact that the selection of the sensor has a significant impact on the final result, the sensor evaluation process is also explained and tested. The experimental results confirmed that the choice of sensor and orientation estimation algorithm affect the quality of the final results.

  5. Advanced EVA system design requirements study

    NASA Technical Reports Server (NTRS)

    Woods, T. G.

    1988-01-01

    The results are presented of a study to identify specific criteria regarding space station extravehicular activity system (EVAS) hardware requirements. Key EVA design issues include maintainability, technology readiness, LSS volume vs. EVA time available, suit pressure/cabin pressure relationship and productivity effects, crew autonomy, integration of EVA as a program resource, and standardization of task interfaces. A variety of DOD EVA systems issues were taken into consideration. Recommendations include: (1) crew limitations, not hardware limitations; (2) capability to perform all of 15 generic missions; (3) 90 days on-orbit maintainability with 50 percent duty cycle as minimum; and (4) use by payload sponsors of JSC document 10615A plus a Generic Tool Kit and Specialized Tool Kit description. EVA baseline design requirements and criteria, including requirements of various subsystems, are outlined. Space station/EVA system interface requirements and EVA accommodations are discussed in the areas of atmosphere composition and pressure, communications, data management, logistics, safe haven, SS exterior and interior requirements, and SS airlock.

  6. Inertial Motion Capture Costume Design Study

    PubMed Central

    Szczęsna, Agnieszka; Skurowski, Przemysław; Lach, Ewa; Pruszowski, Przemysław; Pęszor, Damian; Paszkuta, Marcin; Słupik, Janusz; Lebek, Kamil; Janiak, Mateusz; Polański, Andrzej; Wojciechowski, Konrad

    2017-01-01

    The paper describes a scalable, wearable multi-sensor system for motion capture based on inertial measurement units (IMUs). Such a unit is composed of accelerometer, gyroscope and magnetometer. The final quality of an obtained motion arises from all the individual parts of the described system. The proposed system is a sequence of the following stages: sensor data acquisition, sensor orientation estimation, system calibration, pose estimation and data visualisation. The construction of the system’s architecture with the dataflow programming paradigm makes it easy to add, remove and replace the data processing steps. The modular architecture of the system allows an effortless introduction of a new sensor orientation estimation algorithms. The original contribution of the paper is the design study of the individual components used in the motion capture system. The two key steps of the system design are explored in this paper: the evaluation of sensors and algorithms for the orientation estimation. The three chosen algorithms have been implemented and investigated as part of the experiment. Due to the fact that the selection of the sensor has a significant impact on the final result, the sensor evaluation process is also explained and tested. The experimental results confirmed that the choice of sensor and orientation estimation algorithm affect the quality of the final results. PMID:28304337

  7. Design study of prestressed rotor spar concept

    NASA Technical Reports Server (NTRS)

    Gleich, D.

    1980-01-01

    Studies on the Bell Helicopter 540 Rotor System of the AH-1G helicopter were performed. The stiffness, mass and geometric configurations of the Bell blade were matched to give a dynamically similar prestressed composite blade. A multi-tube, prestressed composite spar blade configuration was designed for superior ballistic survivability at low life cycle cost. The composite spar prestresses, imparted during fabrication, are chosen to maintain compression in the high strength cryogenically stretchformed 304-L stainless steel liner and tension in the overwrapped HTS graphite fibers under operating loads. This prestressing results in greatly improved crack propagation and fatigue resistance as well as enhanced fiber stiffness properties. Advantages projected for the prestressed composite rotor spar concept include increased operational life and improved ballistic survivability at low life cycle cost.

  8. Preliminary systems design study assessment report

    SciTech Connect

    Mayberry, J.L.; Feizollahi, F.; Del Signore, J.C.

    1991-10-01

    The System Design Study (SDS), part of the Waste Technology Development Department of the Idaho National Engineering Laboratory (INEL), examined techniques available for the remediation of hazardous and transuranic waste stored at the Radioactive Waste Management Complex's Subsurface Disposal Area at the INEL. Using specific technologies, system concepts for treating the buried waste and the surrounding contaminated soil were evaluated. Evaluation included implementability, effectiveness, and cost. The SDS resulted in the development of technology requirements including demonstration, testing, and evaluation activities needed for implementing each concept. The SDS results are published in eight volumes. Volume I contains an executive summary. The SDS summary and analysis of results are presented in Volume II. Volumes III through VII contain descriptions of twelve system and four subsystem concepts. Volume VIII contains the appendixes.

  9. Preliminary Systems Design Study assessment report

    SciTech Connect

    Mayberry, J.L.; Quapp, W.J.; Feizollahi, F.; Del Signore, J.C.

    1991-07-01

    The System Design Study (SDS), part of the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examined techniques available for the remediation of hazardous and transuranic waste stored at the Radioactive Waste Management Complex's Subsurface Disposal Area at the INEL. Using specific technologies, system concepts for treating the buried waste and the surrounding contaminated soil were evaluated. Evaluation included implementability, effectiveness, and cost. SDS resulted in the development of technology requirements including demonstration, testing, and evaluation activities needed for implementing each concept. The SDS results are published in eight volumes. Volume 1 contains an executive summary. The SDS summary and analysis of results are presented in Volume 2. Volumes 3 through 7 contain detailed descriptions of twelve system and four subsystem concepts. Volume 8 contains the appendixes. 23 refs., 23 figs., 16 tabs.

  10. The microwave radiometer spacecraft: A design study

    NASA Technical Reports Server (NTRS)

    Wright, R. L. (Editor)

    1981-01-01

    A large passive microwave radiometer spacecraft with near all weather capability of monitoring soil moisture for global crop forecasting was designed. The design, emphasizing large space structures technology, characterized the mission hardware at the conceptual level in sufficient detail to identify enabling and pacing technologies. Mission and spacecraft requirements, design and structural concepts, electromagnetic concepts, and control concepts are addressed.

  11. Made to Measure: Designs Tailored to Your Study Needs.

    PubMed

    Jupiter, Daniel C

    2015-01-01

    What is the best study design? Why would we prefer one to another? With many different designs, what should we be looking for in our critical reading of the literature? We discuss a variety of designs, and their appropriate use.

  12. Chicago Healthy Aging Study: Objectives and Design

    PubMed Central

    Pirzada, Amber; Reid, Kathryn; Kim, Daniel; Garside, Daniel B.; Lu, Brandon; Vu, Thanh-Huyen T.; Lloyd-Jones, Donald M.; Zee, Phyllis; Liu, Kiang; Stamler, Jeremiah; Daviglus, Martha L.

    2013-01-01

    Investigators in the Chicago Healthy Aging Study (CHAS) reexamined 1,395 surviving participants aged 65–84 years (28% women) from the Chicago Heart Association Detection Project in Industry (CHA) 1967–1973 cohort whose cardiovascular disease (CVD) risk profiles were originally ascertained at ages 25–44 years. CHAS investigators reexamined 421 participants who were low-risk (LR) at baseline and 974 participants who were non-LR at baseline. LR was defined as having favorable levels of 4 major CVD risk factors: serum total cholesterol level <200 mg/dL and no use of cholesterol-lowering medication; blood pressure 120/≤80 mm Hg and no use of antihypertensive medication; no current smoking; and no history of diabetes or heart attack. While the potential of LR status in overcoming the CVD epidemic is being recognized, the long-term association of LR with objectively measured health in older age has not been examined. It is hypothesized that persons who were LR in 1967–1973 and have survived to older age will have less clinical and subclinical CVD, lower levels of inflammatory markers, and better physical performance/functioning and sleep quality. Here we describe the rationale, objectives, design, and implementation of this longitudinal epidemiologic study, compare baseline and follow-up characteristics of participants and nonparticipants, and highlight the feasibility of reexamining study participants after an extended period postbaseline with minimal interim contact. PMID:23669655

  13. HEALTHY study rationale, design and methods

    PubMed Central

    2009-01-01

    The HEALTHY primary prevention trial was designed and implemented in response to the growing numbers of children and adolescents being diagnosed with type 2 diabetes. The objective was to moderate risk factors for type 2 diabetes. Modifiable risk factors measured were indicators of adiposity and glycemic dysregulation: body mass index ≥85th percentile, fasting glucose ≥5.55 mmol l-1 (100 mg per 100 ml) and fasting insulin ≥180 pmol l-1 (30 μU ml-1). A series of pilot studies established the feasibility of performing data collection procedures and tested the development of an intervention consisting of four integrated components: (1) changes in the quantity and nutritional quality of food and beverage offerings throughout the total school food environment; (2) physical education class lesson plans and accompanying equipment to increase both participation and number of minutes spent in moderate-to-vigorous physical activity; (3) brief classroom activities and family outreach vehicles to increase knowledge, enhance decision-making skills and support and reinforce youth in accomplishing goals; and (4) communications and social marketing strategies to enhance and promote changes through messages, images, events and activities. Expert study staff provided training, assistance, materials and guidance for school faculty and staff to implement the intervention components. A cohort of students were enrolled in sixth grade and followed to end of eighth grade. They attended a health screening data collection at baseline and end of study that involved measurement of height, weight, blood pressure, waist circumference and a fasting blood draw. Height and weight were also collected at the end of the seventh grade. The study was conducted in 42 middle schools, six at each of seven locations across the country, with 21 schools randomized to receive the intervention and 21 to act as controls (data collection activities only). Middle school was the unit of sample size and

  14. Improving study design for antidepressant effectiveness assessment.

    PubMed

    Naudet, Florian; Millet, Bruno; Reymann, Jean Michel; Falissard, Bruno

    2013-09-01

    Antidepressants effectiveness in major depressive disorder (MDD) is still questioned because the extrapolation of randomized controlled trial (RCT) results to "real life" settings is problematic. The application of the RCT paradigm in a disorder of this type, where global care plays a central role, raises questions regarding the internal and external validity of this type of study. Outcome measurement, attrition rates, the ability of the double-blind design to control for expectations, placebo response, the representativeness of trial participants and publication bias are major methodological pitfalls. This review discusses these issues. It is illustrated using original data and proposes some alternatives for assessing antidepressant effectiveness via different approaches. Some are easy to implement, such as ecological measures, qualitative approaches, improvement of analytical strategy and improvement of blinding procedures. Some are sophisticated, involving temporary deception to deal with the confounding effect of expectations, and they raise ethical issues. Others resort to external validity, this being the case in observational studies. But all are necessary to explore antidepressant effectiveness.

  15. Instructional Design: Case Studies in Communities of Practice

    ERIC Educational Resources Information Center

    Keppell, Michael, Ed.

    2007-01-01

    "Instructional Design: Case Studies in Communities of Practice" documents real-world experiences of instructional designers and staff developers who work in communities of practice. "Instructional Design: Case Studies in Communities of Practice" explains the strategies and heuristics used by instructional designers when working…

  16. Design study of the storage ring EUTERPE

    NASA Astrophysics Data System (ADS)

    Xi, Boling; Botman, J. I. M.; Timmermans, C. J.; Hagedoorn, H. L.

    1992-05-01

    At present the 400 MeV electron storage ring EUTERPE is being constructed at the Eindhoven University of Technology. It is a university project set up for studies of charged particle beam dynamics and applications of synchroton radiation, and for the education of students in these fields. The design of the ring is described in this paper. Considering the requirements of users in different fields, a lattice based on a so-called triple bend achromat structure with a high flexibility has been chosen. With this lattice, different optical options, including the HBSB (high brightness, small beam), the SBL (short bunch length) and the HLF (high light flux) modes can be realized. A small emittance of 7 nm rad and a short bunch length of the order of several mm can be achieved. In the first phase the synchrotron radiation in the UV and XUV region (the critical wavelength is 8.3 nm) will be provided from the regular dipole magnets. Later on, a 10 T wiggler magnet and other special inserters will be added, and other applications and beam dynamics studies will be feasible. Bending magnets are of the parallel faced C configuration. The effective aperture of the vacuum chamber is 2.3 cm (vertical) in the bending magnets and 4.7 cm elsewhere with a working vacuum condition of 10-9 Torr. Collective effects have been studied initially. First calculations indicate that a lifetime of several hours, influenced by the Touschek effect and residual gas scattering will be achievable for a 200 mA beam in the HLF mode for the standard rf parameters. A 70 MeV racetrack microtron will serve as injector for the ring.

  17. Pharmacokinetic Studies in Infants Using Minimal-risk Study Designs

    PubMed Central

    Autmizguine, J; Benjamin, DK; Smith, PB; Sampson, M; Ovetchkine, P; Cohen-Wolkowiez, M.; Watt, KM

    2015-01-01

    Infants are therapeutic orphans. Many drugs used in infants are used “off-label”, increasing the risk of drug toxicity and suboptimal efficacy in this vulnerable population. This knowledge gap in clinical pharmacology is partly attributed to challenges associated with conducting clinical trials in infants. Consequently, there is a need for novel and efficient study designs more suited to this population. Available literature describing the use of minimal-risk approaches to characterize the pharmacokinetics (PK) of drugs in infants was critically reviewed. Population PK approach with sparse sampling was found to be well established. Other, more recent alternatives, like dried blood spots sampling, opportunistic design, and the use of non-blood matrices are promising strategies with an increasing number of applications in infants. Physiologically based pharmacokinetic modeling provides valuable insight in drug disposition but still needs more prospective validation. Increasing experience with these methods provides understanding of their strengths and limitations and will help improve the design of future PK studies in infants. PMID:24844642

  18. A Case Study in CAD Design Automation

    ERIC Educational Resources Information Center

    Lowe, Andrew G.; Hartman, Nathan W.

    2011-01-01

    Computer-aided design (CAD) software and other product life-cycle management (PLM) tools have become ubiquitous in industry during the past 20 years. Over this time they have continuously evolved, becoming programs with enormous capabilities, but the companies that use them have not evolved their design practices at the same rate. Due to the…

  19. New Study Designs | Division of Cancer Prevention

    Cancer.gov

    The Division of Cancer Prevention is expanding clinical research beyond standard trial designs to find interventions that may play a role in more than one prevalent disease. | The Division of Cancer Prevention is expanding clinical research beyond standard trial designs to find interventions that may play a role in more than one prevalent disease.

  20. Software design studies emphasizing Project LOGOS

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The results of a research project on the development of computer software are presented. Research funds of $200,000 were expended over a three year period for software design and projects in connection with Project LOGOS (computer-aided design and certification of computing systems). Abstracts of theses prepared during the project are provided.

  1. Low vision goggles: optical design studies

    NASA Astrophysics Data System (ADS)

    Levy, Ofer; Apter, Boris; Efron, Uzi

    2006-08-01

    Low Vision (LV) due to Age Related Macular Degeneration (AMD), Glaucoma or Retinitis Pigmentosa (RP) is a growing problem, which will affect more than 15 million people in the U.S alone in 2010. Low Vision Aid Goggles (LVG) have been under development at Ben-Gurion University and the Holon Institute of Technology. The device is based on a unique Image Transceiver Device (ITD), combining both functions of imaging and Display in a single chip. Using the ITD-based goggles, specifically designed for the visually impaired, our aim is to develop a head-mounted device that will allow the capture of the ambient scenery, perform the necessary image enhancement and processing, and re-direct it to the healthy part of the patient's retina. This design methodology will allow the Goggles to be mobile, multi-task and environmental-adaptive. In this paper we present the optical design considerations of the Goggles, including a preliminary performance analysis. Common vision deficiencies of LV patients are usually divided into two main categories: peripheral vision loss (PVL) and central vision loss (CVL), each requiring different Goggles design. A set of design principles had been defined for each category. Four main optical designs are presented and compared according to the design principles. Each of the designs is presented in two main optical configurations: See-through system and Video imaging system. The use of a full-color ITD-Based Goggles is also discussed.

  2. 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.

  3. Argonne Tau-charm factory collider design study

    SciTech Connect

    Teng, L.C.; Crosbie, E.A.; Norem, J.

    1995-12-01

    The design approach and design principles for a Tau-charm Factory at Argonne were studied. These studies led to a set of preliminary parameters and tentative component features as presented in this paper.

  4. PLUTONIUM-238 PRODUCTION TARGET DESIGN STUDIES

    SciTech Connect

    Hurt, Christopher J; Wham, Robert M; Hobbs, Randall W; Owens, R Steven; Chandler, David; Freels, James D; Maldonado, G Ivan

    2014-01-01

    A new supply chain is planned for plutonium-238 using existing reactors at the Oak Ridge National Laboratory (ORNL) and Idaho National Laboratory (INL) and existing chemical recovery facilities at ORNL. Validation and testing activities for new irradiation target designs have been conducted in three phases over a 2 year period to provide data for scale-up to production. Target design, qualification, target fabrication, and irradiation of fully-loaded targets have been accomplished. Data from post-irradiation examination (PIE) supports safety analysis and irradiation of future target designs.

  5. A study of commuter airplane design optimization

    NASA Technical Reports Server (NTRS)

    Keppel, B. V.; Eysink, H.; Hammer, J.; Hawley, K.; Meredith, P.; Roskam, J.

    1978-01-01

    The usability of the general aviation synthesis program (GASP) was enhanced by the development of separate computer subroutines which can be added as a package to this assembly of computerized design methods or used as a separate subroutine program to compute the dynamic longitudinal, lateral-directional stability characteristics for a given airplane. Currently available analysis methods were evaluated to ascertain those most appropriate for the design functions which the GASP computerized design program performs. Methods for providing proper constraint and/or analysis functions for GASP were developed as well as the appropriate subroutines.

  6. Empirical studies of software design: Implications for SSEs

    NASA Technical Reports Server (NTRS)

    Krasner, Herb

    1988-01-01

    Implications for Software Engineering Environments (SEEs) are presented in viewgraph format for characteristics of projects studied; significant problems and crucial problem areas in software design for large systems; layered behavioral model of software processes; implications of field study results; software project as an ecological system; results of the LIFT study; information model of design exploration; software design strategies; results of the team design study; and a list of publications.

  7. Mars orbiter conceptual systems design study

    NASA Technical Reports Server (NTRS)

    Dixon, W.; Vogl, J.

    1982-01-01

    Spacecraft system and subsystem designs at the conceptual level to perform either of two Mars Orbiter missions, a Climatology Mission and an Aeronomy Mission were developed. The objectives of these missions are to obtain and return data.

  8. 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

  9. Computational Studies and Designs for Fast Ignition

    NASA Astrophysics Data System (ADS)

    Nagatomo, H.; Johzaki, T.; Nakamura, T.; Sakagami, H.; Mima, K.

    2006-12-01

    The fast ignition scheme is one of the most fascinating and feasible ignition schemes for the inertial fusion energy. At ILE Osaka University, FIREX (Fast Ignition Realization Experiment) project is in progress. Implosion experiments of the cryogenic target are scheduled in near future. There are two key issues for the fast ignition. One is controlling the implosion dynamics to form high density core plasma in non-spherical implosion, and the other is heating the core plasma efficiently by the short pulse high intense laser. The time and space scale in the fast ignition scheme vary widely from initial laser irradiation to solid target, to relativistic laser plasma interaction and final fusion burning. The numerical simulation plays an important role in demonstrating the performance of the fast ignition, designing the targets, and optimizing laser pulse shapes for the scheme. These all the physics are desired to be self-consistently described. In order to study these physics of FI, we have developed "Fast Ignition Integrated Interconnecting code" (FI3), which consists of collective Particle-in-Cell (PIC) code (FISCOF1D/2D), Relativistic Fokker-Planck with hydro code (FIBMET), and 2-dimensional Arbitrary-Lagrangian-Eulerian (ALE) radiation hydrodynamics code (PINOCO). Those codes are sophisticated in each suitable plasma parameters, and boundaries conditions and initial conditions for them are imported/exported to each other by way of DCCP, a simple and compact communication tool which enable these codes to communicate each others under executing different machines. We show the feature of the FI3 code, and numerical results of whole process of fast ignition. Individual important physics behind the FI are explained with the numerical results also.

  10. Empirical studies of design software: Implications for software engineering environments

    NASA Technical Reports Server (NTRS)

    Krasner, Herb

    1988-01-01

    The empirical studies team of MCC's Design Process Group conducted three studies in 1986-87 in order to gather data on professionals designing software systems in a range of situations. The first study (the Lift Experiment) used thinking aloud protocols in a controlled laboratory setting to study the cognitive processes of individual designers. The second study (the Object Server Project) involved the observation, videotaping, and data collection of a design team of a medium-sized development project over several months in order to study team dynamics. The third study (the Field Study) involved interviews with the personnel from 19 large development projects in the MCC shareholders in order to study how the process of design is affected by organizationl and project behavior. The focus of this report will be on key observations of design process (at several levels) and their implications for the design of environments.

  11. The Study of the Relationship between Probabilistic Design and Axiomatic Design Methodology. Volume 1

    NASA Technical Reports Server (NTRS)

    Onwubiko, Chinyere; Onyebueke, Landon

    1996-01-01

    This program report is the final report covering all the work done on this project. The goal of this project is technology transfer of methodologies to improve design process. The specific objectives are: 1. To learn and understand the Probabilistic design analysis using NESSUS. 2. To assign Design Projects to either undergraduate or graduate students on the application of NESSUS. 3. To integrate the application of NESSUS into some selected senior level courses in Civil and Mechanical Engineering curricula. 4. To develop courseware in Probabilistic Design methodology to be included in a graduate level Design Methodology course. 5. To study the relationship between the Probabilistic design methodology and Axiomatic design methodology.

  12. Study of design constraints on helicopter noise

    NASA Technical Reports Server (NTRS)

    Sternfeld, H., Jr.; Wiedersum, C. W.

    1979-01-01

    A means of estimating the noise generated by a helicopter main rotor using information which is generally available during the preliminary design phase of aircraft development is presented. The method utilizes design charts and tables which do not require an understanding of acoustical theory or computational procedures in order to predict the perceived noise level, a weighted sound pressure level, or C weighted sound pressure level of a single hovering rotor. A method for estimating the effective perceived noise level in forward flight is also included. In order to give the designer an assessment of the relative rotor performance, which may be traded off against noise, an additional chart for estimating the percent of available rotor thrust which must be expended in lifting the rotor and drive system, is included as well as approach for comparing the subjective acceptability of various rotors once the absolute sound pressure levels are predicted.

  13. Preliminary design study. Shuttle modular scanning spectroradiometer

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Fundamental concepts on which to base a detailed design for a Shuttle Modular Scanning Spectroradiometer were developed, and a preliminary design is presented. The recommended design features modularity and flexibility. It includes a 75-cm f/1.7-telescope assembly in an all-reflective Schmidt configuration, a solid state scan system (pushbroom) with high resolution over a 15 deg field of view, and ten detector channels covering the spectral range from 0.45 to 12.5 micrometers. It uses charge transfer device techniques to accommodate a large number of detector elements for earth observation measurements. Methods for in-flight radiometric calibration, for image motion compensation, and for data processing are described. Recommendations for ground support equipment are included, and interfaces with the shuttle orbiter vehicle are illustrated.

  14. Design Study for a Mars Geyser Hopper

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Oleson, Steven J.; McGuire, Melissa

    2012-01-01

    The Mars Geyser Hopper is a design reference missions (DRMs) for a Discovery-class spacecraft using Advanced Stirling Radioisotope Generator (ASRG) power source. The Geyser Hopper is a mission concept that will investigate the springtime carbon-dioxide geysers found in regions around the south pole of Mars. The Geyser Hopper design uses Phoenix heritage systems and approach, but uses a single ASRG as the power source, rather than twin solar arrays, and is designed to last over a one-year stay on the South Pole. The spacecraft will land at a target landing area near the south pole of Mars, and have the ability to "hop" after a summertime landing to reposition itself close to a geyser site, and wait through the winter until the first sunlight of spring to witness first-hand the geyser phenomenon.

  15. Detector design studies for Turkish Accelerator Center

    NASA Astrophysics Data System (ADS)

    Aksu, Burçin; Piliçer, Ercan

    2017-02-01

    The proposed Particle Factory detector at Turkish Accelerator Center (TAC-PF) aims to search for charm physics, CP violation and mixing of D0 mesons as well as new physics effects by investigating head-on collisions of 1 GeV electron from Energy Recovery Linac (ERL) with 3.56 GeV positrons from synchrotron storage ring. In this work, we constructed the TAC-PF detector design by using a recently developed framework namely Detector Description for High Energy Physics (DD4hep). The baseline TAC-PF detector design and its qualifications were summarized, followed by a general description.

  16. Advanced EVA system design requirements study

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Design requirements and criteria for the Space Station Advanced Extravehicular Activity System (EVAS) including crew enclosures, portable life support systems, maneuvering propulsion systems, and related extravehicular activity (EVA) support equipment were defined and established. The EVA mission requirements, environments, and medical and physiological requirements, as well as opertional, procedures, and training issues were considered.

  17. Design study of plastic film heat exchanger

    NASA Astrophysics Data System (ADS)

    Guyer, E. C.; Brownell, D. L.

    1986-02-01

    This report presents the results of an effort to develop and design a unique thermoplastic film heat exchanger for use in an industrial heat pump evaporator system and other energy recovery applications. The concept for the exchanger is that of individual heat exchange elements formed by two adjoining and freely hanging plastic films. Liquid flows downward in a regulated fashion between the films due to the balance of hydrostatic and frictional forces. The fluid stream on the outside of film may be a free-falling liquid film, a condensing gas, or a noncondensing gas. The flow and structural principles are similar to those embodied in an earlier heat exchange system developed for use in waste water treatment systems (Sanderson). The design allows for high heat transfer rates while working within the thermal and structural limitations of thermoplastic materials. The potential of this new heat exchanger design lies in the relatively low cost of plastic film and the high inherent corrosion and fouling resistance. This report addresses the selection of materials, the potential heat transf er performance, the mechanical design and operation of a unit applied in a low pressure steam recovery system, and the expected selling price in comparison to conventional metallic shell and tube heat exchangers.

  18. Feasibility study of an Integrated Program for Aerospace vehicle Design (IPAD). Volume 4: IPAD system design

    NASA Technical Reports Server (NTRS)

    Goldfarb, W.; Carpenter, L. C.; Redhed, D. D.; Hansen, S. D.; Anderson, L. O.; Kawaguchi, A. S.

    1973-01-01

    The computing system design of IPAD is described and the requirements which form the basis for the system design are discussed. The system is presented in terms of a functional design description and technical design specifications. The functional design specifications give the detailed description of the system design using top-down structured programming methodology. Human behavioral characteristics, which specify the system design at the user interface, security considerations, and standards for system design, implementation, and maintenance are also part of the technical design specifications. Detailed specifications of the two most common computing system types in use by the major aerospace companies which could support the IPAD system design are presented. The report of a study to investigate migration of IPAD software between the two candidate 3rd generation host computing systems and from these systems to a 4th generation system is included.

  19. Preliminary design studies of an advanced general aviation aircraft

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Preliminary design studies are presented for an advanced general aviation aircraft. Advanced guidance and display concepts, laminar flow, smart structures, fuselage and wing structural design and manufacturing, and preliminary configuration design are discussed. This project was conducted as a graduate level design class under the auspices of the KU/NASA/USRA Advanced Design Program in Aeronautics. The results obtained during the fall semester of 1990 (Phase 1) and the spring semester of 1991 (Phase 2) are presented.

  20. User Design: A Case Study on Corporate Change

    ERIC Educational Resources Information Center

    Pastore, Raymond S.; Carr-Chellman, Alison A.; Lohmann, Neal

    2011-01-01

    The purpose of this study was to examine the effects of implementing user design strategies within the corporate culture. Using a case study design approach, this article explores the change process within a "Fortune" 100 company in which users were given significant decision-making powers. The main focus is on the unique nature of user design in…

  1. Study Design in fMRI: Basic Principles

    ERIC Educational Resources Information Center

    Amaro, Edson, Jr.; Barker, Gareth J.

    2006-01-01

    There is a wide range of functional magnetic resonance imaging (fMRI) study designs available for the neuroscientist who wants to investigate cognition. In this manuscript we review some aspects of fMRI study design, including cognitive comparison strategies (factorial, parametric designs), and stimulus presentation possibilities (block,…

  2. Crossover versus parallel designs: dose-escalation design comparisons for first-in-human studies.

    PubMed

    Yan, Zhiwu; Hosmane, Balakrishna; Locke, Charles

    2013-01-01

    We study the statistical efficiency for rising-dose designs in the context of first-in-human studies. Specifically, we identify a class of crossover designs that are appealing in terms of both subject safety and statistical efficiency and, for a three-period, two-panel design in such a class, we compare its A-efficiency relative to the corresponding parallel designs and optimal/efficient crossover designs, respectively, under various plausible models. In the meantime, we also evaluate the impact of inclusion of baseline measurements as a covariate in the statistical analysis, for both crossover and parallel studies.

  3. Phase A design study of microgravity fluoride fiber puller

    NASA Technical Reports Server (NTRS)

    Workman, Gary L.; Smith, Guy A.; Kosten, Susan

    1994-01-01

    Improved transmission properties for fluoride fibers due to space processing has great potential for commercial benefits. Phase A design study will determine conceptual feasibility and provide initial definition of the technical requirements and design issues for space.

  4. A hingeless rotor XV-15 design integration feasibility study. Volume 1: Engineering design studies

    NASA Technical Reports Server (NTRS)

    Magee, J. P.; Alexander, H. R.

    1978-01-01

    A design integration feasibility study was carried out to investigate what modifications to the basic XV-15 were necessary to accomplish a flight demonstration of the XV-15 with a Boeing hingeless rotor. Also investigated were additional modifications which would exploit the full capability provided by the combination of the new rotor and the existing T53 engine. An evaluation of the aircraft is presented and the data indicate improved air vehicle performance, acceptable aeroelastic margins, lower noise levels and improved flying qualities compared with the XV-15 aircraft. Inspection of the rotor system data provided shows an essentially unlimited life rotor for the flight spectrum anticipated for the XV-15.

  5. Techniques for Conducting Effective Concept Design and Design-to-Cost Trade Studies

    NASA Technical Reports Server (NTRS)

    Di Pietro, David A.

    2015-01-01

    Concept design plays a central role in project success as its product effectively locks the majority of system life cycle cost. Such extraordinary leverage presents a business case for conducting concept design in a credible fashion, particularly for first-of-a-kind systems that advance the state of the art and that have high design uncertainty. A key challenge, however, is to know when credible design convergence has been achieved in such systems. Using a space system example, this paper characterizes the level of convergence needed for concept design in the context of technical and programmatic resource margins available in preliminary design and highlights the importance of design and cost evaluation learning curves in determining credible convergence. It also provides techniques for selecting trade study cases that promote objective concept evaluation, help reveal unknowns, and expedite convergence within the trade space and conveys general practices for conducting effective concept design-to-cost studies.

  6. Reusable Reentry Satellite (RRS) system design study

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The Reusable Reentry Satellite (RRS) is intended to provide investigators in several biological disciplines with a relatively inexpensive method to access space for up to 60 days with eventual recovery on Earth. The RRS will permit totally intact, relatively soft, recovery of the vehicle, system refurbishment, and reflight with new and varied payloads. The RRS is to be capable of three reflights per year over a 10-year program lifetime. The RRS vehicle will have a large and readily accessible volume near the vehicle center of gravity for the Payload Module (PM) containing the experiment hardware. The vehicle is configured to permit the experimenter late access to the PM prior to launch and rapid access following recovery. The RRS will operate in one of two modes: (1) as a free-flying spacecraft in orbit, and will be allowed to drift in attitude to provide an acceleration environment of less than 10(exp -5) g. the acceleration environment during orbital trim maneuvers will be less than 10(exp -3) g; and (2) as an artificial gravity system which spins at controlled rates to provide an artificial gravity of up to 1.5 Earth g. The RRS system will be designed to be rugged, easily maintained, and economically refurbishable for the next flight. Some systems may be designed to be replaced rather than refurbished, if cost effective and capable of meeting the specified turnaround time. The minimum time between recovery and reflight will be approximately 60 days. The PMs will be designed to be relatively autonomous, with experiments that require few commands and limited telemetry. Mass data storage will be accommodated in the PM. The hardware development and implementation phase is currently expected to start in 1991 with a first launch in late 1993.

  7. Conceptual Design Studies of Composite AMST

    DTIC Science & Technology

    1974-10-01

    AND EMPENNAGE BOX STRUCTURE AND FUSELAGE SHELL A’PLICATIONS WERE EMPHASIZED TOGETHER WITH SELECTED APPLICATIONS IN SECONDARY STRUCTURES TO REDUCE THE...WAS A SANDWICH.PANEL MULTICELL DESIGN (ASSEMBLED THROUGH THE USE OF INTERNAL PRESSURE BAGS), AND THE FUSELAGE SHELL WAS AN AUTOMATICALLY TAPE-WRAPPED...WWAIMi a , LU 0 U caaIr U. 0 IL ..- U). Lu 0 z t (A z us k 4 wint and nip,.nnige box structures and the fuselage shell . The selected tresin cont pts were

  8. Statistical design study of lunar ceramic

    NASA Technical Reports Server (NTRS)

    Effinger, Mike; Tucker, Dennis

    1994-01-01

    Fabrication of a lunar ceramic was conducted according to a statistically designed experiment. The method of cold pressing was used since the consumption of electrical energy is kept to a minimum (a priority in the lunar environment). This traditional fabrication technique also provides an initial data source on which further investigations can be based. Results obtained from using two percent binder, a cold pressing pressure of 276 MPa, and 24 hours sintering time yielded the greatest compressive strength of 247 MPa. Analysis of each variable's influence on the compressive strength is also presented.

  9. Liquid Acquisition Device Design Sensitivity Study

    NASA Technical Reports Server (NTRS)

    VanDyke, M. K.; Hastings, L. J.

    2012-01-01

    In-space propulsion often necessitates the use of a capillary liquid acquisition device (LAD) to assure that gas-free liquid propellant is available to support engine restarts in microgravity. If a capillary screen-channel device is chosen, then the designer must determine the appropriate combination screen mesh and channel geometry. A screen mesh selection which results in the smallest LAD width when compared to any other screen candidate (for a constant length) is desirable; however, no best screen exists for all LAD design requirements. Flow rate, percent fill, and acceleration are the most influential drivers for determining screen widths. Increased flow rates and reduced percent fills increase the through-the-screen flow pressure losses, which drive the LAD to increased widths regardless of screen choice. Similarly, increased acceleration levels and corresponding liquid head pressures drive the screen mesh selection toward a higher bubble point (liquid retention capability). After ruling out some screens on the basis of acceleration requirements alone, candidates can be identified by examining screens with small flow-loss-to-bubble point ratios for a given condition (i.e., comparing screens at certain flow rates and fill levels). Within the same flow rate and fill level, the screen constants inertia resistance coefficient, void fraction, screen pore or opening diameter, and bubble point can become the driving forces in identifying the smaller flow-loss-to-bubble point ratios.

  10. Wind study for high altitude platform design

    NASA Technical Reports Server (NTRS)

    Strganac, T. W.

    1979-01-01

    An analysis of upper air winds was performed to define the wind environment at potential operating altitudes for high altitude powered platform concepts. Wind conditions of the continental United States, Pacific area (Alaska to Sea of Japan), and European area (Norwegian and Mediterranean Sea) were obtained using a representative network of sites selected based upon adequate high altitude sampling, geographic dispersion, and observed upper wind patterns. A data base of twenty plus years of rawinsonde gathered wind information was used in the analysis. Annual variations from surface to 10 mb pressure altitude were investigated to encompass the practical operating range for the platform concepts. Parametric analysis for the United States and foreign areas was performed to provide a basis for vehicle system design tradeoffs. This analysis of wind magnitudes indicates the feasibility of annual operation at a majority of sites and more selective seasonal operation for the extreme conditions between the pressure altitudes of 100 to 25 mb based upon the assumed design speeds.

  11. Innovative Offshore Wind Plant Design Study

    SciTech Connect

    Hurley, William L.; Nordstrom, Charles J.; Morrison, Brent J.

    2013-12-18

    Technological advancements in the Glosten PelaStar floating wind turbine system have led to projected cost of energy (COE) reductions from today’s best-in-class offshore wind systems. The PelaStar system is projected to deliver a COE that is 35% lower than that delivered by the current offshore wind plants. Several technology developments have been achieved that directly target significant cost of energy reductions. These include: Application of state-of-the-art steel construction materials and methods, including fatigue-resistant welding techniques and technologies, to reduce hull steel weight; Advancements in synthetic fiber tendon design for the mooring system, which are made possible by laboratory analysis of full-scale sub-rope specimens; Investigations into selected anchor technologies to improve anchor installation methods; Refinement of the installation method, specifically through development of the PelaStar Support Barge design. Together, these technology developments drive down the capital cost and operating cost of offshore wind plants and enable access to superb wind resources in deep water locations. These technology developments also reduce the uncertainty of the PelaStar system costs, which increases confidence in the projected COE reductions.

  12. Study design in osteoporosis: a European perspective.

    PubMed

    Kanis, J A; Alexandre, J M; Bone, H G; Abadie, E; Brasseur, D; Chassany, O; Durrleman, S; Lekkerkerker, J F F; Caulin, F

    2003-06-01

    The advent of effective agents for the treatment of osteoporosis has led to the view that placebo-controlled trials to test new agents for efficacy are no longer appropriate. Rather, studies of superiority, equivalence, or non-inferiority have been recommended. Such studies require very large sample sizes, and the burden of osteoporotic fracture in a trial setting is substantially increased. Studies of equivalence cannot be unambiguously interpreted because the variance in effect of active comparator agents is too large in osteoporosis. If fracture studies are required by regulatory agencies, there is still a requirement for placebo-controlled studies, although perhaps of shorter duration than demanded at present.

  13. Parametric Design Studies on a Direct Liquid Feed Fuel Cell

    NASA Technical Reports Server (NTRS)

    Frank, H. A.; Narayanan, S. R.; Nakamura, B.; Surampudi, S.; Halpert, G.

    1995-01-01

    Parametric design studies were carried out on a direct methanol liquid feed fuel cell employing 1 M MeOH fuel, air and oxygen as oxidant in a 2 inch x 2 inch cell employing polymeric electrolyte membranes. Measurements include voltage-current output parameters, methanol crossover rate, and impedance as a function of several design and operational variables. Design variables are described.

  14. Embracing Wicked Problems: The Turn to Design in Composition Studies

    ERIC Educational Resources Information Center

    Marback, Richard

    2009-01-01

    Recent appeal to the concept of design in composition studies benefits teaching writing in digital media. Yet the concept of design has not been developed enough to fully benefit composition instruction. This article develops an understanding of design as a matter of resolving wicked problems and makes a case for the advantages of this…

  15. Scaffolding Preservice Teachers' WebQuest Design: A Qualitative Study

    ERIC Educational Resources Information Center

    Wang, Feng; Hannafin, Michael J.

    2009-01-01

    This study examined how participating preservice teachers reported their perceptions and use of different scaffolds provided to support their WebQuest design. Sixteen preservice teachers participated in a succession of course activities designed to guide WebQuest design and development. Results indicated that while participants followed, adapted,…

  16. Study on Product Innovative Design Process Driven by Ideal Solution

    NASA Astrophysics Data System (ADS)

    Zhang, Fuying; Lu, Ximei; Wang, Ping; Liu, Hui

    Product innovative design in companies today relies heavily on individual members’ experience and creative ideation as well as their skills of integrating creativity and innovation tools with design methods agilely. Creative ideation and inventive ideas generation are two crucial stages in product innovative design process. Ideal solution is the desire final ideas for given problem, and the striving reaching target for product design. In this paper, a product innovative design process driven by ideal solution is proposed. This design process encourages designers to overcome their psychological inertia, to foster creativity in a systematic way for acquiring breakthrough creative and innovative solutions in a reducing sphere of solution-seeking, and results in effective product innovative design rapidly. A case study example is also presented to illustrate the effectiveness of the proposed design process.

  17. Spacecraft (Mobile Satellite) configuration design study

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The relative costs to procure and operate a two-satellite mobile satellite system designed to operate either in the UHF band of the L Band, and with several antenna diameter options in each frequency band was investigated. As configured, the size of the spacecraft is limited to the current RCA Series 4000 Geosynchronous Communications Spacecraft bus, which spans the range from 4000 to 5800 pounds in the transfer orbit. The Series 4000 bus forms the basis around which the Mobile Satellite transponder and associated antennas were appended. Although the resultant configuration has little outward resemblance to the present Series 4000 microwave communications spacecraft, the structure, attitude control, thermal, power, and command and control subsystems of the Series 4000 spacecraft are all adapted to support the Mobile Satellite mission.

  18. Current status of high conversion pressurized water reactor design studies

    SciTech Connect

    Umeoka, T.; Kono, T.; Toyoda, Y.; Ogino, M.; Iwai, S.; Hishida, H.

    1988-01-01

    Preliminary design studies on high conversion pressurized water reactors (HCPWRs) have been completed, and plant design studies are currently being performed to improve the feasibility of HCPWRs. The present status of the feasibility studies is covered, and the related validation tests to be conducted in the coming years are reviewed.

  19. Optimal adaptive sequential designs for crossover bioequivalence studies.

    PubMed

    Xu, Jialin; Audet, Charles; DiLiberti, Charles E; Hauck, Walter W; Montague, Timothy H; Parr, Alan F; Potvin, Diane; Schuirmann, Donald J

    2016-01-01

    In prior works, this group demonstrated the feasibility of valid adaptive sequential designs for crossover bioequivalence studies. In this paper, we extend the prior work to optimize adaptive sequential designs over a range of geometric mean test/reference ratios (GMRs) of 70-143% within each of two ranges of intra-subject coefficient of variation (10-30% and 30-55%). These designs also introduce a futility decision for stopping the study after the first stage if there is sufficiently low likelihood of meeting bioequivalence criteria if the second stage were completed, as well as an upper limit on total study size. The optimized designs exhibited substantially improved performance characteristics over our previous adaptive sequential designs. Even though the optimized designs avoided undue inflation of type I error and maintained power at ≥ 80%, their average sample sizes were similar to or less than those of conventional single stage designs.

  20. Computational wing design studies relating to natural laminar flow

    NASA Technical Reports Server (NTRS)

    Waggoner, Edgar G.

    1986-01-01

    Two research studies are described which directly relate to the application of natural laminar flow (NLF) technology to transonic transport-type wing planforms. Each involved using state-of-the-art computational methods to design three-dimensional wing contours which generate significant runs of favorable pressure gradients. The first study supported the Variable Sweep Transition Flight Experiment and involves design of a full-span glove which extends from the leading edge to the spoiler hinge line on the upper surface of an F-14 outer wing panel. A wing was designed computationally for a corporate transport aircraft in the second study. The resulting wing design generated favorable pressure gradients from the leading edge aft to the mid-chord on both upper and lower surfaces at the cruise design point. Detailed descriptions of the computational design approach are presented along with the various constraints imposed on each of the designs.

  1. Study of the Synchronous Reluctance Motor Design

    NASA Astrophysics Data System (ADS)

    Dirba, J.; Lavrinovicha, L.; Dobriyan, R.

    2016-08-01

    The paper focuses on studying the external-rotor synchronous reluctance motor. The analysis is performed to estimate the influence of the number of stator slots and non-magnetic areas in the rotor (i.e., flux barriers) on the electromagnetic torque and torque ripple of the studied motor. It is concluded that the increase in the number of stator slots Z = 6 to Z = 18 causes an approximately twofold decrease in the ripple factor, but torque increases by 5 %. Electromagnetic torque will be increased approximately by 24 %, if non-magnetic flux barriers are created in the rotor of the studied synchronous reluctance motor.

  2. Cometary particulate analyzer design definition study

    NASA Technical Reports Server (NTRS)

    Utterback, N. G.

    1981-01-01

    A concept for remotely determining the relative abundance of elements contained in cometary particulates collected by a spacecraft was conducted with very encouraging results. The technique utilizes a short high intensity burst of laser radiation to vaporize and ionize collected particulate material. Ions extracted from this laser-produced plasma are analyzed in a time of flight mass spectrometer to yield an atomic mass spectrum representative of the relative abundance of elements in the particulates. A prototype analyzer system was designed, constructed, and tested. Results show that: (1) energy-time focus performs as predicted in improving resolution; (2) power densities sufficient to produce usable ionization efficiencies can be obtained; (3) complex alloys such as stainless steel can be analyzed; and (4) a tiny, simple and reliable laser used in the demonstration easily meets spacecraft power and mass limitations. A mass resolution of 150 was experimentally demonstrated at mass 108, and an analytical extrapolation predicts a resolution sufficient to separate masses 250 and 251.

  3. Some considerations on the design of population pharmacokinetic studies.

    PubMed

    Duffull, Stephen; Waterhouse, Tim; Eccleston, John

    2005-08-01

    The goal of this manuscript is to introduce a framework for consideration of designs for population pharmacokinetic orpharmacokinetic-pharmacodynamic studies. A standard one compartment pharmacokinetic model with first-order input and elimination is considered. A series of theoretical designs are considered that explore the influence of optimizing the allocation of sampling times, allocating patients to elementary designs, consideration of sparse sampling and unbalanced designs and also the influence of single vs. multiple dose designs. It was found that what appears to be relatively sparse sampling (less blood samples per patient than the number of fixed effects parameters to estimate) can also be highly informative. Overall, it is evident that exploring the population design space can yield many parsimonious designs that are efficient for parameter estimation and that may not otherwise have been considered without the aid of optimal design theory.

  4. Combining genetic association study designs: a GWAS case study

    PubMed Central

    Estus, Janice L.; Fardo, David W.

    2013-01-01

    Genome-wide association studies (GWAS) explore the relationship between genome variability and disease susceptibility with either population- or family-based data. Here, we have evaluated the utility of combining population- and family-based statistical association tests and have proposed a method for reducing the burden of multiple testing. Unrelated singleton and parent-offspring trio cases and controls from the Genetics of Kidneys in Diabetes (GoKinD) study were analyzed for genetic association with diabetic nephropathy (DN) in type 1 diabetics (T1D). The Cochran-Armitage test for trend and the family-based association test were employed using either unrelated cases and controls or trios, respectively. In addition to combining single nucleotide polymorphism (SNP) p-values across these tests via Fisher's method, we employed a novel screening approach to rank SNPs based on conditional power for more efficient testing. Using either the population-based or family-based subset alone predictably limited resolution to detect DN SNPs. For 384,197 SNPs passing quality control (QC), none achieved strict genome-wide significance (1.4 × 10−7) using 1171 singletons (577/594 cases/controls) or 1738 pooled singletons and offspring probands (841/897). Similarly, none of the 352,004 SNPs passing QC in 567 family trios (264/303 case/control proband trios) reached genome-wide significance. Testing the top 10 SNPs ranked using aggregated conditional power resulted in two SNPs reaching genome-wide significance, rs11645147 on chromosome 16 (p = 1.74 × 10−4 < 0.05/10 = 0.005) and rs7866522 on chromosome 9 (p = 0.0033). Efficient usage of mixed designs incorporating both unrelated and family-based data may help to uncover associations otherwise difficult to detect in the presence of massive multiple testing corrections. Capitalizing on the strengths of both types while using screening approaches may be useful especially in light of large-scale, next-generation sequencing and rare

  5. FFAG Designs for the International Design Study for the Neutrino Factory

    SciTech Connect

    Berg, J.S.; Machida, S.

    2009-05-04

    The International Design Study for the Neutrino Factory (IDS-NF) aims to produce a design report for a neutrino factory. One component of that design is a linear nonscaling fixed-field alternating gradient accelerator (FFAG) that will accelerate to the final energy of 25 GeV. An FFAG is used to reduce the machine cost by maximizing the number of passes made through the RF cavities. We present some design options for this FFAG, individually optimized for cost. We study the addition of nonlinear magnets to the lattice to improve the performance of the lattice and consider the negative effects of doing so.

  6. Research study on IPS digital controller design

    NASA Technical Reports Server (NTRS)

    Kuo, B. C.; Folkerts, C.

    1976-01-01

    The performance is investigated of the simplified continuous-data model of the Instrument Pointing System (IPS). Although the ultimate objective is to study the digital model of the system, knowledge on the performance of the continuous-data model is important in the sense that the characteristics of the digital system should approach those of the continuous-data system as the sampling period approaches zero.

  7. Preliminary design studies of an advanced general aviation aircraft

    NASA Technical Reports Server (NTRS)

    Barrett, Ron; Demoss, Shane; Dirkzwager, AB; Evans, Darryl; Gomer, Charles; Keiter, Jerry; Knipp, Darren; Seier, Glen; Smith, Steve; Wenninger, ED

    1991-01-01

    The preliminary design results are presented of the advanced aircraft design project. The goal was to take a revolutionary look into the design of a general aviation aircraft. Phase 1 of the project included the preliminary design of two configurations, a pusher, and a tractor. Phase 2 included the selection of only one configuration for further study. The pusher configuration was selected on the basis of performance characteristics, cabin noise, natural laminar flow, and system layouts. The design was then iterated to achieve higher levels of performance.

  8. An analytical study for the design of advanced rotor airfoils

    NASA Technical Reports Server (NTRS)

    Kemp, L. D.

    1973-01-01

    A theoretical study has been conducted to design and evaluate two airfoils for helicopter rotors. The best basic shape, designed with a transonic hodograph design method, was modified to meet subsonic criteria. One airfoil had an additional constraint for low pitching-moment at the transonic design point. Airfoil characteristics were predicted. Results of a comparative analysis of helicopter performance indicate that the new airfoils will produce reduced rotor power requirements compared to the NACA 0012. The hodograph design method, written in CDC Algol, is listed and described.

  9. A Study of Head Start Effectiveness Using a Randomized Design.

    ERIC Educational Resources Information Center

    Abbott-Shim, Martha; Lambert, Richard; McCart, Frances

    Although an extensive body of literature exists on the impact of Head Start, very few studies have used an experimental design with random assignment, a key methodological component needed to increase the weight of evaluation findings. This study used a randomized design with a wide range of outcomes related to school readiness to assess the…

  10. Children as Educational Computer Game Designers: An Exploratory Study

    ERIC Educational Resources Information Center

    Baytak, Ahmet; Land, Susan M.; Smith, Brian K.

    2011-01-01

    This study investigated how children designed computer games as artifacts that reflected their understanding of nutrition. Ten 5th grade students were asked to design computer games with the software "Game Maker" for the purpose of teaching 1st graders about nutrition. The results from the case study show that students were able to…

  11. Preliminary design study for an atomospheric science facility

    NASA Technical Reports Server (NTRS)

    Hutchison, R.

    1972-01-01

    The activities and results of the Atmospheric Science Facility preliminary design study are reported. The objectives of the study were to define the scientific goals, to determine the range of experiment types, and to develop the preliminary instrument design requirements for a reusable, general purpose, optical research facility for investigating the earth's atmosphere from a space shuttle orbital vehicle.

  12. Interior Design Supports Art Education: A Case Study

    ERIC Educational Resources Information Center

    Clemons, Stephanie A.

    2006-01-01

    Interior design, as a field of study, is a rapidly growing area of interest--particularly for teenagers in the United States. Part of this interest stems from the proliferation of design-related reality shows available through television media. Some art educators and curriculum specialists in the nation perceive the study of interior spaces as a…

  13. Communicating Qualitative Research Study Designs to Research Ethics Review Boards

    ERIC Educational Resources Information Center

    Ells, Carolyn

    2011-01-01

    Researchers using qualitative methodologies appear to be particularly prone to having their study designs called into question by research ethics or funding agency review committees. In this paper, the author considers the issue of communicating qualitative research study designs in the context of institutional research ethics review and offers…

  14. Study of new anticoincidence systems design

    NASA Astrophysics Data System (ADS)

    Chabaud, J.; Laurent, P.; Baronick, J.-P.; Oger, R.; Prévôt, G.

    2012-12-01

    The scientific performances of future hard X-ray missions will necessitate a very low detector background level. This will imply thorough background simulations, and efficient background rejection systems. It necessitates also a very good knowledge of the detectors to be shielded. We got experience on these activities by conceiving and optimizing the active and passive background rejection system of the Simbol-X and IXO/HXI missions. Considering that this work may naturally be extended to other X-ray missions, we have initiated with CNES, in 2010, a R&T project on the study of background rejection systems, whose status will be presented in this paper.

  15. Interactive computer program for optimal designs of longitudinal cohort studies.

    PubMed

    Tekle, Fetene B; Tan, Frans E S; Berger, Martijn P F

    2009-05-01

    Many large scale longitudinal cohort studies have been carried out or are ongoing in different fields of science. Such studies need a careful planning to obtain the desired quality of results with the available resources. In the past, a number of researches have been performed on optimal designs for longitudinal studies. However, there was no computer program yet available to help researchers to plan their longitudinal cohort design in an optimal way. A new interactive computer program for the optimization of designs of longitudinal cohort studies is therefore presented. The computer program helps users to identify the optimal cohort design with an optimal number of repeated measurements per subject and an optimal allocations of time points within a given study period. Further, users can compute the loss in relative efficiencies of any other alternative design compared to the optimal one. The computer program is described and illustrated using a practical example.

  16. Research designs and making causal inferences from health care studies.

    PubMed

    Flannelly, Kevin J; Jankowski, Katherine R B

    2014-01-01

    This article summarizes the major types of research designs used in healthcare research, including experimental, quasi-experimental, and observational studies. Observational studies are divided into survey studies (descriptive and correlational studies), case-studies and analytic studies, the last of which are commonly used in epidemiology: case-control, retrospective cohort, and prospective cohort studies. Similarities and differences among the research designs are described and the relative strength of evidence they provide is discussed. Emphasis is placed on five criteria for drawing causal inferences that are derived from the writings of the philosopher John Stuart Mill, especially his methods or canons. The application of the criteria to experimentation is explained. Particular attention is given to the degree to which different designs meet the five criteria for making causal inferences. Examples of specific studies that have used various designs in chaplaincy research are provided.

  17. Design of Orion Soil Impact Study using the Modern Design of Experiments

    NASA Technical Reports Server (NTRS)

    DeLoach, Richard

    2010-01-01

    Two conventional One Factor At a Time (OFAT) test matrices under consideration for an Orion Landing System subscale soil impact study are reviewed. Certain weaknesses in the designs, systemic to OFAT experiment designs generally, are identified. An alternative test matrix is proposed that is based in the Modern Design of Experiments (MDOE), which achieves certain synergies by combining the original two test matrices into one. The attendant resource savings are quantified and the impact on uncertainty is discussed.

  18. Design Evolution Study Thermal Operating Methodology

    SciTech Connect

    T.L. Mitchell

    2002-04-29

    This study provides results supporting the conclusion that the repository can be operated over a varying range of thermal modes and therefore temperatures. In particular, this work focused on limiting the peak, postclosure waste package surface temperature to less than 85 degrees Celsius, a possible limit due to corrosion considerations. These operating modes were compared by varying the waste package in drift spacing (0.1-2.83 meters), drift pitch (drift spacing centerline to centerline of 40-120 meters), ventilation duration (75-300 years), and ventilation efficiency (50-80%). The resulting graphical representation shows where the constant temperature of the waste package (85 degrees Celsius) lies with respect to drift pitch and waste package spacing. The waste considered in this study is the strict youngest fuel first 5 years old fuel. Using only strict youngest fuel first 5 years old fuel in the waste stream results in an average heat load per waste package of 12.48kW/Pkg. With this high average heat load, it is not possible to achieve a maximum waste package surface temperature of 85 degrees Celsius or less. By aging 63% of the strict youngest fuel first 5 years old fuel for 27 years, it becomes possible to maintain the waste package surface temperature at 85 degrees Celsius or less. The 27 years of aging comes from the fact that the repository could be closed in as little as 50 years. It takes 23 years to emplace the waste and therefore the last fuel received for emplacement is 27 years prior to closures. The strict youngest fuel first 5 years old fuel waste stream with 63% aged for 27 years, results in an average power level of 8.4kW/Pkg. This lower heat load allows the controlled parameters of drift pitch, waste package spacing, aging, and ventilation duration to be varied to achieve the desired results. This study compares the hot strict youngest fuel first 5 years old fuel to the previous waste stream, which has an average of 26-year-old fuel. The 26-year

  19. On study design in neuroimaging heritability analyses

    NASA Astrophysics Data System (ADS)

    Koran, Mary Ellen; Li, Bo; Jahanshad, Neda; Thornton-Wells, Tricia A.; Glahn, David C.; Thompson, Paul M.; Blangero, John; Nichols, Thomas E.; Kochunov, Peter; Landman, Bennett A.

    2014-03-01

    Imaging genetics is an emerging methodology that combines genetic information with imaging-derived metrics to understand how genetic factors impact observable structural, functional, and quantitative phenotypes. Many of the most well-known genetic studies are based on Genome-Wide Association Studies (GWAS), which use large populations of related or unrelated individuals to associate traits and disorders with individual genetic factors. Merging imaging and genetics may potentially lead to improved power of association in GWAS because imaging traits may be more sensitive phenotypes, being closer to underlying genetic mechanisms, and their quantitative nature inherently increases power. We are developing SOLAR-ECLIPSE (SE) imaging genetics software which is capable of performing genetic analyses with both large-scale quantitative trait data and family structures of variable complexity. This program can estimate the contribution of genetic commonality among related subjects to a given phenotype, and essentially answer the question of whether or not the phenotype is heritable. This central factor of interest, heritability, offers bounds on the direct genetic influence over observed phenotypes. In order for a trait to be a good phenotype for GWAS, it must be heritable: at least some proportion of its variance must be due to genetic influences. A variety of family structures are commonly used for estimating heritability, yet the variability and biases for each as a function of the sample size are unknown. Herein, we investigate the ability of SOLAR to accurately estimate heritability models based on imaging data simulated using Monte Carlo methods implemented in R. We characterize the bias and the variability of heritability estimates from SOLAR as a function of sample size and pedigree structure (including twins, nuclear families, and nuclear families with grandparents).

  20. Transitioning from Marketing-Oriented Design to User-Oriented Design: A Case Study

    ERIC Educational Resources Information Center

    Laster, Shari; Stitz, Tammy; Bove, Frank J.; Wise, Casey

    2011-01-01

    The transition to a new architecture and design for an academic library Web site does not always proceed smoothly. In this case study, a library at a large research university hired an outside Web development contractor to create a new architecture and design for the university's Web site using dotCMS, an open-source content management system. The…

  1. Design Fixation and Cooperative Learning in Elementary Engineering Design Project: A Case Study

    ERIC Educational Resources Information Center

    Luo, Yi

    2015-01-01

    This paper presents a case study examining 3rd, 4th and 5th graders' design fixation and cooperative learning in an engineering design project. A mixed methods instrument, the Cooperative Learning Observation Protocol (CLOP), was adapted to record frequency and class observation on cooperative learning engagement through detailed field notes.…

  2. Advanced wind turbine design studies: Advanced conceptual study. Final report

    SciTech Connect

    Hughes, P; Sherwin, R

    1994-08-01

    In conjunction with the US Department of Energy and the National Renewable Energy Laboratory`s Advanced Wind Turbine Program, the Atlantic Orient Corporation developed preliminary designs for the next generation of wind turbines. These 50 kW and 350 kW turbines are based upon the concept of simplicity. By adhering to a design philosophy that emphasizes simplicity, we project that these turbines will produce energy at extremely competitive rates which will unlock the potential of wind energy domestically and internationally. The program consisted of three distinct phases. First, we evaluated the operational history of the Enertech 44 series wind turbines. As a result of this evaluation, we developed, in the second phase, a preliminary design for a new 50 kW turbine for the near-term market. In the third phase, we took a clean-sheet-of-paper approach to designing a 350 kW turbine focused on the mid-1990s utility market that incorporated past experience and advanced technology.

  3. Advanced wind turbine design studies: Advanced conceptual study

    NASA Astrophysics Data System (ADS)

    Hughes, P.; Sherwin, R.

    1994-08-01

    In conjunction with the US Department of Energy and the National Renewable Energy Laboratory's Advanced Wind Turbine Program, the Atlantic Orient Corporation developed preliminary designs for the next generation of wind turbines. These 50 kW and 350 kW turbines are based upon the concept of simplicity. By adhering to a design philosophy that emphasizes simplicity, we project that these turbines will produce energy at extremely competitive rates which will unlock the potential of wind energy domestically and internationally. The program consisted of three distinct phases. First, we evaluated the operational history of the Enertech 44 series wind turbines. As a result of this evaluation, we developed, in the second phase, a preliminary design for a new 50 kW turbine for the near-term market. In the third phase, we took a clean-sheet-of-paper approach to designing a 350 kW turbine focused on the mid-1990s utility market that incorporated past experience and advanced technology.

  4. WeSaySo Case Study: Designing and Implementing a Case Study for Use in an Instructional Design Class.

    ERIC Educational Resources Information Center

    Graves, Rick; Barnett, Mardee; Gamble, Yolanda; Kolak, Mike

    A case study was used in an instructional design class to facilitate the transfer of conceptual knowledge to concrete concerns and to aid instructional technology graduate students' understanding of the steps involved in designing, analyzing, and implementing an effective needs analysis. The case study involved real events at fictitious company…

  5. Lean, Premixed-Prevaporized (LPP) combustor conceptual design study

    NASA Technical Reports Server (NTRS)

    Dickman, R. A.; Dodds, W. J.; Ekstedt, E. E.

    1979-01-01

    Four combustion systems were designed and sized for the energy efficient engine. A fifth combustor was designed for the cycle and envelope of the twin-spool, high bypass ratio, high pressure ratio turbofan engine. Emission levels, combustion performance, life, and reliability assessments were made for these five combustion systems. Results of these design studies indicate that cruise NOx emission can be reduced by the use of lean, premixed-prevaporaized combustion and airflow modulation.

  6. Instructional Design and Online Learning: A Quality Assurance Study

    ERIC Educational Resources Information Center

    Monroe, Rose M.

    2011-01-01

    The purpose of this study was to investigate the difference in the evaluations of online course quality using the Quality Matters model among four groups of reviewers: instructional designers, faculty with subject-matter expertise, peer faculty with no subject-matter expertise, and administrators. A causal-comparative design was utilized to…

  7. Design study for a magnetically supported reaction wheel

    NASA Technical Reports Server (NTRS)

    Stocking, G.; Dendy, J.; Sabnis, A.

    1974-01-01

    Results are described of a study program in which the characteristics of a magnetically supported reaction wheel are defined. Tradeoff analyses are presented for the principal components, which are then combined in several reaction wheel design concepts. A preliminary layout of the preferred configuration is presented along with calculated design and performance parameters. Recommendations are made for a prototype development program.

  8. Concussion Awareness Education: A Design and Development Research Study

    ERIC Educational Resources Information Center

    Pilbeam, Renee M.

    2016-01-01

    This research study looks at the design and development of an online concussion awareness education module. The Keep Your Head in the Game: Concussion Awareness Training for High School Athletes, or Brainbook, is a stand-alone e-learning module designed to run for fifty minutes and to be highly interactive using short video clips with associated…

  9. Design Languages, Notation Systems, and Instructional Technology: A Case Study

    ERIC Educational Resources Information Center

    Waters, Sandie H.; Gibbons, Andrew S.

    2004-01-01

    Notational systems, used in mature fields of study, are closely related to design languages. The future of a technological field depends on the ability to communicate ideas and changes with others in the field. Instructional technology is one field that can benefit from a notation system enabling designers to duplicate, execute, and communicate…

  10. Pasadena City College SIGI Project Research Design. Pilot Study.

    ERIC Educational Resources Information Center

    Risser, John J.; Tulley, John E.

    A pilot study evaluation of SIGI (System of Interactive Guidance and Information) at Pasadena City College in 1974-75 tested the effectiveness of an experimental research design for an expanded field test of the system the following year. (SIGI is a computer based career guidance program designed by Educational Testing Service to assist community…

  11. Presentation Wizards and You: An Instructional Design Case Study.

    ERIC Educational Resources Information Center

    Savenye, Wilhelmina C.

    1991-01-01

    Presents a case study designed to help intermediate and advanced students or trainees to adapt traditional instructional design procedures to "real-world" training situations. Scenarios involving a video production company and interactive video are described; and learning outcomes are discussed, including conducting a needs assessment,…

  12. Thinking about "Design Thinking": A Study of Teacher Experiences

    ERIC Educational Resources Information Center

    Retna, Kala S.

    2016-01-01

    Schools are continuously looking for new ways of enhancing student learning to equip students with skills that would enable them to cope with twenty-first century demands. One promising approach focuses on design thinking. This study examines teacher's perceptions, experiences and challenges faced in adopting design thinking. There is a lack of…

  13. 23 CFR 650.117 - Content of design studies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 23 Highways 1 2012-04-01 2012-04-01 false Content of design studies. 650.117 Section 650.117 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains §...

  14. 23 CFR 650.117 - Content of design studies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 23 Highways 1 2014-04-01 2014-04-01 false Content of design studies. 650.117 Section 650.117 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains §...

  15. 23 CFR 650.117 - Content of design studies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 23 Highways 1 2013-04-01 2013-04-01 false Content of design studies. 650.117 Section 650.117 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains §...

  16. 23 CFR 650.117 - Content of design studies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Content of design studies. 650.117 Section 650.117 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains §...

  17. 23 CFR 650.117 - Content of design studies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 23 Highways 1 2011-04-01 2011-04-01 false Content of design studies. 650.117 Section 650.117 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains §...

  18. Open Educational Resources: A Delphi Study of Instructional Design Quality

    ERIC Educational Resources Information Center

    Emerson, Marnice K.

    2013-01-01

    The purpose of this modified Delphi research study was to investigate instructional designers' beliefs about the instructional strategies and activities to be included in a universal framework for designing quality, self-directed, multimedia, open educational resources (OERs). With the rapid growth of availability and use of OERs by a widely…

  19. An Empirical Study on Students' Ability to Comprehend Design Patterns

    ERIC Educational Resources Information Center

    Chatzigeorgiou, Alexander; Tsantalis, Nikolaos; Deligiannis, Ignatios

    2008-01-01

    Design patterns have become a widely acknowledged software engineering practice and therefore have been incorporated in the curricula of most computer science departments. This paper presents an observational study on students' ability to understand and apply design patterns. Within the context of a postgraduate software engineering course,…

  20. Neutronic design studies for an unattended, low power reactor

    SciTech Connect

    Palmer, R.G.; Durkee, J.W. Jr.

    1986-01-01

    The Los Alamos National Laboratory is involved in the design and demonstrations of a small, long-lived nuclear heat and electric power source for potential applications at remote sites where alternate fossil energy systems would not be cost effective. This paper describes the neutronic design analysis that was performed to arrive at two conceptual designs, one using thermoelectric conversion, the other using an organic Rankine cycle. To meet the design objectives and constraints a number of scoping and optimization studies were carried out. The results of calculations of control worths, temperature coefficients of reactivity and fuel depletion effects are reported.

  1. Innovative Approaches to Curriculum Design in the Study Abroad Program.

    ERIC Educational Resources Information Center

    Hill, Deborah J., Ed.

    Recommendations for designing a study abroad curriculum are offered to program directors, teachers, and study abroad leaders. The 13 essays and their authors are: "Study Abroad and the Liberal Arts: The Canon in Disarray" (Michael Kline); "Preparing for Study Abroad: Innovative and Traditional Library Resources" (Carolyn…

  2. The Study of the Relationship between Probabilistic Design and Axiomatic Design Methodology. Volume 2

    NASA Technical Reports Server (NTRS)

    Onwubiko, Chin-Yere; Onyebueke, Landon

    1996-01-01

    The structural design, or the design of machine elements, has been traditionally based on deterministic design methodology. The deterministic method considers all design parameters to be known with certainty. This methodology is, therefore, inadequate to design complex structures that are subjected to a variety of complex, severe loading conditions. A nonlinear behavior that is dependent on stress, stress rate, temperature, number of load cycles, and time is observed on all components subjected to complex conditions. These complex conditions introduce uncertainties; hence, the actual factor of safety margin remains unknown. In the deterministic methodology, the contingency of failure is discounted; hence, there is a use of a high factor of safety. It may be most useful in situations where the design structures are simple. The probabilistic method is concerned with the probability of non-failure performance of structures or machine elements. It is much more useful in situations where the design is characterized by complex geometry, possibility of catastrophic failure, sensitive loads and material properties. Also included: Comparative Study of the use of AGMA Geometry Factors and Probabilistic Design Methodology in the Design of Compact Spur Gear Set.

  3. AGRICULTURAL HEALTH STUDY/PESTICIDE EXPOSURE STUDY DESIGN

    EPA Science Inventory

    The Agricultural Health Study (AHS) is a prospective epidemiologic study of a large cohort of pesticide applicators and their spouses in Iowa and North Carolina. The Pesticide Exposure Study is a sub-study to evaluate exposure factors and to provide data to assess exposure cla...

  4. Lessons Learned from Applying Design Thinking in a NASA Rapid Design Study in Aeronautics

    NASA Technical Reports Server (NTRS)

    McGowan, Anna-Maria; Bakula, Casey; Castner, Raymond

    2017-01-01

    In late 2015, NASA's Aeronautics Research Mission Directorate (ARMD) funded an experiment in rapid design and rapid teaming to explore new approaches to solving challenging design problems in aeronautics in an effort to cultivate and foster innovation. This report summarizes several lessons learned from the rapid design portion of the study. This effort entailed learning and applying design thinking, a human-centered design approach, to complete the conceptual design for an open-ended design challenge within six months. The design challenge focused on creating a capability to advance experimental testing of autonomous aeronautics systems, an area of great interest to NASA, the US government as a whole, and an entire ecosystem of users and developers around the globe. A team of nine civil servant researchers from three of NASA's aeronautics field centers with backgrounds in several disciplines was assembled and rapidly trained in design thinking under the guidance of the innovation and design firm IDEO. The design thinking process, while used extensively outside the aerospace industry, is less common and even counter to many practices within the aerospace industry. In this report, several contrasts between common aerospace research and development practices and design thinking are discussed, drawing upon the lessons learned from the NASA rapid design study. The lessons discussed included working towards a design solution without a set of detailed design requirements, which may not be practical or even feasible for management to ascertain for complex, challenging problems. This approach allowed for the possibility of redesigning the original problem statement to better meet the needs of the users. Another lesson learned was to approach problems holistically from the perspective of the needs of individuals that may be affected by advances in topic area instead of purely from a technological feasibility viewpoint. The interdisciplinary nature of the design team also

  5. Design and analysis study of a spacecraft optical transceiver package

    NASA Technical Reports Server (NTRS)

    Lambert, S. G.

    1985-01-01

    A detailed system level design of an Optical Transceiver Package (OPTRANSPAC) for a deep space vehicle whose mission is outer planet exploration is developed. In addition to the terminal design, this study provides estimates of the dynamic environments to be encountered by the transceiver throughout its mission life. Optical communication link analysis, optical thin lens design, electronic functional design and mechanical layout and packaging are employed in the terminal design. Results of the study describe an Optical Transceiver Package capable of communicating to an Earth Orbiting Relay Station at a distance of 10 Astronomical Units (AU) and data rates up to 100 KBPS. The transceiver is also capable of receiving 1 KBPS of command data from the Earth Relay. The physical dimensions of the terminal are contained within a 3.5' x 1.5' x 2.0' envelope and the transceiver weight and power are estimated at 52.2 Kg (115 pounds) and 57 watts, respectively.

  6. Supersonic civil airplane study and design: Performance and sonic boom

    NASA Technical Reports Server (NTRS)

    Cheung, Samson

    1995-01-01

    Since aircraft configuration plays an important role in aerodynamic performance and sonic boom shape, the configuration of the next generation supersonic civil transport has to be tailored to meet high aerodynamic performance and low sonic boom requirements. Computational fluid dynamics (CFD) can be used to design airplanes to meet these dual objectives. The work and results in this report are used to support NASA's High Speed Research Program (HSRP). CFD tools and techniques have been developed for general usages of sonic boom propagation study and aerodynamic design. Parallel to the research effort on sonic boom extrapolation, CFD flow solvers have been coupled with a numeric optimization tool to form a design package for aircraft configuration. This CFD optimization package has been applied to configuration design on a low-boom concept and an oblique all-wing concept. A nonlinear unconstrained optimizer for Parallel Virtual Machine has been developed for aerodynamic design and study.

  7. Initial trade and design studies for the fusion engineering device

    SciTech Connect

    Flanagan, C.A.; Steiner, D.; Smith, G.E.

    1981-06-01

    The Magnetic Fusion Energy Engineering Act of 1980 calls for the operation of a Fusion Engineering Device (FED) by 1990. It is the intent of the Act that the FED, in combination with other testing facilities, will establish the engineering feasibility of magnetic fusion energy. The Fusion Engineering Design Center (FEDC), under the guidance of a Technical Management Board (TMB), initiated a program of trade and design studies in October 1980 to support the selection of the FED concept. This document presents the results of these initial trade and design studies. Based on these results, a baseline configuration has been identified and the Design Center effort for the remainder of the fiscal year will be devoted to the development of a self-consistent FED design description.

  8. Scenario for concurrent conceptual assembly line design: A case study

    NASA Astrophysics Data System (ADS)

    Mas, F.; Ríos, J.; Menéndez, J. L.

    2012-04-01

    The decision to design and build a new aircraft is preceded by years of research and study. Different disciplines work together throughout the lifecycle to ensure not only a complete functional definition of the product, but also a complete industrialization, a marketing plan, a maintenance plan, etc. This case study focuses on the conceptual design phase. During this phase, the design solutions that will meet the functional and industrial requirements are defined, i.e.: the basic requirements of industrialization. During this phase, several alternatives are studied, and the most attractive in terms of performance and cost requirements is selected. As a result of the study of these alternatives, it is possible to define an early conceptual design of the assembly line and its basic parameters. The plant needs, long cycle jigs & tools or industrial means and human resources with the necessary skills can be determined in advance.

  9. New Office Technology: A Study on Curriculum Design.

    ERIC Educational Resources Information Center

    Mulder, Martin

    1989-01-01

    A study collected information about office automation trends, office personnel job profiles, and existing curricula. A curriculum conference was held to design and validate a modular curriculum for office automation. (SK)

  10. Preliminary design study of advanced multistage axial flow core compressors

    NASA Technical Reports Server (NTRS)

    Wisler, D. C.; Koch, C. C.; Smith, L. H., Jr.

    1977-01-01

    A preliminary design study was conducted to identify an advanced core compressor for use in new high-bypass-ratio turbofan engines to be introduced into commercial service in the 1980's. An evaluation of anticipated compressor and related component 1985 state-of-the-art technology was conducted. A parametric screening study covering a large number of compressor designs was conducted to determine the influence of the major compressor design features on efficiency, weight, cost, blade life, aircraft direct operating cost, and fuel usage. The trends observed in the parametric screening study were used to develop three high-efficiency, high-economic-payoff compressor designs. These three compressors were studied in greater detail to better evaluate their aerodynamic and mechanical feasibility.

  11. Conceptual design study for a teleoperator visual system, phase 1

    NASA Technical Reports Server (NTRS)

    Adams, D.; Grant, C.; Johnson, C.; Meirick, R.; Polhemus, C.; Ray, A.; Rittenhouse, D.; Skidmore, R.

    1972-01-01

    Results are reported for work performed during the first phase of the conceptual design study for a teleoperator visual system. This phase consists of four tasks: General requirements, concept development, subsystem requirements and analysis, and concept evaluation.

  12. Structural Design Feasibility Study for the Global Climate Experiment

    SciTech Connect

    Lewin,K.F.; Nagy, J.

    2008-12-01

    Neon, Inc. is proposing to establish a Global Change Experiment (GCE) Facility to increase our understanding of how ecological systems differ in their vulnerability to changes in climate and other relevant global change drivers, as well as provide the mechanistic basis for forecasting ecological change in the future. The experimental design was initially envisioned to consist of two complementary components; (A) a multi-factor experiment manipulating CO{sub 2}, temperature and water availability and (B) a water balance experiment. As the design analysis and cost estimates progressed, it became clear that (1) the technical difficulties of obtaining tight temperature control and maintaining elevated atmospheric carbon dioxide levels within an enclosure were greater than had been expected and (2) the envisioned study would not fit into the expected budget envelope if this was done in a partially or completely enclosed structure. After discussions between NEON management, the GCE science team, and Keith Lewin, NEON, Inc. requested Keith Lewin to expand the scope of this design study to include open-field exposure systems. In order to develop the GCE design to the point where it can be presented within a proposal for funding, a feasibility study of climate manipulation structures must be conducted to determine design approaches and rough cost estimates, and to identify advantages and disadvantages of these approaches including the associated experimental artifacts. NEON, Inc requested this design study in order to develop concepts for the climate manipulation structures to support the NEON Global Climate Experiment. This study summarizes the design concepts considered for constructing and operating the GCE Facility and their associated construction, maintenance and operations costs. Comparisons and comments about experimental artifacts, construction challenges and operational uncertainties are provided to assist in selecting the final facility design. The overall goal

  13. Block 2 SRM conceptual design studies. Volume 1, Book 1: Conceptual design package

    NASA Technical Reports Server (NTRS)

    Smith, Brad; Williams, Neal; Miller, John; Ralston, Joe; Richardson, Jennifer; Moore, Walt; Doll, Dan; Maughan, Jeff; Hayes, Fred

    1986-01-01

    The conceptual design studies of a Block 2 Solid Rocket Motor (SRM) require the elimination of asbestos-filled insulation and was open to alternate designs, such as case changes, different propellants, modified burn rate - to improve reliability and performance. Limitations were placed on SRM changes such that the outside geometry should not impact the physical interfaces with other Space Shuttle elements and should have minimum changes to the aerodynamic and dynamic characteristics of the Space Shuttle vehicle. Previous Space Shuttle SRM experience was assessed and new design concepts combined to define a valid approach to assured flight success and economic operation of the STS. Trade studies, preliminary designs, analyses, plans, and cost estimates are documented.

  14. Child Development and Social Studies Curriculum Design: Toward a Rationale.

    ERIC Educational Resources Information Center

    Knox, Gary A.

    This paper is a working draft of a study which has examined the accumulated research on child growth and development. The draft is designed as an input paper to enable the Marin Social Studies Project to refine its rationale and criteria for a recommended K-12 social studies program of curriculum options. Identification of the capabilities of…

  15. Preliminary 2D design study for A&PCT

    SciTech Connect

    Keto, E.; Azevedo, S.; Roberson, P.

    1995-03-01

    Lawrence Livermore National Laboratory is currently designing and constructing a tomographic scanner to obtain the most accurate possible assays of radioactivity in barrels of nuclear waste in a limited amount of time. This study demonstrates a method to explore different designs using laboratory experiments and numerical simulations. In particular, we examine the trade-off between spatial resolution and signal-to-noise. The simulations are conducted in two dimensions as a preliminary study for three dimensional imaging. We find that the optimal design is entirely dependent on the expected source sizes and activities. For nuclear waste barrels, preliminary results indicate that collimators with widths of 1 to 3 inch and aspect ratios of 5:1 to 10:1 should perform well. This type of study will be repeated in 3D in more detail to optimize the final design.

  16. Vestibular Function Research (VFR) experiment. Phase B: Design definition study

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The Vestibular Functions Research (VFR) Experiment was established to investigate the neurosensory and related physiological processes believed to be associated with the space flight nausea syndrome and to develop logical means for its prediction, prevention and treatment. The VFR Project consists of ground and spaceflight experimentation using frogs as specimens. The phase B Preliminary Design Study provided for the preliminary design of the experiment hardware, preparation of performance and hardware specification and a Phase C/D development plan, establishment of STS (Space Transportation System) interfaces and mission operations, and the study of a variety of hardware, experiment and mission options. The study consist of three major tasks: (1) mission mode trade-off; (2) conceptual design; and (3) preliminary design.

  17. Conceptual design study of 1985 commercial tilt rotor transports. Volume 1: VTOL design summary

    NASA Technical Reports Server (NTRS)

    Detore, J. A.; Sambell, K. W.

    1975-01-01

    Aircraft were synthesized in the 21-, 45-, and 100- passenger categories. Technological factors were considered and the 45-passenger point design, designated the D312, was selected. Variants of the D312 having sideline noise levels in hover of + or - 5 PNdB were also studied. All three 45-passenger aircraft were analyzed for performance, weights, economics, handling qualities, noise footprints, aeroelastic stability and ride comfort. Results are presented.

  18. Designing occupancy studies: general advice and allocating survey effort

    USGS Publications Warehouse

    MacKenzie, D.I.; Royle, J. Andrew

    2005-01-01

    1. The fraction of sampling units in a landscape where a target species is present (occupancy) is an extensively used concept in ecology. Yet in many applications the species will not always be detected in a sampling unit even when present, resulting in biased estimates of occupancy. Given that sampling units are surveyed repeatedly within a relatively short timeframe, a number of similar methods have now been developed to provide unbiased occupancy estimates. However, practical guidance on the efficient design of occupancy studies has been lacking. 2. In this paper we comment on a number of general issues related to designing occupancy studies, including the need for clear objectives that are explicitly linked to science or management, selection of sampling units, timing of repeat surveys and allocation of survey effort. Advice on the number of repeat surveys per sampling unit is considered in terms of the variance of the occupancy estimator, for three possible study designs. 3. We recommend that sampling units should be surveyed a minimum of three times when detection probability is high (> 0.5 survey-1), unless a removal design is used. 4. We found that an optimal removal design will generally be the most efficient, but we suggest it may be less robust to assumption violations than a standard design. 5. Our results suggest that for a rare species it is more efficient to survey more sampling units less intensively, while for a common species fewer sampling units should be surveyed more intensively. 6. Synthesis and applications. Reliable inferences can only result from quality data. To make the best use of logistical resources, study objectives must be clearly defined; sampling units must be selected, and repeated surveys timed appropriately; and a sufficient number of repeated surveys must be conducted. Failure to do so may compromise the integrity of the study. The guidance given here on study design issues is particularly applicable to studies of species

  19. Design vs. Content: A Study of Adolescent Girls' Website Design Preferences

    ERIC Educational Resources Information Center

    Agosto, Denise E.

    2004-01-01

    This study considered the utility of gender schema theory in examining girls' website design preferences. It built on a previous study which identified eight website evaluation criteria related to biological sex: collaboration, social connectivity, flexibility, motility, contextuality, personal identification, inclusion, and graphic/multimedia…

  20. Blade system design studies volume II : preliminary blade designs and recommended test matrix.

    SciTech Connect

    Griffin, Dayton A.

    2004-06-01

    As part of the U.S. Department of Energy's Wind Partnerships for Advanced Component Technologies (WindPACT) program, Global Energy Concepts, LLC is performing a Blade System Design Study (BSDS) concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. The BSDS Volume I project report addresses issues and constraints identified to scaling conventional blade designs to the megawatt size range, and evaluated candidate materials, manufacturing and design innovations for overcoming and improving large blade economics. The current report (Volume II), presents additional discussion of materials and manufacturing issues for large blades, including a summary of current trends in commercial blade manufacturing. Specifications are then developed to guide the preliminary design of MW-scale blades. Using preliminary design calculations for a 3.0 MW blade, parametric analyses are performed to quantify the potential benefits in stiffness and decreased gravity loading by replacement of a baseline fiberglass spar with carbon-fiberglass hybrid material. Complete preliminary designs are then presented for 3.0 MW and 5.0 MW blades that incorporate fiberglass-to-carbon transitions at mid-span. Based on analysis of these designs, technical issues are identified and discussed. Finally, recommendations are made for composites testing under Part I1 of the BSDS, and the initial planned test matrix for that program is presented.

  1. Acting like a physicist: Student approach study to experimental design

    NASA Astrophysics Data System (ADS)

    Karelina, Anna; Etkina, Eugenia

    2007-12-01

    National studies of science education have unanimously concluded that preparing our students for the demands of the 21st century workplace is one of the major goals. This paper describes a study of student activities in introductory college physics labs, which were designed to help students acquire abilities that are valuable in the workplace. In these labs [called Investigative Science Learning Environment (ISLE) labs], students design their own experiments. Our previous studies have shown that students in these labs acquire scientific abilities such as the ability to design an experiment to solve a problem, the ability to collect and analyze data, the ability to evaluate assumptions and uncertainties, and the ability to communicate. These studies mostly concentrated on analyzing students’ writing, evaluated by specially designed scientific ability rubrics. Recently, we started to study whether the ISLE labs make students not only write like scientists but also engage in discussions and act like scientists while doing the labs. For example, do students plan an experiment, validate assumptions, evaluate results, and revise the experiment if necessary? A brief report of some of our findings that came from monitoring students’ activity during ISLE and nondesign labs was presented in the Physics Education Research Conference Proceedings. We found differences in student behavior and discussions that indicated that ISLE labs do in fact encourage a scientistlike approach to experimental design and promote high-quality discussions. This paper presents a full description of the study.

  2. Energy efficient engine: Preliminary design and integration studies

    NASA Technical Reports Server (NTRS)

    Johnston, R. P.; Hirschkron, R.; Koch, C. C.; Neitzel, R. E.; Vinson, P. W.

    1978-01-01

    Parametric design and mission evaluations of advanced turbofan configurations were conducted for future transport aircraft application. Economics, environmental suitability and fuel efficiency were investigated and compared with goals set by NASA. Of the candidate engines which included mixed- and separate-flow, direct-drive and geared configurations, an advanced mixed-flow direct-drive configuration was selected for further design and evaluation. All goals were judged to have been met except the acoustic goal. Also conducted was a performance risk analysis and a preliminary aerodynamic design of the 10 stage 23:1 pressure ratio compressor used in the study engines.

  3. Computer-aided space shuttle orbiter wing design study

    NASA Technical Reports Server (NTRS)

    Phillips, W. P.; Decker, J. P.; Rau, T. R.; Glatt, C. R.

    1974-01-01

    An analytical and experimental investigation has been made to provide a space shuttle orbiter wing design that met the guideline requirements of landing performance, stability, and hypersonic trim for a specified center-of-gravity envelope. The analytical study was facilitated by the use of the Optimal Design Integration system (ODIN) and the experimental part of the investigation was conducted in the Langley low-turbulence pressure tunnel and the Langley continuous-flow hypersonic tunnel.

  4. Design Study for a Low-Distortion Holographic HUD.

    DTIC Science & Technology

    1982-01-01

    HUD W.S. Colburn, R.C. Fairchild RADAR AND OPTICS DIVISION ENVIRONMENTAL RESEARCH INSTITUTE OF MICHIGAN P.O. Box 8618, Ann Arbor, Michigan 48107...When Data Entered) l "Diffraction Optics Design Study" FOREWORD This report was prepared by the Electro-Optics Depart- ment, Radar and Optics...where the ray directions are reversed by the raytrace program. This design resulted in a combiner with a focal length of 193 mm, and which is predicted

  5. Collaborative Study of Children Treated for Phenylketonuria: Study Design

    ERIC Educational Resources Information Center

    Williamson, Malcolm; And Others

    1977-01-01

    Available from: Arthur Retlaw and Associates, Inc., Suite 2080, 1603 Orrington Avenue, Evanston, Illinois 60201. Described is a study in which a large sample of children (n=444) with phenylketonuria (an inborn metabolic error usually related to impaired cognitive ability) were treated under controlled conditions from near birth to 6 years of age.…

  6. The Potential of Adaptive Design in Animal Studies.

    PubMed

    Majid, Arshad; Bae, Ok-Nam; Redgrave, Jessica; Teare, Dawn; Ali, Ali; Zemke, Daniel

    2015-10-12

    Clinical trials are the backbone of medical research, and are often the last step in the development of new therapies for use in patients. Prior to human testing, however, preclinical studies using animal subjects are usually performed in order to provide initial data on the safety and effectiveness of prospective treatments. These studies can be costly and time consuming, and may also raise concerns about the ethical treatment of animals when potentially harmful procedures are involved. Adaptive design is a process by which the methods used in a study may be altered while it is being conducted in response to preliminary data or other new information. Adaptive design has been shown to be useful in reducing the time and costs associated with clinical trials, and may provide similar benefits in preclinical animal studies. The purpose of this review is to summarize various aspects of adaptive design and evaluate its potential for use in preclinical research.

  7. 5 MW pulsed spallation neutron source, Preconceptual design study

    SciTech Connect

    Not Available

    1994-06-01

    This report describes a self-consistent base line design for a 5 MW Pulsed Spallation Neutron Source (PSNS). It is intended to establish feasibility of design and as a basis for further expanded and detailed studies. It may also serve as a basis for establishing project cost (30% accuracy) in order to intercompare competing designs for a PSNS not only on the basis of technical feasibility and technical merit but also on the basis of projected total cost. The accelerator design considered here is based on the objective of a pulsed neutron source obtained by means of a pulsed proton beam with average beam power of 5 MW, in {approx} 1 {mu}sec pulses, operating at a repetition rate of 60 Hz. Two target stations are incorporated in the basic facility: one for operation at 10 Hz for long-wavelength instruments, and one operating at 50 Hz for instruments utilizing thermal neutrons. The design approach for the proton accelerator is to use a low energy linear accelerator (at 0.6 GeV), operating at 60 Hz, in tandem with two fast cycling booster synchrotrons (at 3.6 GeV), operating at 30 Hz. It is assumed here that considerations of cost and overall system reliability may favor the present design approach over the alternative approach pursued elsewhere, whereby use is made of a high energy linear accelerator in conjunction with a dc accumulation ring. With the knowledge that this alternative design is under active development, it was deliberately decided to favor here the low energy linac-fast cycling booster approach. Clearly, the present design, as developed here, must be carried to the full conceptual design stage in order to facilitate a meaningful technology and cost comparison with alternative designs.

  8. Computing requirements for S. S. C. accelerator design and studies

    SciTech Connect

    Dragt, A.; Talman, R.; Siemann, R.; Dell, G.F.; Leemann, B.; Leemann, C.; Nauenberg, U.; Peggs, S.; Douglas, D.

    1984-01-01

    We estimate the computational hardware resources that will be required for accelerator physics studies during the design of the Superconducting SuperCollider. It is found that both Class IV and Class VI facilities (1) will be necessary. We describe a user environment for these facilities that is desirable within the context of accelerator studies. An acquisition scenario for these facilities is presented.

  9. Experiences of Computer Science Curriculum Design: A Phenomenological Study

    ERIC Educational Resources Information Center

    Sloan, Arthur; Bowe, Brian

    2015-01-01

    This paper presents a qualitative study of 12 computer science lecturers' experiences of curriculum design of several degree programmes during a time of transition from year-long to semesterised courses, due to institutional policy change. The background to the study is outlined, as are the reasons for choosing the research methodology. The main…

  10. Integrated source and channel encoded digital communication system design study

    NASA Technical Reports Server (NTRS)

    Huth, G. K.; Udalov, S.

    1974-01-01

    This study investigated the configuration and integration of a wideband communication system with a Ku-band rendezvous radar system. The goal of the study was to provide as much commonality between the two systems as possible. The antenna design was described with the only change being the requirement for dual polarization (linear for the radar system and circular for the communication system).

  11. A Study of Assessments Designed for Student Success

    ERIC Educational Resources Information Center

    Delepine, Sidney G., III

    2012-01-01

    The purpose of this quantitative study is to compare a new assessment tool, the SkillsUSA Connect Assessment with the NOCTI assessment to determine which test results in more students achieving success. A quantitative study, designed to compare test scores of students taking the NOCTI assessment and new assessments from SkillsUSA, called the…

  12. Aerodynamic Design Study of an Advanced Active Twist Rotor

    NASA Technical Reports Server (NTRS)

    Sekula, Martin K.; Wilbur, Matthew L.; Yeager, William T., Jr.

    2003-01-01

    An Advanced Active Twist Rotor (AATR) is currently being developed by the U.S. Army Vehicle Technology Directorate at NASA Langley Research Center. As a part of this effort, an analytical study was conducted to determine the impact of blade geometry on active-twist performance and, based on those findings, propose a candidate aerodynamic design for the AATR. The process began by creating a baseline design which combined the dynamic design of the original Active Twist Rotor and the aerodynamic design of a high lift rotor concept. The baseline model was used to conduct a series of parametric studies to examine the effect of linear blade twist and blade tip sweep, droop, and taper on active-twist performance. Rotor power requirements and hub vibration were also examined at flight conditions ranging from hover to advance ratio = 0.40. A total of 108 candidate designs were analyzed using the second-generation version of the Comprehensive Analytical Model of Rotorcraft Aerodynamics and Dynamics (CAMRAD II) code. The study concluded that the vibration reduction capabilities of a rotor utilizing controlled, strain-induced twisting are enhanced through the incorporation of blade tip sweep, droop, and taper into the blade design, while they are degraded by increasing the nose-down linear blade twist. Based on the analysis of rotor power, hub vibration, and active-twist response, a candidate aerodynamic design for the AATR consisting of a blade with approximately 10 degrees of linear blade twist and a blade tip design with 30 degree sweep, 10 degree droop, and 2.5:1 taper ratio over the outer five percent of the blade is proposed.

  13. The healthy men study: design and recruitment considerations for environmental epidemiologic studies in male reproductive health

    EPA Science Inventory

    Study Objective: To describe study conduct and response and participant characteristics. Design: Prospective cohort study. Setting: Participants were male partners of women enrolled in a community-based study of drinking water disinfection by-products and pregnancy healt...

  14. Design studies for twist-coupled wind turbine blades.

    SciTech Connect

    Valencia, Ulyses; Locke, James

    2004-06-01

    This study presents results obtained for four hybrid designs of the Northern Power Systems (NPS) 9.2-meter prototype version of the ERS-100 wind turbine rotor blade. The ERS-100 wind turbine rotor blade was designed and developed by TPI composites. The baseline design uses e-glass unidirectional fibers in combination with {+-}45-degree and random mat layers for the skin and spar cap. This project involves developing structural finite element models of the baseline design and carbon hybrid designs with and without twist-bend coupling. All designs were evaluated for a unit load condition and two extreme wind conditions. The unit load condition was used to evaluate the static deflection, twist and twist-coupling parameter. Maximum deflections and strains were determined for the extreme wind conditions. Linear and nonlinear buckling loads were determined for a tip load condition. The results indicate that carbon fibers can be used to produce twist-coupled designs with comparable deflections, strains and buckling loads to the e-glass baseline.

  15. Juvenile animal toxicity study designs to support pediatric drug development.

    PubMed

    Cappon, Gregg D; Bailey, Graham P; Buschmann, Jochen; Feuston, Maureen H; Fisher, J Edward; Hew, Kok Wah; Hoberman, Alan M; Ooshima, Yojiro; Stump, Donald G; Hurtt, Mark E

    2009-12-01

    The objective of juvenile animal toxicity studies of pharmaceuticals is to obtain safety data, including information on the potential for adverse effects on postnatal growth and development. Studies in juvenile animals may assist in identifying postnatal developmental toxicities or other adverse effects that are not adequately assessed in the routine toxicity evaluations and that cannot be safely or adequately measured in pediatric clinical trials. Unlike the traditional reproductive and developmental toxicology studies that have been discussed in the accompanying reports, the design requirements for toxicity studies in juvenile animals are not explicitly defined in regulatory guidance. However, studies in juvenile animals can be useful in providing safety information necessary to enable pediatric clinical trials in pediatric patients or when there are special concerns for toxicities that cannot be safely or adequately measured in clinical trials. These juvenile animal toxicity studies are designed on a case-by-case basis. General design considerations and examples of study designs for assessment of juvenile animal toxicity are discussed.

  16. Integrated source and channel encoded digital communication system design study

    NASA Technical Reports Server (NTRS)

    Alem, W. K.; Huth, G. K.; Simon, M. K.

    1978-01-01

    The particular Ku-band carrier, PN despreading, and symbol synchronization strategies, which were selected for implementation in the Ku-band transponder aboard the orbiter, were assessed and evaluated from a systems performance viewpoint, verifying that system specifications were met. A study was performed of the design and implementation of tracking techniques which are suitable for incorporation into the Orbiter Ku-band communication system. Emphasis was placed on maximizing tracking accuracy and communication system flexibility while minimizing cost, weight, and system complexity of Orbiter and ground systems hardware. The payload communication study assessed the design and performance of the forward link and return link bent-pipe relay modes for attached and detached payloads. As part of this study, a design for a forward link bent-pipe was proposed which employs a residual carrier but which is tracked by the existing Costas loop.

  17. Preliminary design study of the TMT Telescope structure system: overview

    NASA Astrophysics Data System (ADS)

    Usuda, Tomonori; Ezaki, Yutaka; Kawaguchi, Noboru; Nagae, Kazuhiro; Kato, Atsushi; Takaki, Junji; Hirano, Masaki; Hattori, Tomoya; Tabata, Masaki; Horiuchi, Yasushi; Saruta, Yusuke; Sofuku, Satoru; Itoh, Noboru; Oshima, Takeharu; Takanezawa, Takashi; Endo, Makoto; Inatani, Junji; Iye, Masanori; Sadjadpour, Amir; Sirota, Mark; Roberts, Scott; Stepp, Larry

    2014-07-01

    We present an overview of the preliminary design of the Telescope Structure System (STR) of Thirty Meter Telescope (TMT). NAOJ was given responsibility for the TMT STR in early 2012 and engaged Mitsubishi Electric Corporation (MELCO) to take over the preliminary design work. MELCO performed a comprehensive preliminary design study in 2012 and 2013 and the design successfully passed its Preliminary Design Review (PDR) in November 2013 and April 2014. Design optimizations were pursued to better meet the design requirements and improvements were made in the designs of many of the telescope subsystems as follows: 1. 6-legged Top End configuration to support secondary mirror (M2) in order to reduce deformation of the Top End and to keep the same 4% blockage of the full aperture as the previous STR design. 2. "Double Lower Tube" of the elevation (EL) structure to reduce the required stroke of the primary mirror (M1) actuators to compensate the primary mirror cell (M1 Cell) deformation caused during the EL angle change in accordance with the requirements. 3. M1 Segment Handling System (SHS) to be able to make removing and installing 10 Mirror Segment Assemblies per day safely and with ease over M1 area where access of personnel is extremely difficult. This requires semi-automatic sequence operation and a robotic Segment Lifting Fixture (SLF) designed based on the Compliance Control System, developed for controlling industrial robots, with a mechanism to enable precise control within the six degrees of freedom of position control. 4. CO2 snow cleaning system to clean M1 every few weeks that is similar to the mechanical system that has been used at Subaru Telescope. 5. Seismic isolation and restraint systems with respect to safety; the maximum acceleration allowed for M1, M2, tertiary mirror (M3), LGSF, and science instruments in 1,000 year return period earthquakes are defined in the requirements. The Seismic requirements apply to any EL angle, regardless of the

  18. High performance APCS conceptual design and evaluation scoping study

    SciTech Connect

    Soelberg, N.; Liekhus, K.; Chambers, A.; Anderson, G.

    1998-02-01

    This Air Pollution Control System (APCS) Conceptual Design and Evaluation study was conducted to evaluate a high-performance (APC) system for minimizing air emissions from mixed waste thermal treatment systems. Seven variations of high-performance APCS designs were conceptualized using several design objectives. One of the system designs was selected for detailed process simulation using ASPEN PLUS to determine material and energy balances and evaluate performance. Installed system capital costs were also estimated. Sensitivity studies were conducted to evaluate the incremental cost and benefit of added carbon adsorber beds for mercury control, specific catalytic reduction for NO{sub x} control, and offgas retention tanks for holding the offgas until sample analysis is conducted to verify that the offgas meets emission limits. Results show that the high-performance dry-wet APCS can easily meet all expected emission limits except for possibly mercury. The capability to achieve high levels of mercury control (potentially necessary for thermally treating some DOE mixed streams) could not be validated using current performance data for mercury control technologies. The engineering approach and ASPEN PLUS modeling tool developed and used in this study identified APC equipment and system performance, size, cost, and other issues that are not yet resolved. These issues need to be addressed in feasibility studies and conceptual designs for new facilities or for determining how to modify existing facilities to meet expected emission limits. The ASPEN PLUS process simulation with current and refined input assumptions and calculations can be used to provide system performance information for decision-making, identifying best options, estimating costs, reducing the potential for emission violations, providing information needed for waste flow analysis, incorporating new APCS technologies in existing designs, or performing facility design and permitting activities.

  19. Design Study Of Cyclotron Magnet With Permanent Magnet

    SciTech Connect

    Kim, Hyun Wook; Chai, Jong Seo

    2011-06-01

    Low energy cyclotrons for Positron emission tomography (PET) have been wanted for the production of radio-isotopes after 2002. In the low energy cyclotron magnet design, increase of magnetic field between the poles is needed to make a smaller size of magnet and decrease power consumption. The Permanent magnet can support this work without additional electric power consumption in the cyclotron. In this paper the study of cyclotron magnet design using permanent magnet is shown and also the comparison between normal magnet and the magnet which is designed with permanent magnet is shown. Maximum energy of proton is 8 MeV and RF frequency is 79.3 MHz. 3D CAD design was done by CATIA P3 V5 R18 and the All field calculations had been performed by OPERA-3D TOSCA. The self-made beam dynamics program OPTICY is used for making isochronous field and other calculations.

  20. Design of an adiabatic demagnetization refrigerator for studies in astrophysics

    NASA Technical Reports Server (NTRS)

    Castles, S.

    1983-01-01

    An adiabatic demagnetization refrigerator was designed for cooling infrared bolometers for studies in astrophysics and aeronomy. The design was tailored to the requirements of a Shuttle sortie experiment. The refrigerator should be capable of maintaining three bolometers at 0.1 K with a 90% cycle. The advantage are of operations the bolometer at 0.1K. greater sensitivity, faster response time, and the ability to use larger bolometer elements without compromising the response time. The design presented is the first complete design of an ADR intended for use in space. The most important of these specifications are to survive a Shuttle launch, to operate with 1.5 K - 2.0 K space-pumped liquid helium as a heat sink, to have a 90% duty cycle, and to be highly efficient.

  1. Design Study Of Cyclotron Magnet With Permanent Magnet

    NASA Astrophysics Data System (ADS)

    Kim, Hyun Wook; Chai, Jong Seo

    2011-06-01

    Low energy cyclotrons for Positron emission tomography (PET) have been wanted for the production of radio-isotopes after 2002. In the low energy cyclotron magnet design, increase of magnetic field between the poles is needed to make a smaller size of magnet and decrease power consumption. The Permanent magnet can support this work without additional electric power consumption in the cyclotron. In this paper the study of cyclotron magnet design using permanent magnet is shown and also the comparison between normal magnet and the magnet which is designed with permanent magnet is shown. Maximum energy of proton is 8 MeV and RF frequency is 79.3 MHz. 3D CAD design was done by CATIA P3 V5 R18 [1] and the All field calculations had been performed by OPERA-3D TOSCA [2]. The self-made beam dynamics program OPTICY [3] is used for making isochronous field and other calculations.

  2. AFB/open cycle gas turbine conceptual design study

    NASA Technical Reports Server (NTRS)

    Dickinson, T. W.; Tashjian, R.

    1983-01-01

    Applications of coal fired atmospheric fluidized bed gas turbine systems in industrial cogeneration are identified. Based on site-specific conceptual designs, the potential benefits of the AFB/gas turbine system were compared with an atmospheric fluidized design steam boiler/steam turbine system. The application of these cogeneration systems at four industrial plant sites is reviewed. A performance and benefit analysis was made along with a study of the representativeness of the sites both in regard to their own industry and compared to industry as a whole. A site was selected for the conceptual design, which included detailed site definition, AFB/gas turbine and AFB/steam turbine cogeneration system designs, detailed cost estimates, and comparative performance and benefit analysis. Market and benefit analyses identified the potential market penetration for the cogeneration technologies and quantified the potential benefits.

  3. Gas recombination device design and cost study. Final report

    SciTech Connect

    Not Available

    1980-07-01

    Under a contract with Argonne National Laboratory, VARTA Batterie AG. conducted a design and cost study of hydrogen-oxygen recombination devices (HORD) for use with utility load-leveling lead-acid cells. Design specifications for the devices, through extensive calculation of the heat-flow conditions of the unit, were developed. Catalyst and condenser surface areas were specified. The exact dimensions can, however, be adjusted to the cell dimension and the space available above the cell. Design specifications were also developed for additional components required to ensure proper function of the recombination device, including metal hydride compound decomposer, aerosol retainer, and gas storage component. Costs for HORD were estimated to range from $4 to $10/kWh cell capacity for the production of a large number of units (greater than or equal to 10,000 units). The cost is a function of cell size and positive grid design. 21 figures, 2 tables.

  4. Case study: Lockheed-Georgia Company integrated design process

    NASA Technical Reports Server (NTRS)

    Waldrop, C. T.

    1980-01-01

    A case study of the development of an Integrated Design Process is presented. The approach taken in preparing for the development of an integrated design process includes some of the IPAD approaches such as developing a Design Process Model, cataloging Technical Program Elements (TPE's), and examining data characteristics and interfaces between contiguous TPE's. The implementation plan is based on an incremental development of capabilities over a period of time with each step directed toward, and consistent with, the final architecture of a total integrated system. Because of time schedules and different computer hardware, this system will not be the same as the final IPAD release; however, many IPAD concepts will no doubt prove applicable as the best approach. Full advantage will be taken of the IPAD development experience. A scenario that could be typical for many companies, even outside the aerospace industry, in developing an integrated design process for an IPAD-type environment is represented.

  5. Design.

    ERIC Educational Resources Information Center

    Online-Offline, 1998

    1998-01-01

    Provides an annotated bibliography of resources on this month's theme "Design" for K-8 language arts, art and architecture, music and dance, science, math, social studies, health, and physical education. Includes Web sites, CD-ROMs and software, videos, books, audiotapes, magazines, professional resources and classroom activities.…

  6. Large scale prop-fan structural design study. Volume 2: Preliminary design of SR-7

    NASA Technical Reports Server (NTRS)

    Billman, L. C.; Gruska, C. J.; Ladden, R. M.; Leishman, D. K.; Turnberg, J. E.

    1988-01-01

    In recent years, considerable attention has been directed toward improving aircraft fuel consumption. Studies have shown that the inherent efficiency advantage that turboprop propulsion systems have demonstrated at lower cruise speeds may now be extended to the higher speeds of today's turbofan and turbojet-powered aircraft. To achieve this goal, new propeller designs will require features such as thin, high speed airfoils and aerodynamic sweep, features currently found only in wing designs for high speed aircraft. This is Volume 2 of a 2 volume study to establish structural concepts for such advanced propeller blades, to define their structural properties, to identify any new design, analysis, or fabrication techniques which were required, and to determine the structural tradeoffs involved with several blade shapes selected primarily on the basis of aero/acoustic design considerations. The feasibility of fabricating and testing dynamically scaled models of these blades for aeroelastic testing was also established. The preliminary design of a blade suitable for flight use in a testbed advanced turboprop was conducted and is described.

  7. The cardiac insufficiency talinolol study (CITAS) study design.

    PubMed

    Campeanu, A

    2001-06-01

    Beta-blockers without partial agonist activity are now considered to be strategic therapy for patients with chronic heart failure, but many issues remain to be clarified. The objective of the double-blind, randomized, placebo-controlled cardiac insufficiency talinolol study (CITAS) is to assess efficacy and safety of talinolol - a selective beta-1 adrenoreceptor blocker - in patients with ischemic and non-ischemic heart failure. The primary end-point refers to the influence of talinolol on exercise capacity, evaluated by 6-min walking-test. Secondary end-points consist of left ventricular function, cardiovascular and all-cause mortality, hospitalizations, quality of life, combined clinical end-points and adverse events. There were enrolled 294 patients with stable heart failure in NYHA class II-IV, LVEF <40%, receiving diuretics, ACE-inhibitors and optionally nitrates and digoxin. Talinolol was titrated up to 100 mg/day (one arm) or to 150 mg/d (the other arm), starting with 12.5 mg daily. Enrollment began in November 1997 and the last visit will be in December 2000.

  8. Design Studies of ``100% Pu'' Mox Lead Test Assembly

    SciTech Connect

    Pavlovichev, A.M.

    2001-01-11

    In this document the results of neutronics studies of <<100%Pu>> MOX LTA design are presented. The parametric studies of infinite MOX-UOX grids, MOX-UOX core fragments and of VVER-1000 core with 3 MOX LTAs are performed. The neutronics parameters of MOX fueled core have been performed for the chosen design MOX LTA using the Russian 3D code BIPR-7A and 2D code PERMAK-A with the constants prepared by the cell spectrum code TVS-M.

  9. Aircraft energy efficiency laminar flow control wing design study

    NASA Technical Reports Server (NTRS)

    Bonner, T. F., Jr.; Pride, J. D., Jr.; Fernald, W. W.

    1977-01-01

    An engineering design study was performed in which laminar flow control (LFC) was integrated into the wing of a commercial passenger transport aircraft. A baseline aircraft configuration was selected and the wing geometry was defined. The LFC system, with suction slots, ducting, and suction pumps was integrated with the wing structure. The use of standard aluminum technology and advanced superplastic formed diffusion bonded titanium technology was evaluated. The results of the design study show that the LFC system can be integrated with the wing structure to provide a structurally and aerodynamically efficient wing for a commercial transport aircraft.

  10. Design Core Commonalities: A Study of the College of Design at Iowa State University

    ERIC Educational Resources Information Center

    Venes, Jane

    2015-01-01

    This comprehensive study asks what a group of rather diverse disciplines have in common. It involves a cross-disciplinary examination of an entire college, the College of Design at Iowa State University. This research was intended to provide a sense of direction in developing and assessing possible core content. The reasoning was that material…

  11. On Becoming a Civic-Minded Instructional Designer: An Ethnographic Study of an Instructional Design Experience

    ERIC Educational Resources Information Center

    Yusop, Farrah Dina; Correia, Ana-Paula

    2014-01-01

    This ethnographic study took place in a graduate course at a large research university in the Midwestern United States. It presents an in-depth examination of the experiences and challenges of a group of four students learning to be Instructional Design and Technology professionals who are concerned with the well-being of all members of a society,…

  12. Digital Modeling in Design Foundation Coursework: An Exploratory Study of the Effectiveness of Conceptual Design Software

    ERIC Educational Resources Information Center

    Guidera, Stan; MacPherson, D. Scot

    2008-01-01

    This paper presents the results of a study that was conducted to identify and document student perceptions of the effectiveness of computer modeling software introduced in a design foundations course that had previously utilized only conventional manually-produced representation techniques. Rather than attempt to utilize a production-oriented CAD…

  13. Considerations in Writing About Single-Case Experimental Design Studies.

    PubMed

    Skolasky, Richard L

    2016-12-01

    Single-case experimental design (SCED) studies are particularly useful for examining the processes and outcomes of psychological and behavioral studies. Accurate reporting of SCED studies is critical in explaining the study to the reader and allowing replication. This paper outlines important elements that authors should cover when reporting the results of a SCED study. Authors should provide details on the participant, independent and dependent variables under examination, materials and procedures, and data analysis. Particular emphasis should be placed on justifying the assumptions made and explaining how violations of these assumptions may alter the results of the SCED study.

  14. Partial gravity habitat study: With application to lunar base design

    NASA Technical Reports Server (NTRS)

    Capps, Stephen; Lorandos, Jason; Akhidime, Eval; Bunch, Michael; Lund, Denise; Moore, Nathan; Murakawa, Kio; Bell, Larry; Trotti, Guillermo; Neubek, Deb

    1989-01-01

    Comprehensive design requirements associated with designing habitats for humans in a partial gravity environment were investigated and then applied to a lunar base design. Other potential sites for application include planetary surfaces such as Mars, variable gravity research facilities, or a rotating spacecraft. Design requirements for partial gravity environments include: (1) locomotion changes in less than normal Earth gravity; (2) facility design issues, such as interior configuration, module diameter and geometry; and (3) volumetric requirements based on the previous as well as psychological issues involved in prolonged isolation. For application to a Lunar Base, it was necessary to study the exterior architecture and configuration to insure optimum circulation patterns while providing dual egress. Radiation protection issues were addressed to provide a safe and healthy environment for the crew, and finally, the overall site was studied to locate all associated facilities in context with the habitat. Mission planning was not the purpose of this study; therefore, a Lockheed scenario was used as an outline for the Lunar Base application, which was then modified to meet the project needs.

  15. Conceptual design study of a nuclear Brayton turboalternator-compressor

    NASA Technical Reports Server (NTRS)

    1971-01-01

    A comprehensive analysis and conceptual design study of the turboalternator-compressor components using HeXe as the working fluid was performed. The study was conducted in three phases: general configuration analysis (Phase 1), design variations (Phase 2), and conceptual design study (Phase 3). During the Phase 1 analysis, individual turbine, alternator, compressor, and bearing and seal designs were evaluated. Six turboalternator-compressor (TAC) configurations were completed. Phase 2 consisted of evaluating one selected Phase 1 TAC configuration to calculate its performance when operating under new cycle conditions, namely, one higher and one lower turbine inlet temperature and one case with krypton as the working fluid. Based on the Phase 1 and 2 results, a TAC configuration that incorporated a radial compressor, a radial turbine, a Lundell alternator, and gas bearings was selected. During Phase 3 a new layout of the TAC was prepared that reflects the cycle state points necessary to accommodate a zirconium hydride moderated reactor and a 400 Hz alternator. The final TAC design rotates at 24,000 rpm and produces 160 kWe, 480 V, 3-phase, 400 hertz power.

  16. Utilization of optimal study design for maternal and fetal sheep propofol pharmacokinetics study: a preliminary study.

    PubMed

    Sherwin, Catherine M T; Ngamprasertwong, Pornswan; Sadhasivam, Senthilkumar; Vinks, Alexander A

    2014-02-01

    Multiple blood samples are generally required for measurement of pharmacokinetic (PK) parameters. D-optimal design is a popular and frequently used approach for determination of sampling time points in order to minimize the number of samples, while optimizing the estimation of PK parameters. Optimal design utilizing ADAPT (v5, BSR, University of Southern California, Los Angeles) developed a sparse sampling strategy to determine measurement of propofol in pregnant sheep. Propofal was administered as supplemental anesthetic agent to inhalation anesthesia to mimic anesthesia for open fetal surgery. In our preliminary study, propofol 3 mg/kg was given as a bolus to the ewe, followed by propofol infusion at rate 450 mcg/kg/min for 60 minutes, then decreased to 75 mcg/kg/min for 90 more minutes and then ceased. A three compartment model described the PK parameters with the fetus assumed as the third compartment. Initially, sampling times were chosen from thirteen time points as previously stated in the literature. Using priori propofol PK estimates, the final 9 sample time points were proposed in an optimal design with a change in infusion rate occurring between 65 and 75 minutes and sampling proposed at 5, 15, 25, 65, 75, 100, 110, 150, and 180 minutes. D-optimal design optimized the number and timing of samplings, which led to a reduction of cost and man power in the study protocol while preserving the ability to estimate propofol PK parameters in the maternal and fetal sheep model. Initial evaluation of samples collected from three sheep using the optimal design strategy confirmed the performance of the design in obtaining effective PK parameter estimates.

  17. Design and analysis issues in gene and environment studies.

    PubMed

    Liu, Chen-yu; Maity, Arnab; Lin, Xihong; Wright, Robert O; Christiani, David C

    2012-12-19

    Both nurture (environmental) and nature (genetic factors) play an important role in human disease etiology. Traditionally, these effects have been thought of as independent. This perspective is ill informed for non-mendelian complex disorders which result as an interaction between genetics and environment. To understand health and disease we must study how nature and nurture interact. Recent advances in human genomics and high-throughput biotechnology make it possible to study large numbers of genetic markers and gene products simultaneously to explore their interactions with environment. The purpose of this review is to discuss design and analytic issues for gene-environment interaction studies in the "-omics" era, with a focus on environmental and genetic epidemiological studies. We present an expanded environmental genomic disease paradigm. We discuss several study design issues for gene-environmental interaction studies, including confounding and selection bias, measurement of exposures and genotypes. We discuss statistical issues in studying gene-environment interactions in different study designs, such as choices of statistical models, assumptions regarding biological factors, and power and sample size considerations, especially in genome-wide gene-environment studies. Future research directions are also discussed.

  18. Design and analysis issues in gene and environment studies

    PubMed Central

    2012-01-01

    Both nurture (environmental) and nature (genetic factors) play an important role in human disease etiology. Traditionally, these effects have been thought of as independent. This perspective is ill informed for non-mendelian complex disorders which result as an interaction between genetics and environment. To understand health and disease we must study how nature and nurture interact. Recent advances in human genomics and high-throughput biotechnology make it possible to study large numbers of genetic markers and gene products simultaneously to explore their interactions with environment. The purpose of this review is to discuss design and analytic issues for gene-environment interaction studies in the “-omics” era, with a focus on environmental and genetic epidemiological studies. We present an expanded environmental genomic disease paradigm. We discuss several study design issues for gene-environmental interaction studies, including confounding and selection bias, measurement of exposures and genotypes. We discuss statistical issues in studying gene-environment interactions in different study designs, such as choices of statistical models, assumptions regarding biological factors, and power and sample size considerations, especially in genome-wide gene-environment studies. Future research directions are also discussed. PMID:23253229

  19. [Introduction to critical reading of articles: study design and biases].

    PubMed

    García Villar, C

    2015-01-01

    The critical evaluation of an article enables professionals to make good use of the new information and therefore has direct repercussions for the benefit of our patients. Before undertaking a detailed critical reading of the chosen article, we need to consider whether the study used the most appropriate design for the question it aimed to answer (i.e., whether the level of evidence is adequate). To do this, we need to know how to classify studies in function of their design (descriptive or analytical; prospective or retrospective; cross-sectional or longitudinal) as well as their correlation with the levels of evidence. In critical reading it is also important to know the main systematic errors or biases that can affect a study. Biases can appear in any phase of a study; they can affect the sample, the development of the study, or the measurement of the results.

  20. Influence analysis on crossover design experiment in bioequivalence studies.

    PubMed

    Huang, Yufen; Ke, Bo-Shiang

    2014-01-01

    Crossover designs are commonly used in bioequivalence studies. However, the results can be affected by some outlying observations, which may lead to the wrong decision on bioequivalence. Therefore, it is essential to investigate the influence of aberrant observations. Chow and Tse in 1990 discussed this issue by considering the methods based on the likelihood distance and estimates distance. Perturbation theory provides a useful tool for the sensitivity analysis on statistical models. Hence, in this paper, we develop the influence functions via the perturbation scheme proposed by Hampel as an alternative approach on the influence analysis for a crossover design experiment. Moreover, the comparisons between the proposed approach and the method proposed by Chow and Tse are investigated. Two real data examples are provided to illustrate the results of these approaches. Our proposed influence functions show excellent performance on the identification of outlier/influential observations and are suitable for use with small sample size crossover designs commonly used in bioequivalence studies.

  1. Design study of the KIRAMS-430 superconducting cyclotron magnet

    NASA Astrophysics Data System (ADS)

    Kim, Hyun Wook; Kang, Joonsun; Hong, Bong Hwan; Jung, In Su

    2016-07-01

    Design study of superconducting cyclotron magnet for the carbon therapy was performed at the Korea Institute of Radiological and Medical Science (KIRAMS). The name of this project is The Korea Heavy Ion Medical Accelerator (KHIMA) project and a fixed frequency cyclotron with four spiral sector magnet was one of the candidate for the accelerator type. Basic parameters of the cyclotron magnet and its characteristics were studied. The isochronous magnetic field which can guide the 12C6+ ions up to 430 MeV/u was designed and used for the single particle tracking simulation. The isochronous condition of magnetic field was achieved by optimization of sector gap and width along the radius. Operating range of superconducting coil current was calculated and changing of the magnetic field caused by mechanical deformations of yokes was considered. From the result of magnetic field design, structure of the magnet yoke was planned.

  2. The case-crossover study design in pharmacoepidemiology.

    PubMed

    Delaney, Joseph A 'Chris'; Suissa, Samy

    2009-02-01

    In the study of the association of transient drug exposures with acute outcomes, the case-crossover design is an efficient alternative to the case-control approach. This design based exclusively on the case series uses within-subject comparisons of drug exposures over time to estimate the rate ratio of the outcome associated with the drug under study. This design inherently removes the biasing effects of unmeasured, time-invariant confounding factors from the estimated rate ratio, but is sensitive to several assumptions. We illustrated the case-crossover design and explored its sensitivity using data from 4028 cases of gastrointestinal bleeding from the General Practice Research Database in assessing the effects of the drug warfarin. We compared the use of different time window lengths to assess exposure and considered the use of a case-time-control design to account for exposure time trends. The case-crossover approach found no excess risk of bleeding with warfarin exposure [rate ratio 0.98; 95% confidence interval (CI): 0.74-1.28] using a 1-month time window. When we restricted the analysis to subjects with truly transient drug exposure, defined by 1 to 3 prescriptions in the previous year, the rate ratio was 2.59 (95% CI: 1.42-4.74). To consider the longer 1-year exposure time window, the case-time-control approach was used and resulted in a rate ratio of 1.72 (95% CI: 1.08-2.43). In conclusion, the case-crossover design is potentially a powerful approach to assess the risk of drugs. This design is, however, highly sensitive to assumptions about intermittency of drug use and the length of the exposure time window, as demonstrated with the example of bleeding associated with warfarin use.

  3. Optimal Design for Regression Discontinuity Studies with Clustering

    ERIC Educational Resources Information Center

    Rhoads, Christopher; Dye, Charles

    2014-01-01

    Recent years have seen an increased interest in quantitative educational research studies that use random assignment (RA) to evaluate the causal impacts of educational interventions (Angrist, 2004). The multi-level structure of the public education system in the United States often leads to experimental designs where naturally occurring clusters…

  4. Designing Intervention Studies: Selected Populations, Range Restrictions, and Statistical Power

    ERIC Educational Resources Information Center

    Miciak, Jeremy; Taylor, W. Pat; Stuebing, Karla K.; Fletcher, Jack M.; Vaughn, Sharon

    2016-01-01

    An appropriate estimate of statistical power is critical for the design of intervention studies. Although the inclusion of a pretest covariate in the test of the primary outcome can increase statistical power, samples selected on the basis of pretest performance may demonstrate range restriction on the selection measure and other correlated…

  5. Aeronautics Study Takes Off! Glider Design for Beginners

    ERIC Educational Resources Information Center

    Lazaros, Edward J.; Carlson, Katie

    2008-01-01

    Study of aeronautics is an interesting and motivating subject for students and educators alike. The activity described in this article--appropriate for upper elementary or middle school students--provides an excellent introduction to airplane design and the science of aerodynamics. It also gives students good experience applying knowledge from a…

  6. PROSPECTIVE PREGNANCY STUDY DESIGNS FOR ASSESSING REPRODUCTIVE AND DEVELOPMENTAL TOXICANTS

    EPA Science Inventory

    Prospective Pregnancy Study Designs for Assessing Reproductive and Developmental Toxicants
    Germaine M. Buck,1 Courtney D. Johnson,1 Joseph Stanford,2 Anne Sweeney,3 Laura Schieve,4 John Rockett,5 Sherry G. Selevan,6 Steve Schrader 7

    Abstract
    The origin of successfu...

  7. Usability Studies and User-Centered Design in Digital Libraries

    ERIC Educational Resources Information Center

    Comeaux, David J.

    2008-01-01

    Digital libraries continue to flourish. At the same time, the principles of user-centered design and the practice of usability testing have been growing in popularity, spreading their influence into the library sphere. This article explores the confluence of these two trends by surveying the current literature on usability studies of digital…

  8. Conflicts Management Model in School: A Mixed Design Study

    ERIC Educational Resources Information Center

    Dogan, Soner

    2016-01-01

    The object of this study is to evaluate the reasons for conflicts occurring in school according to perceptions and views of teachers and resolution strategies used for conflicts and to build a model based on the results obtained. In the research, explanatory design including quantitative and qualitative methods has been used. The quantitative part…

  9. MRFM System Design for the Study of Organic Materials

    NASA Astrophysics Data System (ADS)

    Smith, Doran; Kim, David

    2007-03-01

    We will present an overview of our program to develop an MRFM system specialized for the study of organic materials at 4 K. The system uses the SPAM geometry and the CERMIT protocol and is predicted to be capable of imaging organic materials in 3D. The MRFM probe head design will be overviewed and progress toward system completion will be discussed.

  10. The design and methodology of premature ejaculation interventional studies.

    PubMed

    McMahon, Chris G

    2016-08-01

    Large well-designed clinical efficacy and safety randomized clinical trials (RCTs) are required to achieve regulatory approval of new drug treatments. The objective of this article is to make recommendations for the criteria for defining and selecting the clinical trial study population, design and efficacy outcomes measures which comprise ideal premature ejaculation (PE) interventional trial methodology. Data on clinical trial design, epidemiology, definitions, dimensions and psychological impact of PE was reviewed, critiqued and incorporated into a series of recommendations for standardisation of PE clinical trial design, outcome measures and reporting using the principles of evidence based medicine. Data from PE interventional studies are only reliable, interpretable and capable of being generalised to patients with PE, when study populations are defined by the International Society for Sexual Medicine (ISSM) multivariate definition of PE. PE intervention trials should employ a double-blind RCT methodology and include placebo control, active standard drug control, and/or dose comparison trials. Ejaculatory latency time (ELT) and subject/partner outcome measures of control, personal/partner/relationship distress and other study-specific outcome measures should be used as outcome measures. There is currently no published literature which identifies a clinically significant threshold response to intervention. The ISSM definition of PE reflects the contemporary understanding of PE and represents the state-of-the-art multi-dimensional definition of PE and is recommended as the basis of diagnosis of PE for all PE clinical trials.

  11. Factorial study of rain garden design for nitrogen removal

    EPA Science Inventory

    Abstract Nitrate (〖NO〗_3^--N ) removal studies in bioretention systems showed great variability in removal rates and in some cases 〖NO〗_3^--N was exported. A 3-way factorial design (2 x 2 x 4) was devised for eight outdoor un-vegetated rain gardens to evaluate the effects of ...

  12. Building Futures: The Head Start Impact Study. Research Design Plan.

    ERIC Educational Resources Information Center

    Puma, Michael; Bell, Stephen; Shapiro, Gary; Broene, Pam; Cook, Ronna; Friedman, Janet; Heid, Camilla

    Along with the rapid expansion over the past decade of Head Start, a program providing comprehensive early childhood development services to low-income children, their families, and their communities, has come the demand for rigorous research to demonstrate program effectiveness. This report describes the proposed design of a national study of the…

  13. Aragon workers' health study - design and cohort description

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spain, a Mediterranean country with relatively low rates of coronary heart disease, has a high prevalence of traditional cardiovascular risk factors and is experiencing a severe epidemic of overweight/obesity. We designed the Aragon Workers' Health Study (AWHS) to characterize the factors associated...

  14. Engineering study for the functional design of a multiprocessor system

    NASA Technical Reports Server (NTRS)

    Miller, J. S.; Vandever, W. H.; Stanten, S. F.; Avakian, A. E.; Kosmala, A. L.

    1972-01-01

    The results are presented of a study to generate a functional system design of a multiprocessing computer system capable of satisfying the computational requirements of a space station. These data management system requirements were specified to include: (1) real time control, (2) data processing and storage, (3) data retrieval, and (4) remote terminal servicing.

  15. Space transportation booster engine configuration study. Addendum: Design definition document

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Gas generator engine characteristics and results of engine configuration refinements are discussed. Updated component mechanical design, performance, and manufacturing information is provided. The results are also provided of ocean recovery studies and various engine integration tasks. The details are provided of the maintenance plan for the Space Transportation Booster Engine.

  16. Study Abroad Program Design, Personal Development and Intercultural Effectiveness

    ERIC Educational Resources Information Center

    Wiedenhoeft, Margaret Davis

    2011-01-01

    Research on study abroad focuses on the development of learning outcomes and assessment (Bolen, 2007) or program design, such as level of integration with local student population, housing situation, and level of interaction with host culture (Brecht & Robinson, 1993; Engle & Engle, 2004; Georgetown Consortium Research Project, n.d.;…

  17. Integrated source and channel encoded digital communication system design study

    NASA Technical Reports Server (NTRS)

    Huth, G. K.; Trumpis, B. D.; Udalov, S.

    1975-01-01

    Various aspects of space shuttle communication systems were studied. The following major areas were investigated: burst error correction for shuttle command channels; performance optimization and design considerations for Costas receivers with and without bandpass limiting; experimental techniques for measuring low level spectral components of microwave signals; and potential modulation and coding techniques for the Ku-band return link. Results are presented.

  18. The design and methodology of premature ejaculation interventional studies

    PubMed Central

    2016-01-01

    Large well-designed clinical efficacy and safety randomized clinical trials (RCTs) are required to achieve regulatory approval of new drug treatments. The objective of this article is to make recommendations for the criteria for defining and selecting the clinical trial study population, design and efficacy outcomes measures which comprise ideal premature ejaculation (PE) interventional trial methodology. Data on clinical trial design, epidemiology, definitions, dimensions and psychological impact of PE was reviewed, critiqued and incorporated into a series of recommendations for standardisation of PE clinical trial design, outcome measures and reporting using the principles of evidence based medicine. Data from PE interventional studies are only reliable, interpretable and capable of being generalised to patients with PE, when study populations are defined by the International Society for Sexual Medicine (ISSM) multivariate definition of PE. PE intervention trials should employ a double-blind RCT methodology and include placebo control, active standard drug control, and/or dose comparison trials. Ejaculatory latency time (ELT) and subject/partner outcome measures of control, personal/partner/relationship distress and other study-specific outcome measures should be used as outcome measures. There is currently no published literature which identifies a clinically significant threshold response to intervention. The ISSM definition of PE reflects the contemporary understanding of PE and represents the state-of-the-art multi-dimensional definition of PE and is recommended as the basis of diagnosis of PE for all PE clinical trials. PMID:27652224

  19. Service-Learning and Interior Design: A Case Study

    ERIC Educational Resources Information Center

    Sterling, Mary

    2007-01-01

    The case study approach was used to analyze experiential learning through its three components: knowledge, action, and reflection. Two interior design courses were integrated through a university service-learning project. The restoration/adaptive reuse of a 95-year-old library building was to serve as a prototype for future off-campus…

  20. Designing occupancy studies when false-positive detections occur

    USGS Publications Warehouse

    Clement, Matthew

    2016-01-01

    1.Recently, estimators have been developed to estimate occupancy probabilities when false-positive detections occur during presence-absence surveys. Some of these estimators combine different types of survey data to improve estimates of occupancy. With these estimators, there is a tradeoff between the number of sample units surveyed, and the number and type of surveys at each sample unit. Guidance on efficient design of studies when false positives occur is unavailable. 2.For a range of scenarios, I identified survey designs that minimized the mean square error of the estimate of occupancy. I considered an approach that uses one survey method and two observation states and an approach that uses two survey methods. For each approach, I used numerical methods to identify optimal survey designs when model assumptions were met and parameter values were correctly anticipated, when parameter values were not correctly anticipated, and when the assumption of no unmodelled detection heterogeneity was violated. 3.Under the approach with two observation states, false positive detections increased the number of recommended surveys, relative to standard occupancy models. If parameter values could not be anticipated, pessimism about detection probabilities avoided poor designs. Detection heterogeneity could require more or fewer repeat surveys, depending on parameter values. If model assumptions were met, the approach with two survey methods was inefficient. However, with poor anticipation of parameter values, with detection heterogeneity, or with removal sampling schemes, combining two survey methods could improve estimates of occupancy. 4.Ignoring false positives can yield biased parameter estimates, yet false positives greatly complicate the design of occupancy studies. Specific guidance for major types of false-positive occupancy models, and for two assumption violations common in field data, can conserve survey resources. This guidance can be used to design efficient

  1. Status of the VOTech Design Study about User Tools

    NASA Astrophysics Data System (ADS)

    Dolensky, M.; Pierfederici, F.; Allen, M.; Boch, T.; Bonnarel, F.; Derrière, S.; Fernique, P.; Noddle, K.; Smareglia, R.

    2006-07-01

    The VOTech design study on future tools started in spring 2005. This project, co-funded by the EC, produces design documents and software prototypes for new VO-compliant end-user tools. It is based on the experience and feedback of precursor projects and on input from the scientific user community. This status report details a number of early deliverables available from the project pages wiki.eurovotech.org, section DS4. This includes a summary of existing tools, desired future tools as derived from the AVO SRM, requirements for a cross matcher, a simple method for transferring instrumental footprints, use cases for simulations and the evaluation of various technologies.

  2. Shuttle/tethered satellite system conceptual design study

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A closed-loop control system was added to the tether reel which improves control over the tethered satellite. In addition to increasing the stability of the tethered satellite along local vertical, this control system is used for deployment and retrieval of tethered satellites. This conceptual design study describes a tether system for suspending a science payload at an altitude of 120 km from space shuttle orbiter flying at an altitude of 200 km. In addition to the hardware conceptual designs, various aspects concerning Orbiter accommodations are discussed.

  3. A Taguchi study of the aeroelastic tailoring design process

    NASA Technical Reports Server (NTRS)

    Bohlmann, Jonathan D.; Scott, Robert C.

    1991-01-01

    A Taguchi study was performed to determine the important players in the aeroelastic tailoring design process and to find the best composition of the optimization's objective function. The Wing Aeroelastic Synthesis Procedure (TSO) was used to ascertain the effects that factors such as composite laminate constraints, roll effectiveness constraints, and built-in wing twist and camber have on the optimum, aeroelastically tailored wing skin design. The results show the Taguchi method to be a viable engineering tool for computational inquiries, and provide some valuable lessons about the practice of aeroelastic tailoring.

  4. Advanced study techniques: tools for HVDC systems design

    SciTech Connect

    Degeneff, R.C.

    1984-01-01

    High voltage direct current (HVDC) transmission systems, which offer functional as well as environmental and economic advantages, could see a 15% growth rate over the next decade. Design studies of HVDC system components are complicated by the need to cover 11 major elements: power system, insulation coordination, filter design, subsynchronous torsional interaction, circuit breaker requirements, power line carrier and radio interference, electric fields and audible noise, protective relaying, availability and reliability, efficiency, equipment specification, and HVDC simulator and Transient Network Analyzers. The author summarizes and illustrates each element. 6 figures, 1 table.

  5. Kids in the city study: research design and methodology

    PubMed Central

    2011-01-01

    Background Physical activity is essential for optimal physical and psychological health but substantial declines in children's activity levels have occurred in New Zealand and internationally. Children's independent mobility (i.e., outdoor play and traveling to destinations unsupervised), an integral component of physical activity in childhood, has also declined radically in recent decades. Safety-conscious parenting practices, car reliance and auto-centric urban design have converged to produce children living increasingly sedentary lives. This research investigates how urban neighborhood environments can support or enable or restrict children's independent mobility, thereby influencing physical activity accumulation and participation in daily life. Methods/Design The study is located in six Auckland, New Zealand neighborhoods, diverse in terms of urban design attributes, particularly residential density. Participants comprise 160 children aged 9-11 years and their parents/caregivers. Objective measures (global positioning systems, accelerometers, geographical information systems, observational audits) assessed children's independent mobility and physical activity, neighborhood infrastructure, and streetscape attributes. Parent and child neighborhood perceptions and experiences were assessed using qualitative research methods. Discussion This study is one of the first internationally to examine the association of specific urban design attributes with child independent mobility. Using robust, appropriate, and best practice objective measures, this study provides robust epidemiological information regarding the relationships between the built environment and health outcomes for this population. PMID:21781341

  6. Design and experimental study of a novel giant magnetostrictive actuator

    NASA Astrophysics Data System (ADS)

    Xue, Guangming; Zhang, Peilin; He, Zhongbo; Li, Dongwei; Huang, Yingjie; Xie, Wenqiang

    2016-12-01

    Giant magnetostrictive actuator has been widely used in precise driving occasions for its excellent performance. However, in driving a switching valve, especially the ball-valve in an electronic controlled injector, the actuator can't exhibit its good performance for limits in output displacement and responding speed. A novel giant magnetostrictive actuator, which can reach its maximum displacement for being exerted with no bias magnetic field, is designed in this paper. Simultaneously, elongating of the giant magetostrictive material is converted to shortening of the actuator's axial dimension with the help of an output rod in "T" type. Furthermore, to save responding time, the driving voltage with high opening voltage while low holding voltage is designed. Responding time and output displacement are studied experimentally with the help of a measuring system. From measured results, designed driving voltage can improve the responding speed of actuator displacement quite effectively. And, giant magnetostrictive actuator can output various steady-state displacements to reach more driving effects.

  7. Study of optical design of three-dimensional digital ophthalmoscopes.

    PubMed

    Fang, Yi-Chin; Yen, Chih-Ta; Chu, Chin-Hsien

    2015-10-01

    This study primarily involves using optical zoom structures to design a three-dimensional (3D) human-eye optical sensory system with infrared and visible light. According to experimental data on two-dimensional (2D) and 3D images, human-eye recognition of 3D images is substantially higher (approximately 13.182%) than that of 2D images. Thus, 3D images are more effective than 2D images when they are used at work or in high-recognition devices. In the optical system design, infrared and visible light wavebands were incorporated as light sources to perform simulations. The results can be used to facilitate the design of optical systems suitable for 3D digital ophthalmoscopes.

  8. Design Feasibility Study of a Space Station Freedom Truss

    NASA Technical Reports Server (NTRS)

    Armand, Sasan C.; Dohogne, Caroline A.

    1992-01-01

    Here, the focus is on the design and configuration feasibility of the short spacer for the Space Station Program in its launch configuration. The product of this study is being used by Rockwell International (Rocketdyne Division) as they continue their design concept of the current short spacer configuration. It is anticipated that the launch loads will dominate the on-orbit loads and dictate the design configuration of the short spacer. At the present time, the on-orbit loads have not been generated. The structural analysis discussed herein is based on the transient events derived from the Space Transportation System (STS) Interface Control Document (ICD). The transient loading events consist of liftoff loads, landing loads, and emergency landing loads. The quasi-static loading events have been neglected, since the magnitude of the acceleration factors are lower than the transient acceleration factors. The normal mode analyses presented herein are based on the most feasible configurations with acceptable stress ranges.

  9. Space tug point design study. Volume 1: Summary

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The design and characteristics of a space tug are discussed. The primary objective of the study is to verify the performance capability of a baseline design to deliver and retrieve payloads between 100 nautical miles, 28.5 degrees inclination, and geosynchronous. The space tug is ground based, reusable for 20 mission cycles, and is shuttled to and from low earth orbit by an earth orbital shuttle (EOS) with a 65,000 pound payload capability. It is shown that the baseline concept can meet the target performance goals. The design analysis encompassed: (1) definition of the vehicle primary structure, (2) thermal control, (3) meteoroid protection, (4) propulsion and mechanical subsystems, and (5) avionics including power generation and distribution.

  10. Design feasibility study of a Space Station Freedom truss

    NASA Astrophysics Data System (ADS)

    Armand, Sasan C.; Dohogne, Caroline A.

    1992-04-01

    Here, the focus is on the design and configuration feasibility of the short spacer for the Space Station Program in its launch configuration. The product of this study is being used by Rockwell International (Rocketdyne Division) as they continue their design concept of the current short spacer configuration. It is anticipated that the launch loads will dominate the on-orbit loads and dictate the design configuration of the short spacer. At the present time, the on-orbit loads have not been generated. The structural analysis discussed herein is based on the transient events derived from the Space Transportation System (STS) Interface Control Document (ICD). The transient loading events consist of liftoff loads, landing loads, and emergency landing loads. The quasi-static loading events have been neglected, since the magnitude of the acceleration factors are lower than the transient acceleration factors. The normal mode analyses presented herein are based on the most feasible configurations with acceptable stress ranges.

  11. Advanced Technology Spark-Ignition Aircraft Piston Engine Design Study

    NASA Technical Reports Server (NTRS)

    Stuckas, K. J.

    1980-01-01

    The advanced technology, spark ignition, aircraft piston engine design study was conducted to determine the improvements that could be made by taking advantage of technology that could reasonably be expected to be made available for an engine intended for production by January 1, 1990. Two engines were proposed to account for levels of technology considered to be moderate risk and high risk. The moderate risk technology engine is a homogeneous charge engine operating on avgas and offers a 40% improvement in transportation efficiency over present designs. The high risk technology engine, with a stratified charge combustion system using kerosene-based jet fuel, projects a 65% improvement in transportation efficiency. Technology enablement program plans are proposed herein to set a timetable for the successful integration of each item of required advanced technology into the engine design.

  12. Design studies of continuously variable transmissions for electric vehicles

    NASA Technical Reports Server (NTRS)

    Parker, R. J.; Loewenthal, S. H.; Fischer, G. K.

    1981-01-01

    Preliminary design studies were performed on four continuously variable transmission (CVT) concepts for use with a flywheel equipped electric vehicle of 1700 kg gross weight. Requirements of the CVT's were a maximum torque of 450 N-m (330 lb-ft), a maximum output power of 75 kW (100 hp), and a flywheel speed range of 28,000 to 14,000 rpm. Efficiency, size, weight, cost, reliability, maintainability, and controls were evaluated for each of the four concepts which included a steel V-belt type, a flat rubber belt type, a toroidal traction type, and a cone roller traction type. All CVT's exhibited relatively high calculated efficiencies (68 percent to 97 percent) over a broad range of vehicle operating conditions. Estimated weight and size of these transmissions were comparable to or less than equivalent automatic transmission. The design of each concept was carried through the design layout stage.

  13. Laser fusion driven breeder design study. Final report

    SciTech Connect

    Berwald, D.H.; Massey, J.V.

    1980-12-01

    The results of the Laser Fusion Breeder Design Study are given. This information primarily relates to the conceptual design of an inertial confinement fusion (ICF) breeder reactor (or fusion-fission hybrid) based upon the HYLIFE liquid metal wall protection concept developed at Lawrence Livermore National Laboratory. The blanket design for this breeder is optimized to both reduce fissions and maximize the production of fissile fuel for subsequent use in conventional light water reactors (LWRs). When the suppressed fission blanket is compared with its fast fission counterparts, a minimal fission rate in the blanket results in a unique reactor safety advantage for this concept with respect to reduced radioactive inventory and reduced fission product decay afterheat in the event of a loss-of-coolant-accident.

  14. LUTE primary mirror materials and design study report

    NASA Technical Reports Server (NTRS)

    Ruthven, Greg

    1993-01-01

    The major objective of the Lunar Ultraviolet Telescope Experiment (LUTE) Primary Mirror Materials and Design Study is to investigate the feasibility of the LUTE telescope primary mirror. A systematic approach to accomplish this key goal was taken by first understanding the optical, thermal, and structural requirements and then deriving the critical primary mirror-level requirements for ground testing, launch, and lunar operations. After summarizing the results in those requirements which drove the selection of material and the design for the primary mirror are discussed. Most important of these are the optical design which was assumed to be the MSFC baseline (i.e. 3 mirror optical system), telescope wavefront error (WFE) allocations, the telescope weight budget, and the LUTE operational temperature ranges. Mechanical load levels, reflectance and microroughness issues, and options for the LUTE metering structure were discussed and an outline for the LUTE telescope sub-system design specification was initiated. The primary mirror analysis and results are presented. The six material substrate candidates are discussed and four distinct mirror geometries which are considered are shown. With these materials and configurations together with varying the location of the mirror support points, a total of 42 possible primary mirror designs resulted. The polishability of each substrate candidate was investigated and a usage history of 0.5 meter and larger precision cryogenic mirrors (the operational low end LUTE temperature of 60 K is the reason we feel a survey of cryogenic mirrors is appropriate) that were flown or tested are presented.

  15. Mixed methods research design for pragmatic psychoanalytic studies.

    PubMed

    Tillman, Jane G; Clemence, A Jill; Stevens, Jennifer L

    2011-10-01

    Calls for more rigorous psychoanalytic studies have increased over the past decade. The field has been divided by those who assert that psychoanalysis is properly a hermeneutic endeavor and those who see it as a science. A comparable debate is found in research methodology, where qualitative and quantitative methods have often been seen as occupying orthogonal positions. Recently, Mixed Methods Research (MMR) has emerged as a viable "third community" of research, pursuing a pragmatic approach to research endeavors through integrating qualitative and quantitative procedures in a single study design. Mixed Methods Research designs and the terminology associated with this emerging approach are explained, after which the methodology is explored as a potential integrative approach to a psychoanalytic human science. Both qualitative and quantitative research methods are reviewed, as well as how they may be used in Mixed Methods Research to study complex human phenomena.

  16. Statistical Design Features of the Healthy Communities Study.

    PubMed

    Strauss, Warren J; Sroka, Christopher J; Frongillo, Edward A; Arteaga, S Sonia; Loria, Catherine M; Leifer, Eric S; Wu, Colin O; Patrick, Heather; Fishbein, Howard A; John, Lisa V

    2015-10-01

    The Healthy Communities Study is designed to assess relationships between characteristics of community programs and policies targeting childhood obesity and children's BMI, diet, and physical activity. The study involved a complex data collection protocol implemented over a 2-year period (2013-2015) across a diverse sample of 130 communities, defined as public high school catchment areas. The protocol involved baseline assessment within each community that included in-person or telephone interviews regarding community programs and policies and in-home collection of BMI, nutritional, and physical activity outcomes from a sample of up to 81 children enrolled in kindergarten through eighth grade in public schools. The protocol also involved medical record reviews to establish a longitudinal trajectory of BMI for an estimated 70% of participating children. Staged sampling was used to collect less detailed measures of physical activity and nutrition across the entire sample of children, with a subset assessed using more costly, burdensome, and detailed measures. Data from the Healthy Community Study will be analyzed using both cross-sectional and longitudinal models that account for the complex design and correct for measurement error and bias using a likelihood-based Markov-chain Monte Carlo methodology. This methods paper provides insights into the complex design features of the Healthy Communities Study and may serve as an example for future large-scale studies that assess the relationship between community-based programs and policies and health outcomes of community residents.

  17. Statistical Design Features of the Healthy Communities Study

    PubMed Central

    Strauss, Warren J.; Sroka, Christopher J.; Frongillo, Edward A.; Arteaga, S. Sonia; Loria, Catherine M.; Leifer, Eric S.; Wu, Colin O.; Patrick, Heather; Fishbein, Howard A.; John, Lisa V.

    2015-01-01

    The Healthy Communities Study is designed to assess relationships between characteristics of community programs and policies targeting childhood obesity and children’s BMI, diet, and physical activity. The study involved a complex data collection protocol implemented over a 2-year period (2013–2015) across a diverse sample of up to 125 communities, defined as public high school catchment areas. The protocol involved baseline assessment within each community that included in-person or telephone interviews regarding community programs and policies and in-home collection of BMI, nutritional, and physical activity outcomes from a sample of up to 81 children enrolled in kindergarten through eighth grade in public schools. The protocol also involved medical record reviews to establish a longitudinal trajectory of BMI for an estimated 70% of participating children. Staged sampling was used to collect less detailed measures of physical activity and nutrition across the entire sample of children, with a subset assessed using more costly, burdensome, and detailed measures. Data from the Healthy Community Study will be analyzed using both cross-sectional and longitudinal models that account for the complex design and correct for measurement error and bias using a likelihood-based Markov chain Monte Carlo methodology. This methods paper provides insights into the complex design features of the Healthy Communities Study and may serve as an example for future large-scale studies that assess the relationship between community-based programs and policies and health outcomes of community residents. PMID:26384932

  18. Methodological considerations for designing a community water fluoridation cessation study.

    PubMed

    Singhal, Sonica; Farmer, Julie; McLaren, Lindsay

    2017-02-22

    High-quality, up-to-date research on community water fluoridation (CWF), and especially on the implications of CWF cessation for dental health, is limited. Although CWF cessation studies have been conducted, they are few in number; one of the major reasons is the methodological complexity of conducting such a study. This article draws on a systematic review of existing cessation studies (n=15) to explore methodological considerations of conducting CWF cessation studies in future. We review nine important methodological aspects (study design, comparison community, target population, time frame, sampling strategy, clinical indicators, assessment criteria, covariates and biomarkers) and provide recommendations for planning future CWF cessation studies that examine effects on dental caries. There is no one ideal study design to answer a research question. However, recommendations proposed regarding methodological aspects to conduct an epidemiological study to observe the effects of CWF cessation on dental caries, coupled with our identification of important methodological gaps, will be useful for researchers who are looking to optimize resources to conduct such a study with standards of rigour.

  19. Energy efficient engine preliminary design and integration study

    NASA Technical Reports Server (NTRS)

    Gray, D. E.

    1978-01-01

    The technology and configurational requirements of an all new 1990's energy efficient turbofan engine having a twin spool arrangement with a directly coupled fan and low-pressure turbine, a mixed exhaust nacelle, and a high 38.6:1 overall pressure ratio were studied. Major advanced technology design features required to provide the overall benefits were a high pressure ratio compression system, a thermally actuated advanced clearance control system, lightweight shroudless fan blades, a low maintenance cost one-stage high pressure turbine, a short efficient mixer and structurally integrated engine and nacelle. A conceptual design analysis was followed by integration and performance analyses of geared and direct-drive fan engines with separate or mixed exhaust nacelles to refine previously designed engine cycles. Preliminary design and more detailed engine-aircraft integration analysis were then conducted on the more promising configurations. Engine and aircraft sizing, fuel burned, and airframe noise studies on projected 1990's domestic and international aircraft produced sufficient definition of configurational and advanced technology requirements to allow immediate initiation of component technology development.

  20. Controlled Ecological Life Support Systems (CELSS) conceptual design option study

    NASA Technical Reports Server (NTRS)

    Oleson, Melvin; Olson, Richard L.

    1986-01-01

    Results are given of a study to explore options for the development of a Controlled Ecological Life Support System (CELSS) for a future Space Station. In addition, study results will benefit the design of other facilities such as the Life Sciences Research Facility, a ground-based CELSS demonstrator, and will be useful in planning longer range missions such as a lunar base or manned Mars mission. The objectives were to develop weight and cost estimates for one CELSS module selected from a set of preliminary plant growth unit (PGU) design options. Eleven Space Station CELSS module conceptual PGU designs were reviewed, components and subsystems identified and a sensitivity analysis performed. Areas where insufficient data is available were identified and divided into the categories of biological research, engineering research, and technology development. Topics which receive significant attention are lighting systems for the PGU, the use of automation within the CELSS system, and electric power requirements. Other areas examined include plant harvesting and processing, crop mix analysis, air circulation and atmosphere contaminant flow subsystems, thermal control considerations, utility routing including accessibility and maintenance, and nutrient subsystem design.

  1. Design study of flat belt CVT for electric vehicles

    NASA Technical Reports Server (NTRS)

    Kumm, E. L.

    1980-01-01

    A continuously variable transmission (CVT) was studied, using a novel flat belt pulley arrangement which couples the high speed output shaft of an energy storage flywheel to the drive train of an electric vehicle. A specific CVT arrangement was recommended and its components were selected and sized, based on the design requirements of a 1700 KG vehicle. A design layout was prepared and engineering calculations made of component efficiencies and operating life. The transmission efficiency was calculated to be significantly over 90% with the expected vehicle operation. A design consistent with automotive practice for low future production costs was considered, together with maintainability. The technology advancements required to develop the flat belt CVT were identified and an estimate was made of how the size of the flat belt CVT scales to larger and smaller design output torques. The suitability of the flat belt CVT for alternate application to an electric vehicle powered by an electric motor without flywheel and to a hybrid electric vehicle powered by an electric motor with an internal combustion engine was studied.

  2. New design studies for TRIUMF's ARIEL High Resolution Separator

    NASA Astrophysics Data System (ADS)

    Maloney, J. A.; Baartman, R.; Marchetto, M.

    2016-06-01

    As part of its new Advanced Rare IsotopE Laboratory (ARIEL), TRIUMF is designing a novel High Resolution Separator (HRS) (Maloney et al., 2015) to separate rare isotopes. The HRS has a 180° bend, separated into two 90° magnetic dipoles, bend radius 1.2 m, with an electrostatic multipole corrector between them. Second order correction comes mainly from the dipole edge curvatures, but is intended to be fine-tuned with a sextupole component and a small octupole component in the multipole. This combination is designed to achieve 1:20,000 resolution for a 3 μm (horizontal) and 6 μm (vertical) emittance. A design for the HRS dipole magnets achieves both radial and integral flatness goals of <10-5. A review of the optical design for the HRS is presented, including the study of limiting factors affecting separation, matching and aberration correction. Field simulations from the OPERA-3D (OPERA) [2] models of the dipole magnets are used in COSY Infinity (COSY) (Berz and Makino, 2005) [3] to find and optimize the transfer maps to 3rd order and study residual nonlinearities to 8th order.

  3. METIS opto-mechanical design and packaging study

    NASA Astrophysics Data System (ADS)

    Kroes, Gabby; ter Horst, Rik; Kragt, Jan; Roelfsema, Ronald; Navarro, Ramón; Venema, Lars; Lenzen, Rainer; Rohloff, Ralf R.; Durand, Gilles; Pantin, Eric; Ronayette, Samuel; Todd, Stephen; Bennett, Richard; Glasse, Alistair; Blommaert, Joris; Brandl, Bernhard; Teuwen, Maurice; Janssen, Huub; Huisman, Robert

    2010-07-01

    METIS: "Mid-infrared ELT Imager and Spectrograph" is the mid-infrared (3 - 14 microns) instrument for imaging and spectroscopy for the European Extremely Large Telescope (E-ELT). To ensure high detection sensitivity the internal radiation of the instrument needs to be eliminated (sufficiently reduced) and thus needs to be operated at cryogenic temperatures. The instrument is divided in a cold and warm system. The cold system, the actual heart of the system, is subdivided into five main opto-mechanical modules located within a common cryostat (part of the warm system). The warm system provides the crucial environment for the cold system, including the instrument control and maintenance equipment. The end 2009 finished Phase-A study carried out within the framework of the ESO sponsored E-ELT instrumentation studies has been performed by an international consortium with institutes from Netherlands (PI: Bernhard Brandl - NOVA), Germany, France, United Kingdom and Belgium. During this conference various aspects of the METIS instrument (design) are presented in several papers, including the instrument concept and science case, and the system engineering and optical design. This paper describes the design constraints and key issues regarding the packaging of this complex cryogenic instrument. The design solutions to create a light, small and fully accessible instrument are discussed together with the specific subdivision of the cold and warm system to ensure concurrent development at various different institutes around Europe. In addition the paper addresses the design and development studies for the special, challenging units such as the large optical image de-rotator, the (2D) chopper mechanism and the special cryogenic drives.

  4. Searching for missing heritability: Designing rare variant association studies

    PubMed Central

    Zuk, Or; Schaffner, Stephen F.; Samocha, Kaitlin; Do, Ron; Hechter, Eliana; Kathiresan, Sekar; Daly, Mark J.; Neale, Benjamin M.; Sunyaev, Shamil R.; Lander, Eric S.

    2014-01-01

    Genetic studies have revealed thousands of loci predisposing to hundreds of human diseases and traits, revealing important biological pathways and defining novel therapeutic hypotheses. However, the genes discovered to date typically explain less than half of the apparent heritability. Because efforts have largely focused on common genetic variants, one hypothesis is that much of the missing heritability is due to rare genetic variants. Studies of common variants are typically referred to as genomewide association studies, whereas studies of rare variants are often simply called sequencing studies. Because they are actually closely related, we use the terms common variant association study (CVAS) and rare variant association study (RVAS). In this paper, we outline the similarities and differences between RVAS and CVAS and describe a conceptual framework for the design of RVAS. We apply the framework to address key questions about the sample sizes needed to detect association, the relative merits of testing disruptive alleles vs. missense alleles, frequency thresholds for filtering alleles, the value of predictors of the functional impact of missense alleles, the potential utility of isolated populations, the value of gene-set analysis, and the utility of de novo mutations. The optimal design depends critically on the selection coefficient against deleterious alleles and thus varies across genes. The analysis shows that common variant and rare variant studies require similarly large sample collections. In particular, a well-powered RVAS should involve discovery sets with at least 25,000 cases, together with a substantial replication set. PMID:24443550

  5. Bridging Translation by Improving Preclinical Study Design in AKI.

    PubMed

    de Caestecker, Mark; Humphreys, Ben D; Liu, Kathleen D; Fissell, William H; Cerda, Jorge; Nolin, Thomas D; Askenazi, David; Mour, Girish; Harrell, Frank E; Pullen, Nick; Okusa, Mark D; Faubel, Sarah

    2015-12-01

    Despite extensive research, no therapeutic interventions have been shown to prevent AKI, accelerate recovery of AKI, or reduce progression of AKI to CKD in patients. This failure in translation has led investigators to speculate that the animal models being used do not predict therapeutic responses in humans. Although this issue continues to be debated, an important concern that has not been addressed is whether improvements in preclinical study design can be identified that might also increase the likelihood of translating basic AKI research into clinical practice using the current models. In this review, we have taken an evidence-based approach to identify common weaknesses in study design and reporting in preclinical AKI research that may contribute to the poor translatability of the findings. We focused on use of N-acetylcysteine or sodium bicarbonate for the prevention of contrast-induced AKI and use of erythropoietin for the prevention of AKI, two therapeutic approaches that have been extensively studied in clinical trials. On the basis of our findings, we identified five areas for improvement in preclinical study design and reporting. These suggested and preliminary guidelines may help improve the quality of preclinical research for AKI drug development.

  6. Bridging Translation by Improving Preclinical Study Design in AKI

    PubMed Central

    Humphreys, Ben D.; Liu, Kathleen D.; Fissell, William H.; Cerda, Jorge; Nolin, Thomas D.; Askenazi, David; Mour, Girish; Harrell, Frank E.; Pullen, Nick; Okusa, Mark D.

    2015-01-01

    Despite extensive research, no therapeutic interventions have been shown to prevent AKI, accelerate recovery of AKI, or reduce progression of AKI to CKD in patients. This failure in translation has led investigators to speculate that the animal models being used do not predict therapeutic responses in humans. Although this issue continues to be debated, an important concern that has not been addressed is whether improvements in preclinical study design can be identified that might also increase the likelihood of translating basic AKI research into clinical practice using the current models. In this review, we have taken an evidence-based approach to identify common weaknesses in study design and reporting in preclinical AKI research that may contribute to the poor translatability of the findings. We focused on use of N-acetylcysteine or sodium bicarbonate for the prevention of contrast-induced AKI and use of erythropoietin for the prevention of AKI, two therapeutic approaches that have been extensively studied in clinical trials. On the basis of our findings, we identified five areas for improvement in preclinical study design and reporting. These suggested and preliminary guidelines may help improve the quality of preclinical research for AKI drug development. PMID:26538634

  7. Designing alternative splicing RNA-seq studies. Beyond generic guidelines

    PubMed Central

    Stephan-Otto Attolini, Camille; Peña, Victor; Rossell, David

    2015-01-01

    Motivation: Designing an RNA-seq study depends critically on its specific goals, technology and underlying biology, which renders general guidelines inadequate. We propose a Bayesian framework to customize experiments so that goals can be attained and resources are not wasted, with a focus on alternative splicing. Results: We studied how read length, sequencing depth, library preparation and the number of replicates affects cost-effectiveness of single-sample and group comparison studies. Optimal settings varied strongly according to the target organism or tissue (potential 50–500% cost cuts) and, interestingly, short reads outperformed long reads for standard analyses. Our framework learns key characteristics for study design from the data, and predicts if and how to continue experimentation. These predictions matched several follow-up experimental datasets that were used for validation. We provide default pipelines, but the framework can be combined with other data analysis methods and can help assess their relative merits. Availability and implementation: casper package at www.bioconductor.org/packages/release/bioc/html/casper.html, Supplementary Manual by typing casperDesign() at the R prompt. Contact: rosselldavid@gmail.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26220961

  8. Summary of the Preliminary Optical ICHMI Design Study: A Preliminary Engineering Design Study for a Standpipe Viewport

    SciTech Connect

    Anheier, Norman C.; Qiao, Hong; Berglin, Eric J.; Hatchell, Brian K.

    2013-12-26

    This summary report examines an in-vessel optical access concept intended to support standoff optical instrumentation, control and human-machine interface (ICHMI) systems for future advanced small modular reactor (AdvSMR) applications. Optical-based measurement and sensing systems for AdvSMR applications have several key benefits over traditional instrumentation and control systems used to monitor reactor process parameters, such as temperature, flow rate, pressure, and coolant chemistry (Anheier et al. 2013). Direct and continuous visualization of the in-vessel components can be maintained using external cameras. Many optical sensing techniques can be performed remotely using open optical beam path configurations. Not only are in-vessel cables eliminated by these configurations, but also sensitive optical monitoring components (e.g., electronics, lasers, detectors, and cameras) can be placed outside the reactor vessel in the instrument vault, containment building, or other locations where temperatures and radiation levels are much lower. However, the extreme AdvSMR environment present challenges for optical access designs and optical materials. Optical access is not provided in any commercial nuclear power plant or featured in any reactor design, although successful implementation of optical access has been demonstrated in test reactors (Arkani and Gharib 2009). This report outlines the key engineering considerations for an AdvSMR optical access concept. Strict American Society of Mechanical Engineers (ASME) construction codes must be followed for any U.S. nuclear facility component (ASME 2013); however, the scope of this study is to evaluate the preliminary engineering issues for this concept, rather than developing a nuclear-qualified design. In addition, this study does not consider accident design requirements. In-vessel optical access using a standpipe viewport concept serves as a test case to explore the engineering challenges and performance requirements

  9. Study of Turbofan Engines Designed for Low Enery Consumption

    NASA Technical Reports Server (NTRS)

    Neitzel, R. E.; Hirschkron, R.; Johnston, R. P.

    1976-01-01

    Subsonic transport turbofan engine design and technology features which have promise of improving aircraft energy consumption are described. Task I addressed the selection and evaluation of features for the CF6 family of engines in current aircraft, and growth models of these aircraft. Task II involved cycle studies and the evaluation of technology features for advanced technology turbofans, consistent with initial service in 1985. Task III pursued the refined analysis of a specific design of an advanced technology turbofan engine selected as the result of Task II studies. In all of the above, the impact upon aircraft economics, as well as energy consumption, was evaluated. Task IV summarized recommendations for technology developments which would be necessary to achieve the improvements in energy consumption identified.

  10. Optimal design in pediatric pharmacokinetic and pharmacodynamic clinical studies.

    PubMed

    Roberts, Jessica K; Stockmann, Chris; Balch, Alfred; Yu, Tian; Ward, Robert M; Spigarelli, Michael G; Sherwin, Catherine M T

    2015-03-01

    It is not trivial to conduct clinical trials with pediatric participants. Ethical, logistical, and financial considerations add to the complexity of pediatric studies. Optimal design theory allows investigators the opportunity to apply mathematical optimization algorithms to define how to structure their data collection to answer focused research questions. These techniques can be used to determine an optimal sample size, optimal sample times, and the number of samples required for pharmacokinetic and pharmacodynamic studies. The aim of this review is to demonstrate how to determine optimal sample size, optimal sample times, and the number of samples required from each patient by presenting specific examples using optimal design tools. Additionally, this review aims to discuss the relative usefulness of sparse vs rich data. This review is intended to educate the clinician, as well as the basic research scientist, whom plan on conducting a pharmacokinetic/pharmacodynamic clinical trial in pediatric patients.

  11. Advanced stratified charge rotary aircraft engine design study

    NASA Technical Reports Server (NTRS)

    Badgley, P.; Berkowitz, M.; Jones, C.; Myers, D.; Norwood, E.; Pratt, W. B.; Ellis, D. R.; Huggins, G.; Mueller, A.; Hembrey, J. H.

    1982-01-01

    A technology base of new developments which offered potential benefits to a general aviation engine was compiled and ranked. Using design approaches selected from the ranked list, conceptual design studies were performed of an advanced and a highly advanced engine sized to provide 186/250 shaft Kw/HP under cruise conditions at 7620/25,000 m/ft altitude. These are turbocharged, direct-injected stratified charge engines intended for commercial introduction in the early 1990's. The engine descriptive data includes tables, curves, and drawings depicting configuration, performance, weights and sizes, heat rejection, ignition and fuel injection system descriptions, maintenance requirements, and scaling data for varying power. An engine-airframe integration study of the resulting engines in advanced airframes was performed on a comparative basis with current production type engines. The results show airplane performance, costs, noise & installation factors. The rotary-engined airplanes display substantial improvements over the baseline, including 30 to 35% lower fuel usage.

  12. Design study of a medical proton linac for neutron therapy

    SciTech Connect

    Machida, S.; Raparia, D.

    1988-08-26

    This paper describes a design study which establishes the physical parameters of the low energy beam transport, radiofrequency quadrupole, and linac, using computer programs available at Fermilab. Beam dynamics studies verify that the desired beam parameters can be achieved. The machine described here meets the aforementioned requirements and can be built using existing technology. Also discussed are other technically feasible options which could be attractive to clinicians, though they would complicate the design of the machine and increase construction costs. One of these options would allow the machine to deliver 2.3 MeV protons to produce epithermal neutrons for treating brain tumors. A second option would provide 15 MeV protons for isotope production. 21 refs., 33 figs.

  13. Satellite Servicing in Mission Design Studies at the NASA GSFC

    NASA Technical Reports Server (NTRS)

    Leete, Stephen J.

    2003-01-01

    Several NASA missions in various stages of development have undergone one-week studies in the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) Integrated Mission Design Center (IMDC), mostly in preparation for proposals. The possible role of satellite servicing has been investigated for several of these missions, applying the lessons learned from Hubble Space Telescope (HST) servicing, taking into account the current state of the art, projecting into the future, and implementing NASA long-range plans, and is presented here. The general benefits and costs of injecting satellite servicing are detailed, including components such as mission timeline, mass, fuel, spacecraft design, risk abatement, life extension, and improved performance. The approach taken in addressing satellite servicing during IMDC studies is presented.

  14. Thermal-structural combined loads design criteria study

    NASA Technical Reports Server (NTRS)

    Deriugin, V.; Brogren, E. W.; Jaeck, C. L.; Brown, A. L.; Clingan, B. E.

    1972-01-01

    A study was conducted to determine methodology for combining thermal structural loads and assessing the effects of the combined loads on the design of a thermal protection system and a hot structure of a high cross range delta wing space shuttle orbiter vehicle. The study presents guidelines for establishing a basis for predicting thermal and pressure environments and for determining limit and ultimate design loads on the vehicle during reentry. Limit trajectories were determined by using dispersions on a representative nominal mission and system parameters expected during the life of the vehicle. Nine chosen locations on the vehicle surface having TPS or hot structures were examined, and weight sensitivity analyses were performed for each location.

  15. Preliminary space station solar array structural design study

    NASA Technical Reports Server (NTRS)

    Dorsey, J. T.; Bush, H. G.; Mikulas, M. M., Jr.

    1984-01-01

    Structurally efficient ways to support the large solar arrays (3,716 square meters which are currently considered for space station use) are examined. An erectable truss concept is presented for the on orbit construction of winged solar arrays. The means for future growth, maintenance, and repair are integrally designed into this concept. Results from parametric studies, which highlight the physical and structural differences between various configuration options are presented. Consideration is given to both solar blanket and hard panel arrays.

  16. DESIGNING STUDIES AND COLLECTING DATA USEFUL FOR CUMULATIVE RISK ASSESSMENT

    EPA Science Inventory

    DESIGNING STUDIES AND COLLECTING DATA USEFUL FOR CUMULATIVE RISK ASSESSMENT. J E Simmons1, C Gennings2, M Casey2, M J Plewa3, E D Wagner3, W H Carter, Jr.2, A McDonald1,Y M Sey1, L K Teuschler3 1NHEERL, ORD, U.S. EPA, RTP NC, USA; 2VCU, Richmond, VA, USA;3Univ. Illinois, Urba...

  17. Advanced Design Composite Aircraft (ADCA) Study. Volume I

    DTIC Science & Technology

    1976-11-01

    6.2.2 Initial Cost Comparisons 397 6.2.3 Reliability and Maintainability Analysis 402 6.2.4 Updated Vehicle Sizing Studies 403 6.2. 5 Resized...upon the configuration to develop a reliable , achievable, baseline design. In particular, the achievement of excellent supersonic performance...and subsystems arranged for best performance and most reliable operation. The location of avionics, weapons and crew systems in the forward section

  18. Transonic Fan/Compressor Rotor Design Study. Volume 4

    DTIC Science & Technology

    1982-02-01

    amd Identify by block number) Fan Aircraft Engines Compressor Blade Thickness Rotor Camber Distribution Aerodesign Throat Margin Aerodynamics 20...COMPRESSOR ROTOR DESIGN STUDY Volume IV D.E. Parker and M.R. Simonson General Electric Company Aircraft Engine Business Group Advanced Technology...Compressor Research Group Chief, Technology Branch FOR THE COMMANDER H. IVAN BUS Director, Turbine Engine Division If your address has changed, if you

  19. Transonic Fan/Compressor Rotor Design Study. Volume 2

    DTIC Science & Technology

    1982-02-01

    Identity by block number) Fan Aircraft Engines Compressor Blade Thickness Rotor Camber Distribution Aerodesign Throat Margin Aerodynamics 20. 1ABSRACT...COMPRESSOR ROTOR DESIGN STUDY Volume II D.E. Parker and M.R. Simonson General Electric Company / Aircraft Engine Business Group Advanced Technology...Research Group Chief, Technology Branch FOR THE COMMANDER H. IVAN BUSH Director, Turbine Engine Division . If your address has changed, if you wish to be

  20. Transonic Fan/Compressor Rotor Design Study. Volume 3

    DTIC Science & Technology

    1982-02-01

    KEY WORDS (Continue on revere. old. $1 nocoeoary and identify by block nuvb.,) Fan Aircraft Engines Compressor Blade Thickne)s Rotor Camber...COMPRESSOR ’Q ROTOR DESIGN STUDY Volume III D.E. Parker and M.R. Simonson CZ) General Electric Company Aircraft Engine Business Group Advanced...Compressor Research Group Chief, Technology Branch FOR THE COMMANDER H. WAN BI Director, Turbine Engine Division ŕ *If your address has changed, if you wish

  1. Innovative Strategic Aircraft Design Study (ISADS) Phase 1

    DTIC Science & Technology

    1978-06-01

    34uS P ? AS Rockwell International Corp, LADE 63314 . Q302ll Los Angeles International Airport, Los Angeles, CA PE634F j HCONrI110.ING OPFICI NAME AND...I p UNCLASSIFIED Section I ’ INTRODUCTION PROGRAM OVERVIEW (U) The Innovative Strategic Aircraft Design Study (ISADS) was sponsored by the Air Force...Robinson served as program manager, assisted by Daniel P . Raymer, deputy program manager. Individual tasks were directed by project managers from the

  2. Gradient-index ophthalmic lens design and polymer material studies

    NASA Astrophysics Data System (ADS)

    Fischer, David Joel

    Unifocal ophthalmic lenses are conventionally designed using homogeneous glass or plastic materials and aspheric surfaces. The desired power and aberration correction are provided by selection of surface shape and refractive index. This thesis studies the design of ophthalmic lenses utilizing gradient-index (GRIN) materials for both the optical power and aberration control. This is done using geometrical optical theory and ray-tracing simulations. Progressive addition lenses (PALS) are vision correction lenses with a continuous change in power used to treat presbyopia. The power variation is typically located in the lower half of the lens. Progressive addition lenses are currently made with aspheric surfaces to achieve the focal power transition and aberration control. These surfaces have at most, mirror symmetry about the vertical axis. The possible design of progressive addition lenses with GRIN materials has not been well studied. This thesis studies PALS and identifies how gradient-index materials can be used to provide both the power progression and aberration control. The optical theory for rotationally symmetric and asymmetric power additions is given. Analytical and numerical methods for calculating the index profile are used, and the results examined using ray-tracing simulations. The theory developed for ophthalmic lenses is applied to the design of GRIN axicon. This is the first GRIN axicon manufactured, and is fabricated using ion-exchanged GRIN glass. Experimental measurements of its performance are compared and found to match theoretical predictions. This demonstrates the generality of the theory developed: it may be applied to non-visual applications, and even to non-imaging applications. Realistic implementation of GRIN technology to ophthalmic application requires the fabrication of large scale refractive index gradients in polymer material systems. The methyl-methacrylate/styrene copolymer system is studied to develop an empirical model of its

  3. Design Studies of ''Island'' Type MOX Lead Test Assembly

    SciTech Connect

    Pavlovitchev, A.M.

    2000-03-31

    In this document the results of neutronics studies of <> type MOX LTA design are presented. The characteristics both for infinite MOX grids and for VVER-1000 core with 3 MOX LTAs are calculated. the neutronics parameters of MOX fueled core have been performed using the Russian 3D code BIPR-7A and 2D code PERMAK-A with the constants prepared by the cell spectrum code TVS-M.

  4. EDIN design study alternate space shuttle booster replacement concepts. Volume 2: Design simulation results

    NASA Technical Reports Server (NTRS)

    Demakes, P. T.; Hirsch, G. N.; Stewart, W. A.; Glatt, C. R.

    1976-01-01

    Historical weight estimating relationships were developed for the liquid rocket booster (LRB) using Saturn technology, and modified as required to support the EDIN05 study. Mission performance was computed using February 1975 shuttle configuration groundrules to allow reasonable comparison of the existing shuttle with the EDIN05 designs. The launch trajectory was constrained to pass through both the RTLS/AOA and main engine cut-off points. Performance analysis was based on a point design trajectory model which optimized initial tilt rate and exo-atmospheric pitch profile. A gravity turn was employed during the boost phase in place of the shuttle angle-of-attack profile. Engine throttling add/or shutdown was used to constrain dynamic pressure and/or longitudinal acceleration where necessary.

  5. Overcoming ecologic bias using the two-phase study design.

    PubMed

    Wakefield, Jon; Haneuse, Sebastien J-P A

    2008-04-15

    Ecologic (aggregate) data are widely available and widely utilized in epidemiologic studies. However, ecologic bias, which arises because aggregate data cannot characterize within-group variability in exposure and confounder variables, can only be removed by supplementing ecologic data with individual-level data. Here the authors describe the two-phase study design as a framework for achieving this objective. In phase 1, outcomes are stratified by any combination of area, confounders, and error-prone (or discretized) versions of exposures of interest. Phase 2 data, sampled within each phase 1 stratum, provide accurate measures of exposure and possibly of additional confounders. The phase 1 aggregate-level data provide a high level of statistical power and a cross-classification by which individuals may be efficiently sampled in phase 2. The phase 2 individual-level data then provide a control for ecologic bias by characterizing the within-area variability in exposures and confounders. In this paper, the authors illustrate the two-phase study design by estimating the association between infant mortality and birth weight in several regions of North Carolina for 2000-2004, controlling for gender and race. This example shows that the two-phase design removes ecologic bias and produces gains in efficiency over the use of case-control data alone. The authors discuss the advantages and disadvantages of the approach.

  6. [The research protocol II: study designs in clinical research].

    PubMed

    Villasís-Keever, Miguel Ángel; Miranda-Novales, María Guadalupe

    2016-01-01

    In clinical research that takes place in health-care areas, most of the studies are performed with human beings as research subjects. The main objectives of these studies are to know the characteristics of one or more groups, the behavior of human diseases, the etiology or causes of diseases, to identify the best diagnostic tools, or to establish the best treatment for a condition or disease in particular. Additionally, some studies are classified as basic bio-medical research; in these investigations, the subjects of study are laboratory animals, tissues, cells, or molecules. In general terms, the objectives of these studies are to understand the physiology, pathogenesis, or biological mechanisms that could explain functions or alterations in one or more systems or body organs. This article will only address clinical research designs.

  7. SDU 6 MODELING STUDY TO SUPPORT DESIGN DEVELOPMENT

    SciTech Connect

    Smith, F.

    2012-05-02

    In response to Technical Task Request (TTR) HLW-SSF-TTR-2012-0017 (1), SRNL performed modeling studies to evaluate alternative design features for the 32 million gallon Saltstone Disposal Unit (SDU) referred to as SDU 6. This initial modeling study was intended to assess the performance of major components of the structure that are most significant to the PA. Information provided by the modeling will support the development of a SDU 6 Preliminary Design Model and Recommendation Report to be written by SRR Closure and Waste Disposal Authority. Key inputs and assumptions for the modeling were provided to SRNL in SRR-SPT-2011-00113 (2). A table reiterates the base case and four sensitivity case studies requested in this reference. In general, as shown in Table 4, when compared to Vault 2 Case A, the Base Case SDU 6 design produced higher peak fluxes to the water table during the 10,000 year period of analysis but lower peak fluxes within a 15,000 to 20,000 time frame. SDU 6 will contain approximately ten times the inventory of a single Vault 2 and the SDU 6 footprint is comparable to that of a group of four Vault 2 disposal units. Therefore, the radionuclide flux from SDU 6 and that from a single Vault 2 are not directly comparable. A more direct comparison would be to compare the maximum dose obtained at the 100 m boundary from the seven SDU's that will replace the 64 FDC's analyzed in the 2009 PA. This analysis will be performed in the next set of calculations planned for SDU design evaluation. Aquifer transport and dose calculations were not intended to be part of this initial scoping study. However, results from this study do indicate that replacement of the FDC design with SDU would not yield significantly higher peak doses. If the thickness of the SDU 6 floor is increased, peak doses would not occur during the 10,000 year period of analysis.

  8. On the proper study design applicable to experimental balneology

    NASA Astrophysics Data System (ADS)

    Varga, Csaba

    2016-08-01

    The simple message of this paper is that it is the high time to reevaluate the strategies and optimize the efforts for investigation of thermal (spa) waters. Several articles trying to clear mode of action of medicinal waters have been published up to now. Almost all studies apply the unproven hypothesis, namely the inorganic ingredients are in close connection with healing effects of bathing. Change of paradigm would be highly necessary in this field taking into consideration the presence of several biologically active organic substances in these waters. A successful design for experimental mechanistic studies is approved.

  9. Design studies for the next generation electron ion colliders

    NASA Astrophysics Data System (ADS)

    Sayed, Hisham Kamal; Bogacz, S. A.; Krafft, G.

    2014-04-01

    The next generation Electron Ion Collider (EIC) at Thomas Jefferson National Accelerator Facility (JLAB) utilizes a figure-8 shaped ion and electron rings. EIC has the ability to preserve the ion polarization during acceleration, where the electron ring matches in footprint with a figure-8 ion ring. The electron ring is designed to deliver a highly polarized high luminous electron beam at interaction point (IP). The main challenges of the electron ring design are the chromaticity compensation and maintaining high beam polarization of 70% at all energies 3-11 GeV without introducing transverse orbital coupling before the IP. The very demanding detector design limits the minimum distance between the final focus quadrupole and the interaction point to 3.5 m which results in a large β function inside the final focus quadrupoles leading to increased beam chromaticity. In this paper, we present a novel chromaticity compensation scheme that mitigates IP chromaticity by a compact chromaticity compensation section with multipole magnet components. In addition, a set of spin rotators are utilized to manipulate the polarization vector of the electron beam in order to preserve the beam polarization. The spin rotator solenoids introduce undesired coupling between the horizontal and vertical betatron motion of the beam. We introduce a compact and modular orbit decoupling insert that can fit in the limited space of the straight section in the figure-8 ring. We show a numerical study of the figure-8 ring design with the compact straight section, which includes the interaction region, chromaticity compensation section, and the spin rotators, the figure-8 design performance is evaluated with particle tracking.

  10. Design studies for the next generation electron ion colliders

    SciTech Connect

    Sayed, Hisham Kamal; Bogacz, Slawomir A.; Krafft, Geoffrey A.

    2014-04-01

    The next generation Electron Ion Collider (EIC) at Thomas Jefferson National Accelerator Facility (JLAB) utilizes a figure-8 shaped ion and electron rings. EIC has the ability to preserve the ion polarization during acceleration, where the electron ring matches in footprint with a figure-8 ion ring. The electron ring is designed to deliver a highly polarized high luminous electron beam at interaction point (IP). The main challenges of the electron ring design are the chromaticity compensation and maintaining high beam polarization of 70% at all energies 3–11 GeV without introducing transverse orbital coupling before the IP. The very demanding detector design limits the minimum distance between the final focus quadrupole and the interaction point to 3.5 m which results in a large β function inside the final focus quadrupoles leading to increased beam chromaticity. In this paper, we present a novel chromaticity compensation scheme that mitigates IP chromaticity by a compact chromaticity compensation section with multipole magnet components. In addition, a set of spin rotators are utilized to manipulate the polarization vector of the electron beam in order to preserve the beam polarization. The spin rotator solenoids introduce undesired coupling between the horizontal and vertical betatron motion of the beam. We introduce a compact and modular orbit decoupling insert that can fit in the limited space of the straight section in the figure-8 ring. We show a numerical study of the figure-8 ring design with the compact straight section, which includes the interaction region, chromaticity compensation section, and the spin rotators, the figure-8 design performance is evaluated with particle tracking.

  11. Influence of Study Design Variables on Clinical Pathology Data.

    PubMed

    Aulbach, Adam; Provencher, Anne; Tripathi, Niraj

    2017-02-01

    A number of factors related to study design have the potential to impact clinical pathology test results during the conduct of nonclinical safety studies. A thorough understanding of these factors is paramount in drawing accurate conclusions from clinical pathology data generated during such studies, particularly when attempting to make the distinction between test article and nontest article-related effects. Study design and conduct variables with potential to impact clinical pathology data discussed in this overview include those related to species and test system, animal age, animal care and husbandry practices, fasting, acclimatization periods, effects of transportation and stressors, route of administration, effects of in-life and surgical procedures, influence of study length, timing of blood collections, impact of vehicle/formulation composition, and some general concepts related to drug class. The material presented here is a summary based on information presented at the 35th Annual Symposium of the Society of Toxicologic Pathology (June 2016), during Symposium Session 2 titled "Deciphering Sources of Variability in Clinical Pathology-It's Not Just about the Numbers."

  12. Spherical Cryogenic Hydrogen Tank Preliminary Design Trade Studies

    NASA Technical Reports Server (NTRS)

    Arnold, Steven M.; Bednarcyk, Brett A.; Collier, Craig S.; Yarrington, Phillip W.

    2007-01-01

    A structural analysis, sizing optimization, and weight prediction study was performed by Collier Research Corporation and NASA Glenn on a spherical cryogenic hydrogen tank. The tank consisted of an inner and outer wall separated by a vacuum for thermal insulation purposes. HyperSizer (Collier Research and Development Corporation), a commercial automated structural analysis and sizing software package was used to design the lightest feasible tank for a given overall size and thermomechanical loading environment. Weight trade studies were completed for different panel concepts and metallic and composite material systems. Extensive failure analyses were performed for each combination of dimensional variables, materials, and layups to establish the structural integrity of tank designs. Detailed stress and strain fields were computed from operational temperature changes and pressure loads. The inner tank wall is sized by the resulting biaxial tensile stresses which cause it to be strength driven, and leads to an optimum panel concept that need not be stiffened. Conversely, the outer tank wall is sized by a biaxial compressive stress field, induced by the pressure differential between atmospheric pressure and the vacuum between the tanks, thereby causing the design to be stability driven and thus stiffened to prevent buckling. Induced thermal stresses become a major sizing driver when a composite or hybrid composite/metallic material systems are used for the inner tank wall for purposes such as liners to contain the fuel and reduce hydrogen permeation.

  13. X-33 Base Region Thermal Protection System Design Study

    NASA Technical Reports Server (NTRS)

    Lycans, Randal W.

    1998-01-01

    The X-33 is an advanced technology demonstrator for validating critical technologies and systems required for an operational Single-Stage-to-Orbit (SSTO) Reusuable Launch Vehicle (RLV). Currently under development by a unique contractor/government team led by Lockheed- Martin Skunk Works (LMSW), and managed by Marshall Space Flight Center (MSFC), the X-33 will be the prototype of the first new launch system developed by the United States since the advent of the space shuttle. This paper documents a design trade study of the X-33 base region thermal protection system (TPS). Two candidate designs were evaluated for thermal performance and weight. The first candidate was a fully reusable metallic TPS using Inconel honeycomb panels insulated with high temperature fibrous insulation, while the second was an ablator/insulator sprayed on the metallic skin of the vehicle. The TPS configurations and insulation thickness requirements were determined for the predicted main engine plume heating environments and base region entry aerothermal environments. In addition to thermal analysis of the design concepts, sensitivity studies were performed to investigate the effect of variations in key parameters of the base TPS analysis.

  14. Optimization Studies of the FERMI at ELETTRA FEL Design

    SciTech Connect

    De Ninno, Giovanni; Fawley, William M.; Penn, Gregory E.; Graves,William

    2005-08-25

    The FERMI at ELETTRA project at Sincotrone Trieste involves two FEL's, each based upon the principle of seeded harmonic generation and using the existing ELETTRA injection linac at 1.2 GeV beam energy. Scheduled to be completed in 2008, FEL-1 will operate in 40-100 nm wavelength range and will involve one stage of harmonic up-conversion. The second undulator line, FEL-2, will begin operation two years later in the 10-40 nm wavelength range and use two harmonic stages operating as a cascade. The FEL design assumes continuous wavelength tunability over the full wavelength range, and polarization tunability of the output radiation including vertical or horizontal linear as well as helical polarization. The design considers focusing properties and segmentation of realizable undulators and available input seed lasers. We review the studies that have led to our current design. We present results of simulations using GENESIS and GINGER simulation codes including studies of various shot-to-shot fluctuations and undulator errors. Findings for the expected output radiation in terms of the power, transverse and longitudinal coherence are reported.

  15. [Case-control studies in psychiatry: causality, design and warnings].

    PubMed

    Silva Ayçaguer, L C

    2004-01-01

    This present paper is mainly methodological and has been written with the aim of helping researchers in psychiatry to produce results with higher quality and help readers to have adequate assessment values of others. Brief reflection is made on the most important conditions that must be fulfilled to prove a causality hypothesis, regardless of the investigation design used. However, the main purpose of the text is to examine and illustrate how these conditions work under a case-control study environment. Besides outlining the basic aspects concerning design and analysis, areas extremely illustrated with examples of case and controls in psychiatry found in the literature, a number of suggestions to avoid pitfalls that can invalidate research efforts developed using case-control methodology is offered.

  16. Heat Exchanger Design Studies for AN Lhc Inner Triplet Upgrade

    NASA Astrophysics Data System (ADS)

    Rabehl, R. J.; Huang, Y.

    2008-03-01

    A luminosity upgrade of the CERN Large Hadron Collider (LHC) is planned to coincide with the expected end of life of the existing inner triplet quadrupole magnets. The upgraded inner triplet will have much larger heat loads to be removed from the magnets by the cryogenics system. A number of cryogenics design studies have been completed under the LHC Accelerator Research Program (LARP), including investigations of required heat exchanger characteristics to transfer this heat from the pressurized He II bath to the saturated He II system. This paper discusses heat exchangers both external to the magnet cold mass and internal to the magnet cold mass. A possible design for a heat exchanger external to the magnet cold mass is also presented.

  17. Study design in evidence-based surgery: What is the role of case-control studies?

    PubMed Central

    Cao, Amy M; Cox, Michael R; Eslick, Guy D

    2016-01-01

    Randomized controlled trials (RCTs) are the gold standard in terms of study design, however, in the surgical setting conducting RCTs can often be unethical or logistically impossible. Case-control studies should become the major study design used in surgical research when RCTs are unable to be conducted and definitely replacing case series which offer little insight into surgical outcomes and disease processes. PMID:27019801

  18. Interim Design Report for the International Design Study for a Neutrino Factory

    SciTech Connect

    Choubey, S.; Gandhi, R.; Goswami, S.; Berg, J.S.; Fernow, R.; Gallardo, J.C.; Gupta, R.; Kirk, H.; Simos, N.; Souchlas, N.; Ellis, M.; /Brunel U. /CERN /Durham U., IPPP /Fermilab /Geneva U. /Glasgow U. /Heidelberg, Max Planck Inst. /Imperial Coll., London /Jefferson Lab /Saha Inst.

    2011-10-01

    The starting point for the International Design Study for the Neutrino Factory (the IDS-NF) was the output of the earlier International Scoping Study for a future Neutrino Factory and super-beam facility (the ISS). The accelerator facility described in section 2 incorporates the improvements that have been derived from the substantial amount of work carried out within the Accelerator Working Group. Highlights of these improvements include: (1) Initial concepts for the implementation of the proton driver at each of the three example sites, CERN, FNAL, and RAL; (2) Detailed studies of the energy deposition in the target area; (3) A reduction in the length of the muon beam phase-rotation and bunching systems; (4) Detailed analyses of the impact of the risk that stray magnetic field in the accelerating cavities in the ionization cooling channel will reduce the maximum operating gradient. Several alternative ionization-cooling lattices have been developed as fallback options to mitigate this technical risk; (5) Studies of particle loss in the muon front-end and the development of strategies to mitigate the deleterious effects of such losses; (6) The development of more complete designs for the muon linac and re-circulating linacs; (7) The development of a design for the muon FFAG that incorporates insertions for injection and extraction; and (8) Detailed studies of diagnostics in the decay ring. Other sub-systems have undergone a more 'incremental' evolution; an indication that the design of the Neutrino Factory has achieved a degree of maturity. The design of the neutrino detectors described in section 3 has been optimized and the Detector Working Group has made substantial improvements to the simulation and analysis of the Magnetized Iron Neutrino Detector (MIND) resulting in an improvement in the overall neutrino-detection efficiency and a reduction in the neutrino-energy threshold. In addition, initial consideration of the engineering of the MIND has generated a

  19. Optimal study design for pioglitazone in septic pediatric patients.

    PubMed

    Sherwin, Catherine M T; Ding, Lili; Kaplan, Jennifer; Spigarelli, Michael G; Vinks, Alexander A

    2011-08-01

    The objective was to demonstrate the methodology and process of optimal sparse sampling pharmacokinetics (PK). This utilized a single daily dose of pioglitazone for pediatric patients with severe sepsis and septic shock based upon adult and minimal adolescent data. Pioglitazone pharmacokinetics were modeled using non-compartment analysis WinNonlin Pro (version 5.1) and population kinetics using NONMEM (version 7.1) with first order conditional estimation method (FOCE) with interaction. The initial model was generated from single- and multiple-dose pioglitazone PK data (15 mg, 30 mg, and 45 mg) in 36 adolescents with diabetes. PK models were simulated and overlaid upon original data to provide a comparison best described by a single compartment, first order model. The optimal design was based on the simulated oral administration of pioglitazone to three groups of pediatric patients, age 3.8 (2-6 years), weight 14.4 (7-28 kg); age 9.6 (6.1-11.9 years), weight 36.5 (28.1-48 kg) and age 15.5 (12-17 years,) weight 61.6 (48.1-80 kg). PFIM (version 3.2) was used to evaluate sample study size. Datasets were compiled using simulation for each dose (15, 30 and 45 mg) for the potential age/weight groups. A target dose of 15 mg daily in the youngest and middle groups was considered appropriate with area under the curve exposure levels (AUC) comparable to studies in adolescents. The final optimal design suggested time points of 0.5, 2, 6 and 21 h for 24 h dosing. This methodology provides a robust method of utilizing adult and limited adolescent data to simulate allometrically scaled, pediatric data sets that allow the optimal design of a pediatric trial. The pharmacokinetics of pioglitazone were described adequately and simulated data estimates were comparable to literature values. The optimal design provided clinically attainable sample times and windows.

  20. Solar-Powered Europa Orbiter Design Study (2007)

    NASA Technical Reports Server (NTRS)

    Elliott, John; Langmaier, Jerry; Pappalardo, Robert; Strange, Nathan; Spilker, Tom; Lock, Rob; Reh, Kim

    2008-01-01

    The feasibility of implementing a solar-powered mission around Europa has been evaluated periodically over the last decade. Most recently, an assessment was performed as part of the 2006 Europa Explorer (EE) Study, which evaluated the practicality of implementing that mission design with large solar arrays instead of radioisotope power systems (RPS). This previous study went into some depth in considering the issues related to the use of solar arrays in the Europa orbit illumination and radiation environment. The study concluded that an all-solar option was impractical to meet the science objectives as defined in that study by the science team. This conclusion resulted from the prohibitive mass, packaging and articulation issues associated with the very large (approx.300 sq m) solar arrays required to accommodate frequent eclipse periods associated with the particular Europa orbit used.

  1. Vaccine stability study design and analysis to support product licensure.

    PubMed

    Schofield, Timothy L

    2009-11-01

    Stability evaluation supporting vaccine licensure includes studies of bulk intermediates as well as final container product. Long-term and accelerated studies are performed to support shelf life and to determine release limits for the vaccine. Vaccine shelf life is best determined utilizing a formal statistical evaluation outlined in the ICH guidelines, while minimum release is calculated to help assure adequate potency through handling and storage of the vaccine. In addition to supporting release potency determination, accelerated stability studies may be used to support a strategy to recalculate product expiry after an unintended temperature excursion such as a cold storage unit failure or mishandling during transport. Appropriate statistical evaluation of vaccine stability data promotes strategic stability study design, in order to reduce the uncertainty associated with the determination of the degradation rate, and the associated risk to the customer.

  2. Design study of fiber-composite penetrator cases

    SciTech Connect

    Logan, R.W.; Groves, S.E.; Lyon, R.E.

    1993-10-22

    A design study was conducted to demonstrate the viability of carbon-fiber reinforced epoxy composites as structural case materials for penetrating warheads. The objective was to conduct well-instrumented experimental studies of composite-body penetrators perforating mild steel plates and quantitatively model these plate penetrations using two- and three-dimensional finite element codes over a wide range of velocities and impact conditions in order to develop predictive capability for composite design and for use in tradeoff studies with existing case materials. Understanding of the failure of composite-body penetrators would be demonstrated by a rational design iteration which significantly improved performance. Initial studies utilized existing 1-degree tapered cylindrical carbon fiber/epoxy composite cases fabricated by wet-filament winding. These sharp-tipped, steel-nose, composite penetrators were strain-gaged, piggy-backed with 57 kilograms, and impacted into steel plates in a velocity-boosted droptower at impact velocities ranging from 3 to 18 meters per second. Load, time, and position data were recorded during the impact event as well as the axial and hoop strains in the composite case. Monolithic 4340 hardened steel penetrators with both sharp- and flat-tip 3-caliber ogive noses were also impacted into mild steel plates. Data from the composite-case and steel penetrators were used to calibrate a multiaxial, rate-dependent, flow and failure model for the mild steel plates in NIKE2D. The authors were then able to successfully predict survival and failure of the composite-case penetrators in normal-incidence droptower tests for different target thickness and velocity combinations.

  3. Preliminary Systems Design Study assessment report. Volume 8, Appendixes

    SciTech Connect

    Mayberry, J.L.; Feizollahi, F.; Del Signore, J.C.

    1992-01-01

    The System Design Study (SDS), part of the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examined techniques available for the remediation of hazardous and transuranic waste stored at the Radioactive Waste Management Complex`s Subsurface Disposal Area at the INEL. Using specific technologies, system concepts for treating the buried waste and the surrounding contaminated soil were evaluated. Evaluation included implementability, effectiveness, and cost. The SDS resulted in the development of technology requirements including demonstration, testing, and evaluation activities needed for implementing each concept. This volume of the Systems Design Study contain four Appendixes that were part of the study. Appendix A is an EG&G Idaho, Inc., report that represents a review and compilation of previous reports describing the wastes and quantities disposed in the Subsurface Disposal Area of the Idaho National Engineering Laboratory. Appendix B contains the process flowsheets considered in this study, but not selected for detailed analysis. Appendix C is a historical tabulation of radioactive waste incinerators. Appendix D lists Department of Energy facilities where cementation stabilization systems have been used.

  4. Accelerating Vaccine Formulation Development Using Design of Experiment Stability Studies.

    PubMed

    Ahl, Patrick L; Mensch, Christopher; Hu, Binghua; Pixley, Heidi; Zhang, Lan; Dieter, Lance; Russell, Ryann; Smith, William J; Przysiecki, Craig; Kosinski, Mike; Blue, Jeffrey T

    2016-10-01

    Vaccine drug product thermal stability often depends on formulation input factors and how they interact. Scientific understanding and professional experience typically allows vaccine formulators to accurately predict the thermal stability output based on formulation input factors such as pH, ionic strength, and excipients. Thermal stability predictions, however, are not enough for regulators. Stability claims must be supported by experimental data. The Quality by Design approach of Design of Experiment (DoE) is well suited to describe formulation outputs such as thermal stability in terms of formulation input factors. A DoE approach particularly at elevated temperatures that induce accelerated degradation can provide empirical understanding of how vaccine formulation input factors and interactions affect vaccine stability output performance. This is possible even when clear scientific understanding of particular formulation stability mechanisms are lacking. A DoE approach was used in an accelerated 37(°)C stability study of an aluminum adjuvant Neisseria meningitidis serogroup B vaccine. Formulation stability differences were identified after only 15 days into the study. We believe this study demonstrates the power of combining DoE methodology with accelerated stress stability studies to accelerate and improve vaccine formulation development programs particularly during the preformulation stage.

  5. Inflammation and Exercise (INFLAME): study rationale, design, and methods

    PubMed Central

    Thompson, Angela; Mikus, Catherine; Rodarte, Ruben Q.; Distefano, Brandy; Priest, Elisa L.; Sinclair, Erin; Earnest, Conrad P.; Blair, Steven N.; Church, Timothy S.

    2008-01-01

    Purpose The INFLAME study is designed to determine the effect of exercise training on elevated high-sensitivity C-Reactive Protein (CRP) concentrations in initially sedentary women and men. Methods INFLAME will recruit 170 healthy, sedentary women and men with elevated CRP (≥2.0 mg/L) to be randomized to either an exercise group or non-exercise control group. Exercising individuals will participate in four months of supervised aerobic exercise with a total energy expenditure of 16 kcal • kg−1 • week−1 (KKW). Exercise intensity will be 60–80% of maximal oxygen consumption (VO2 max). Outcome The primary outcome will be change in plasma CRP concentration. Secondary outcomes include visceral adiposity, the cytokines IL-6 and TNF-α, and heart rate variability (HRV) in order to examine potential biological mechanisms whereby exercise might affect CRP concentrations. Summary INFLAME will help us understand the effects of moderate to vigorous exercise on CRP concentrations in sedentary individuals. To our knowledge this will be the largest training study specifically designed to examine the effect of exercise on CRP concentrations. This study has the potential to influence therapeutic applications since CRP measurement is becoming an important clinical measurement in Coronary Heart Disease risk assessment. This study will also contribute to the limited body of literature examining the effect of exercise on the variables of visceral adiposity, cytokines, and heart rate variability. PMID:18024231

  6. Status of PEP-X Light Source Design Study

    SciTech Connect

    Bane, K.L.F.; Bertsche, K.J.; Cai, Y.; Chao, A.; Huang, X.; Jiao, Y.; Ng, C.-K.; Nosochkov, Y.; Novokhatski, A.; Rivetta, C.H.; Safranek, J.A.; Stupakov, G.V.; Wang, L.; Wang, M.-H.; Xiao, L.; Hettel, R.O.; Rabedeau, T.; /SLAC

    2011-12-14

    The SLAC Beam Physics group and other SLAC collaborators continue to study options for implementing a near diffraction-limited ring-based light source in the 2.2-km PEP-II tunnel that will serve the SSRL scientific program in the future. The study team has completed the baseline design for a 4.5-GeV storage ring having 160 pm-rad emittance with stored beam current of 1.5 A, providing >10{sup 22} brightness for multi-keV photon beams from 3.5-m undulator sources. The team has also investigated possible 5-GeV ERL configurations which, similar to the Cornell and KEK ERL plans, would have {approx}30 pm-rad emittance with 100 mA current, and {approx}10 pm-rad emittance with 25 mA or less. Now a 4.5-GeV 'ultimate' storage ring having emittance similar to the ERL and operating with {approx}200 mA is under study. An overview of the progress of the PEP-X design study and SSRL's plans for defining performance parameters that will guide the choice of ring options is presented.

  7. Applying Semiotic Theories to Graphic Design Education: An Empirical Study on Poster Design Teaching

    ERIC Educational Resources Information Center

    Yang, Chao-Ming; Hsu, Tzu-Fan

    2015-01-01

    The rationales behind design are dissimilar to those behind art. Establishing an adequate theoretical foundation for conducting design education can facilitate scientising design methods. Thus, from the perspectives of the semiotic theories proposed by Saussure and Peirce, we investigated graphic design curricula by performing teaching…

  8. Destined to Design? How and Why Australian Women Choose to Study Industrial Design

    ERIC Educational Resources Information Center

    Lockhart, Cathy; Miller, Evonne

    2016-01-01

    Despite over three decades of legislation and initiatives designed to tackle the traditional gender divide in the science, technology and design fields, only a quarter of the registered architects in Australia are women. There are no statistics available for other design disciplines, with little known about why women choose design as a career path…

  9. Topics in Study Design and Analysis for Multistage Clinical Proteomics Studies.

    PubMed

    Zeng, Irene Sui Lan

    2016-01-01

    This chapter discusses the design issues in clinical proteomics study and provides specific suggestions for addressing these questions when using the standard guidelines for the planning. It provides two methods for the sample size estimation in study design. The first method is used for the planning of a clinical proteomic study at the discovery or verification stage; the second method is proposed for the systematic planning of a multistage study. The second part of the chapter introduces three approaches to analyzing the clinical proteomic study and provides analyses for two case studies of clinical proteomic discoveries.

  10. Design study of a high power rotary transformer

    NASA Technical Reports Server (NTRS)

    Weinberger, S. M.

    1982-01-01

    A design study was made on a rotary transformer for transferring electrical power across a rotating spacecraft interface. The analysis was performed for a 100 KW, 20 KHz unit having a ""pancake'' geometry. The rotary transformer had a radial (vertical) gap and consisted of 4-25 KW modules. It was assumed that the power conditioning comprised of a Schwarz resonant circuit with a 20 KHz switching frequency. The rotary transformer, mechanical and structural design, heat rejection system and drive mechanism which provide a complete power transfer device were examined. The rotary transformer losses, efficiency, weight and size were compared with an axial (axial symmetric) gap transformer having the same performance requirements and input characteristics which was designed as part of a previous program. The ""pancake'' geometry results in a heavier rotary transformer primarily because of inefficient use of the core material. It is shown that the radial gap rotary transformer is a feasible approach for the transfer of electrical power across a rotating interface and can be implemented using presently available technology.

  11. Theoretical design study of the MSFC wind-wheel turbine

    NASA Technical Reports Server (NTRS)

    Frost, W.; Kessel, P. A.

    1982-01-01

    A wind wheel turbine (WWT) is studied. Evaluation of the probable performance, possible practical applications, and economic viability as compared to other conventional wind energy systems is discussed. The WWT apparatus is essentially a bladed wheel which is directly exposed to the wind on the upper half and exposed to wind through multiple ducting on the lower half. The multiple ducts consist of a forward duct (front concentrator) and two side ducts (side concentrators). The forced rotation of the wheel is then converted to power through appropriate subsystems. Test results on two simple models, a paper model and a stainless steel model, are reported. Measured values of power coefficients over wind speeds ranging from 4 to 16 m/s are given. An analytical model of a four bladed wheel is also developed. Overall design features of the wind turbine are evaluated and discussed. Turbine sizing is specified for a 5 and 25 kW machine. Suggested improvements to the original design to increase performance and performance predictions for an improved WWT design are given.

  12. Titanium-doped sapphire laser research and design study

    NASA Technical Reports Server (NTRS)

    Moulton, Peter F.

    1987-01-01

    Three main topics were considered in this study: the fundamental laser parameters of titanium-doped sapphire, characterization of commercially grown material, and design of a tunable, narrow-linewidth laser. Fundamental parameters investigated included the gain cross section, upper-state lifetime as a function of temperature and the surface-damage threshold. Commercial material was found to vary widely in the level of absorption of the laser wavelength with the highest absorption in Czochralski-grown crystals. Several Yi:sapphire lasers were constructed, including a multimode laser with greater than 50mJ of output energy and a single-transverse-mode ring laser, whose spectral and temporal characteristics were completely characterized. A design for a narrow-linewidth (single-frequency) Ti:sapphire laser was developed, based on the results of the experimental work. The design involves the use of a single-frequency, quasi-cw master oscillator, employed as an injection source for a pulsed ring laser.

  13. Design Study for a Global Magnetospheric Dynamics Mission

    NASA Technical Reports Server (NTRS)

    Russell, C. T.

    1999-01-01

    A successful design was developed, one with many advantages over the original mission. The time spent in orbit was more evenly spread over the region being investigated. The radiation close was significantly lower and the mission did not rely on gravity assist at the moon and thus did not have to make measurements that far out in the tail. A spacecraft design was developed that keeps interference from the engines to a minimum. The design however was quite specific for four spacecraft. It could not be easily scaled to five spacecraft for example. One problem was discovered that is a concern for all similar missions. Inter- spacecraft communication can determine the spacing of the vehicles easily and to the accuracy required. However, the orientation of the polyhedron with the spacecraft at its vertices is not well known for small separations. Ground station range measurements give the line of sight location well but not the angle around that vector. This is a problem any such mission needs to solve. Neither the navigation teams at Goddard nor at Lewis were willing to attempt to solve this problem. At the completion of the study a report was made to the AGU meeting in San Francisco and a paper published in the volume "Science Closure and Enabling Technologies for Constellation Class Missions". This paper is attached.

  14. Lessons learned studying design issues for lunar and Mars settlements

    NASA Technical Reports Server (NTRS)

    Litton, C. E.

    1997-01-01

    In a study of lunar and Mars settlement concepts, an analysis was made of fundamental design assumptions in five technical areas against a model list of occupational and environmental health concerns. The technical areas included the proposed science projects to be supported, habitat and construction issues, closed ecosystem issues, the "MMM" issues (mining, material processing, and manufacturing), and the human elements of physiology, behavior, and mission approach. Four major lessons were learned. First it is possible to relate public health concerns to complex technological development in a proactive design mode, which has the potential for long-term cost savings. Second, it became very apparent that prior to committing any nation or international group to spending the billions to start and complete a lunar settlement, over the next century, that a significantly different approach must be taken from those previously proposed, to solve the closed ecosystem and "MMM" problems. Third, it also appears that the health concerns and technology issues to be addressed for human exploration into space are fundamentally those to be solved for human habitation of the Earth (as a closed ecosystem) in the 21st century. Finally, it is proposed that ecosystem design modeling must develop new tools, based on probabilistic models as a step up from closed circuit models.

  15. Biomimetic design of a brush-like nanopore: simulation studies.

    PubMed

    Pongprayoon, Prapasiri; Beckstein, Oliver; Sansom, Mark S P

    2012-01-12

    Combining a high degree of selectivity and nanoscale dimensions, biological pores are attractive potential components for nanotechnology devices and applications. Biomimetic design will facilitate production of stable synthetic nanopores with defined functionality. Bacterial porins offer a good source of possible templates for such nanopores as they form stable, selective pores in lipid bilayers. Molecular dynamics simulations have been used to design simple model nanopores with permeation free energy profiles that can be made to mimic a template protein, the OprP porin, which forms pores selective for anions. In particular, we explored the effects of varying the nature of pore-lining groups on free energy profiles for phosphate and chloride ions along the pore axis and the total charge of the permeation pathway of the pore. Cationic side chains lining the model nanopore are required to model the local detail of the OprP permeation landscape, whereas the total charge contributes to its magnitude. These studies indicate that a locally accurate biomimetic design has captured the essentials of the structure/function relationship of the parent protein.

  16. Lessons learned studying design issues for lunar and Mars settlements.

    PubMed

    Litton, C E

    1997-01-01

    In a study of lunar and Mars settlement concepts, an analysis was made of fundamental design assumptions in five technical areas against a model list of occupational and environmental health concerns. The technical areas included the proposed science projects to be supported, habitat and construction issues, closed ecosystem issues, the "MMM" issues (mining, material processing, and manufacturing), and the human elements of physiology, behavior, and mission approach. Four major lessons were learned. First it is possible to relate public health concerns to complex technological development in a proactive design mode, which has the potential for long-term cost savings. Second, it became very apparent that prior to committing any nation or international group to spending the billions to start and complete a lunar settlement, over the next century, that a significantly different approach must be taken from those previously proposed, to solve the closed ecosystem and "MMM" problems. Third, it also appears that the health concerns and technology issues to be addressed for human exploration into space are fundamentally those to be solved for human habitation of the Earth (as a closed ecosystem) in the 21st century. Finally, it is proposed that ecosystem design modeling must develop new tools, based on probabilistic models as a step up from closed circuit models.

  17. Conceptual design study of an improved automotive gas turbine powertrain

    NASA Technical Reports Server (NTRS)

    Wagner, C. E. (Editor); Pampreen, R. C. (Editor)

    1979-01-01

    Automotive gas turbine concepts with significant technological advantages over the spark ignition (SI) engine were assessed. Possible design concepts were rated with respect to fuel economy and near-term application. A program plan which outlines the development of the improved gas turbine (IGT) concept that best met the goals and objectives of the study identifies the research and development work needed to meet the goal of entering a production engineering phase by 1983. The fuel economy goal is to show at least a 20% improvement over a conventional 1976 SI engine/vehicle system. On the basis of achieving the fuel economy goal, of overall suitability to mechanical design, and of automotive mass production cost, the powertrain selected was a single-shaft engine with a radial turbine and a continuously variable transmission (CVT). Design turbine inlet temperature was 1150 C. Reflecting near-term technology, the turbine rotor would be made of an advanced superalloy, and the transmission would be a hydromechanical CVT. With successful progress in long-lead R&D in ceramic technology and the belt-drive CVT, the turbine inlet temperature would be 1350 C to achieve near-maximum fuel economy.

  18. The Study of the Relationship between Probabilistic Design and Axiomatic Design Methodology. Volume 3

    NASA Technical Reports Server (NTRS)

    Onwubiko, Chin-Yere; Onyebueke, Landon

    1996-01-01

    Structural failure is rarely a "sudden death" type of event, such sudden failures may occur only under abnormal loadings like bomb or gas explosions and very strong earthquakes. In most cases, structures fail due to damage accumulated under normal loadings such as wind loads, dead and live loads. The consequence of cumulative damage will affect the reliability of surviving components and finally causes collapse of the system. The cumulative damage effects on system reliability under time-invariant loadings are of practical interest in structural design and therefore will be investigated in this study. The scope of this study is, however, restricted to the consideration of damage accumulation as the increase in the number of failed components due to the violation of their strength limits.

  19. Study of unconventional aircraft engines designed for low energy consumption

    NASA Technical Reports Server (NTRS)

    Neitzel, R. E.; Hirschkron, R.; Johnston, R. P.

    1976-01-01

    A study of unconventional engine cycle concepts, which may offer significantly lower energy consumption than conventional subsonic transport turbofans, is described herein. A number of unconventional engine concepts were identified and parametrically studied to determine their relative fuel-saving potential. Based on results from these studies, regenerative, geared, and variable-boost turbofans, and combinations thereof, were selected along with advanced turboprop cycles for further evaluation and refinement. Preliminary aerodynamic and mechanical designs of these unconventional engine configurations were conducted and mission performance was compared to a conventional, direct-drive turofan reference engine. Consideration is given to the unconventional concepts, and their state of readiness for application. Areas of needed technology advancement are identified.

  20. Family-based designs for genome-wide association studies.

    PubMed

    Ott, Jurg; Kamatani, Yoichiro; Lathrop, Mark

    2011-06-01

    Association mapping has successfully identified common SNPs associated with many diseases. However, the inability of this class of variation to account for most of the supposed heritability has led to a renewed interest in methods - primarily linkage analysis - to detect rare variants. Family designs allow for control of population stratification, investigations of questions such as parent-of-origin effects and other applications that are imperfectly or not readily addressed in case-control association studies. This article guides readers through the interface between linkage and association analysis, reviews the new methodologies and provides useful guidelines for applications. Just as effective SNP-genotyping tools helped to realize the potential of association studies, next-generation sequencing tools will benefit genetic studies by improving the power of family-based approaches.

  1. Residuals and outliers in replicate design crossover studies.

    PubMed

    Schall, Robert; Endrenyi, Laszlo; Ring, Arne

    2010-07-01

    Outliers in bioequivalence trials may arise through various mechanisms, requiring different interpretation and handling of such data points. For example, regulatory authorities might permit exclusion from analysis of outliers caused by product or process failure, while exclusion of outliers caused by subject-by-treatment interaction generally is not acceptable. In standard 2 x 2 crossover studies it is not possible to distinguish between relevant types of outliers based on statistical criteria alone. However, in replicate design (2-treatment, 4-period) crossover studies three types of outliers can be distinguished: (i) Subject outliers are usually unproblematic, at least regarding the analysis of bioequivalence, and may require no further action; (ii) Subject-by-formulation outliers may affect the outcome of the bioequivalence test but generally cannot simply be removed from analysis; and (iii) Removal of single-data-point outliers from analysis may be justified in certain cases. As a very simple but effective diagnostic tool for the identification and classification of outliers in replicate design crossover studies we propose to calculate and plot three types of residual corresponding to the three different types of outliers that can be distinguished. The residuals are obtained from four mutually orthogonal linear contrasts of the four data points associated with each subject. If preferred, outlier tests can be applied to the resulting sets of residuals after suitable standardization.

  2. RHQT Nb3Al 15-Tesla magnet design study

    SciTech Connect

    Yamada, R.; Ambrosio, G.; Barzi, E.; Kashikin, V.; Kikuchi, A.; Novitski, I.; Takeuchi, T.; Wake, M.; Zlobin, A.; /Fermilab /NIMC, Tsukuba /KEK, Tsukuba

    2005-09-01

    Feasibility study of 15-Tesla dipole magnets wound with a new copper stabilized RHQT Nb{sub 3}Al Rutherford cable is presented. A new practical long copper stabilized RHQT Nb{sub 3}Al strand is presented, which is being developed and manufactured at the National Institute of Material Science (NIMS) in Japan. It has achieved a non-copper J{sub c} of 1000A/mm{sup 2} at 15 Tesla at 4.2K, with a copper over non-copper ratio of 1.04, and a filament size less than 50 microns. For this design study a short Rutherford cable with 28 Nb{sub 3}Al strands of 1 mm diameter will be fabricated late this year. The cosine theta magnet cross section is designed using ROXIE, and the stress and strain in the coil is estimated and studied with the characteristics of the Nb{sub 3}Al strand. The advantages and disadvantages of the Nb{sub 3}Al cable are compared with the prevailing Nb{sub 3}Sn cable from the point of view of stress-strain, J{sub c}, and possible degradation of stabilizer due to cabling. The Nb{sub 3}Al coil of the magnet, which will be made by wind and react method, has to be heat treated at 800 degree C for 10 hours. As preparation for the 15 Tesla magnet, a series of tests on strand and Rutherford cables are considered.

  3. High flux isotope reactor cold source preconceptual design study report

    SciTech Connect

    Selby, D.L.; Bucholz, J.A.; Burnette, S.E.

    1995-12-01

    In February 1995, the deputy director of Oak Ridge National Laboratory (ORNL) 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. The anticipated cold source will consist of a cryogenic LH{sub 2} moderator plug, a cryogenic pump system, a refrigerator that uses helium gas as a refrigerant, a heat exchanger to interface the refrigerant with the hydrogen loop, liquid hydrogen transfer lines, a gas handling system that includes vacuum lines, and an instrumentation and control system to provide constant system status monitoring and to maintain system stability. The scope of this project includes the development, design, safety analysis, procurement/fabrication, testing, and installation of all of the components necessary to produce a working cold source within an existing HFIR beam tube. This project will also include those activities necessary to transport the cold neutron beam to the front face of the present HFIR beam room. The cold source project has been divided into four phases: (1) preconceptual, (2) conceptual design and research and development (R and D), (3) detailed design and procurement, and (4) installation and operation. This report marks the conclusion of the preconceptual phase and establishes the concept feasibility. The information presented includes the project scope, the preliminary design requirements, the preliminary cost and schedule, the preliminary performance data, and an outline of the various plans for completing the project.

  4. Shuttle Global Positioning System (GPS) system design study

    NASA Technical Reports Server (NTRS)

    Nilsen, P. W.

    1979-01-01

    The various integration problems in the Shuttle GPS system were investigated. The analysis of the Shuttle GPS link was studied. A preamplifier was designed since the Shuttle GPS antennas must be located remotely from the receiver. Several GPS receiver architecture trade-offs were discussed. The Shuttle RF harmonics and intermode that fall within the GPS receiver bandwidth were analyzed. The GPS PN code acquisition was examined. Since the receiver clock strongly affects both GPS carrier and code acquisition performance, a clock model was developed.

  5. Alpha low-level stored waste systems design study

    SciTech Connect

    Feizollahi, F.; Teheranian, B. . Environmental Services Div.); Quapp, W.J. )

    1992-08-01

    The Stored Waste System Design Study (SWSDS), commissioned by the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examines relative life-cycle costs associated with three system concepts for processing the alpha low-level waste (alpha-LLW) stored at the Radioactive Waste Management Complex's Transuranic Storage Area at the INEL. The three system concepts are incineration/melting; thermal treatment/solidification; and sort, treat, and repackage. The SWSDS identifies system functional and operational requirements and assesses implementability; effectiveness; cost; and demonstration, testing, and evaluation (DT E) requirements for each of the three concepts.

  6. Alpha low-level stored waste systems design study

    SciTech Connect

    Feizollahi, F.; Teheranian, B.; Quapp, W.J.

    1992-08-01

    The Stored Waste System Design Study (SWSDS), commissioned by the Waste Technology Development Department at the Idaho National Engineering Laboratory (INEL), examines relative life-cycle costs associated with three system concepts for processing the alpha low-level waste (alpha-LLW) stored at the Radioactive Waste Management Complex`s Transuranic Storage Area at the INEL. The three system concepts are incineration/melting; thermal treatment/solidification; and sort, treat, and repackage. The SWSDS identifies system functional and operational requirements and assesses implementability; effectiveness; cost; and demonstration, testing, and evaluation (DT&E) requirements for each of the three concepts.

  7. Advanced vehicle concepts systems and design analysis studies

    NASA Technical Reports Server (NTRS)

    Waters, Mark H.; Huynh, Loc C.

    1994-01-01

    The work conducted by the ELORET Institute under this Cooperative Agreement includes the modeling of hypersonic propulsion systems and the evaluation of hypersonic vehicles in general and most recently hypersonic waverider vehicles. This work in hypersonics was applied to the design of a two-stage to orbit launch vehicle which was included in the NASA Access to Space Project. Additional research regarded the Oblique All-Wing (OAW) Project at NASA ARC and included detailed configuration studies of OAW transport aircraft. Finally, work on the modeling of subsonic and supersonic turbofan engines was conducted under this research program.

  8. Study of orbit correction for eRHIC FFAG design

    SciTech Connect

    Liu, C.; Hao, Y.; Litvinenko, V.; Meot, F.; Minty, M.; Ptitsyn, V.; Trbojevic, D.

    2015-05-03

    The unique feature of the orbits in the eRHIC Fixed Field Alternating Gradient (FFAG) design is that multiple accelerating and decelerating bunches pass through the same magnets with different horizontal offsets. Therefore, it is critical for the eRHIC FFAG to correct multiple orbits in the same vacuum pipe for better spin transmission and alignment of colliding beams. In this report, the effects on orbits from multiple error sources will be studied. The orbit correction method will be described and results will be presented.

  9. Designing artificial enzymes from scratch: Experimental study and mesoscale simulation

    NASA Astrophysics Data System (ADS)

    Komarov, Pavel V.; Zaborina, Olga E.; Klimova, Tamara P.; Lozinsky, Vladimir I.; Khalatur, Pavel G.; Khokhlov, Alexey R.

    2016-09-01

    We present a new concept for designing biomimetic analogs of enzymatic proteins; these analogs are based on the synthetic protein-like copolymers. α-Chymotrypsin is used as a prototype of the artificial catalyst. Our experimental study shows that in the course of free radical copolymerization of hydrophobic and hydrophilic monomers the target globular nanostructures of a "core-shell" morphology appear in a selective solvent. Using a mesoscale computer simulation, we show that the protein-like globules can have a large number of catalytic centers located at the hydrophobic core/hydrophilic shell interface.

  10. Integrated learning in practical machine element design course: a case study of V-pulley design

    NASA Astrophysics Data System (ADS)

    Tantrabandit, Manop

    2014-06-01

    To achieve an effective integrated learning in Machine Element Design course, it is of importance to bridge the basic knowledge and skills of element designs. The multiple core learning leads the pathway which consists of two main parts. The first part involves teaching documents of which the contents are number of V-groove formulae, standard of V-grooved pulleys, and parallel key dimension's formulae. The second part relates to the subjects that the students have studied prior to participating in this integrated learning course, namely Material Selection, Manufacturing Process, Applied Engineering Drawing, CAD (Computer Aided Design) animation software. Moreover, an intensive cooperation between a lecturer and students is another key factor to fulfill the success of integrated learning. Last but not least, the students need to share their knowledge within the group and among the other groups aiming to gain knowledge of and skills in 1) the application of CAD-software to build up manufacture part drawings, 2) assembly drawing, 3) simulation to verify the strength of loaded pulley by method of Finite Element Analysis (FEA), 4) the software to create animation of mounting and dismounting of a pulley to a shaft, and 5) an instruction manual. The end product of this integrated learning, as a result of the above 1 to 5 knowledge and skills obtained, the participating students can create an assembly derived from manufacture part drawings and a video presentation with bilingual (English-Thai) audio description of Vpulley with datum diameter of 250 mm, 4 grooves, and type of groove: SPA.

  11. Variability and impact on design of bioequivalence studies.

    PubMed

    Van Peer, Achiel

    2010-03-01

    In 2008, the European Agency for the Evaluation of Medicinal Products released a draft guidance on the investigation of bioequivalence for immediate release dosage forms with systemic action to replace the former guidance of a decade ago. Revisions of the regulatory guidance are based upon many questions over the past years and sometimes continuing scientific discussions on the use of the most suitable statistical analysis methods and study designs, particularly for drugs and drug products with high within-subject variability. Although high within-subject variability is usually associated with a coefficient of variation of 30% or more, new approaches are available in the literature to allow a gradual increase and a levelling off of the bioequivalence limits to some maximum wider values (e.g. 75-133%), dependent on the increase in the within-subject variability. The two-way, cross-over single dose study measuring parent drug is still the design of first choice. A partial replicate design with repeating the reference product and scaling the bioequivalence for the reference variability are proposed for drugs with high within-subject variability. In case of high variability, more regulatory authorities may accept a two-stage or group-sequential bioequivalence design using appropriately adjusted statistical analysis. This review also considers the mechanisms why drugs and drug products may exhibit large variability. The physiological complexity of the gastrointestinal tract and the interaction with the physicochemical properties of drug substances may contribute to the variation in plasma drug concentration-time profiles of drugs and drug products and to variability between and within subjects. A review of submitted bioequivalence studies at the Food and Drug Administration's Office of Generic Drugs over the period 2003-2005 indicated that extensive pre-systemic metabolism of the drug substance was the most important explanation for consistently high variability drugs

  12. Objectives and Design of the Hemodialysis Fistula Maturation Study

    PubMed Central

    Dember, Laura M.; Imrey, Peter B.; Beck, Gerald J.; Cheung, Alfred K.; Himmelfarb, Jonathan; Huber, Thomas S.; Kusek, John W.; Roy-Chaudhury, Prabir; Vazquez, Miguel A.; Alpers, Charles E.; Robbin, Michelle L.; Vita, Joseph A.; Greene, Tom; Gassman, Jennifer J.; Feldman, Harold I.

    2014-01-01

    Background A large proportion of newly created arteriovenous fistulas cannot be used for dialysis because they fail to mature adequately to support the hemodialysis blood circuit. The Hemodialysis Fistula Maturation (HFM) Study was designed to elucidate clinical and biological factors associated with fistula maturation outcomes. Study Design Multicenter prospective cohort study. Setting & Participants Approximately 600 patients undergoing creation of a new hemodialysis fistula will be enrolled at 7 centers in the United States and followed up for as long as 4 years. Predictors Clinical, anatomical, biological, and process-of-care attributes identified pre-operatively, intra-operatively, or post-operatively. Outcomes The primary outcome is unassisted clinical maturation defined as successful use of the fistula for dialysis for four weeks without any maturation-enhancing procedures. Secondary outcomes include assisted clinical maturation, ultrasound-based anatomical maturation, fistula procedures, fistula abandonment, and central venous catheter use. Measurements Pre-operative ultrasound arterial and venous mapping, flow-mediated and nitroglycerin-mediated brachial artery dilation, arterial pulse wave velocity, and venous distensibility; intra-operative vein tissue collection for histopathological and molecular analyses; post-operative ultrasounds at 1 day, 2 weeks, 6 weeks, and prior to fistula intervention and initial cannulation. Results Assuming complete data, no covariate adjustment, and unassisted clinical maturation of 50%, there will be 80% power to detect ORs of 1.83 and 1.61 for dichotomous predictor variables with exposure prevalences of 20% and 50%, respectively. Limitations Exclusion of two-stage transposition fistulas limits generalizability. The requirement for study visits may result in a cohort that is healthier than the overall population of patients undergoing fistula creation. Conclusions The HFM Study will be of sufficient size and scope to 1

  13. Teaching Ethics for Design for Sustainable Behaviour: A Pilot Study

    ERIC Educational Resources Information Center

    Lilley, Debra; Lofthouse, Vicky

    2010-01-01

    Design for sustainable behaviour is an emerging activity under the banner of sustainable design which aims to reduce the environmental and social impacts of products by moderating users' interaction with them. The intended outcome of design for sustainable behaviour is to reduce negative environmental and societal impacts. However, designers'…

  14. Self-Authored Graphic Design: A Strategy for Integrative Studies

    ERIC Educational Resources Information Center

    McCarthy, Steven; De Almeida, Cristina Melibeu

    2002-01-01

    The purpose of this essay is to introduce the concepts of self-authorship in graphic design education as part of an integrative pedagogy. The enhanced potential of harnessing graphic design's dual modalities--the integrative processes inherent in design thinking and doing, and the ability of graphic design to engage other disciplines by giving…

  15. Patterns of change in design metaphor: A case study

    SciTech Connect

    Stubblefield, W.A.

    1998-04-01

    Design metaphors play an important role in the development of many software projects. However, the influence of metaphors on project functionality, design methodology and the interactions among members of the development team is not well understood. This paper seeks insights into these issues by examining the experiences of a design team in building a system under the influence of a particularly strong design metaphor.

  16. Studying Classroom Interaction during a Design-without-Make Assignment

    ERIC Educational Resources Information Center

    Trebell, Donna

    2009-01-01

    This paper explores ways in which data collected during designerly activity in a Secondary Design and Technology Classroom in the UK, can be analysed with a view to ascertaining the features of the classroom interactions which facilitate the development of designerly activity in "fledgling designers" (Trebell, 2007). The paper builds…

  17. Studies relevant to the design of reliable automotive electronics

    NASA Astrophysics Data System (ADS)

    Zeng, Hua

    This dissertation describes three independent studies related to the design of reliable automotive electronics. The topics covered are: the estimation of the radiated emissions from power bus structures, EM propagation of tire pressure monitoring systems (TPMS), and examinations of corrosion-induced faults in a connector. The first chapter describes a method for estimating the maximum possible radiated emissions from a printed circuit board power bus. An analysis based on a lossy cavity model is performed to determine the maximum possible radiated field corresponding to a given power bus noise voltage. A closed-form expression relating the maximum power bus noise voltage to the radiation peaks is then derived. This expression is solved in reverse to determine the minimum power bus voltage necessary to generate a radiated field and can be applied to measured values of power bus noise voltage to determine whether radiation directly from the power bus is potentially the emissions source. The second chapter identifies transmission parameters from a rotating tire and the vehicle body's effect on tire sensor transmission and propagation; relates these effects to receiver antenna packaging requirements; and then, based on these results, proposes the antenna design of employing car body as a part. In the new proposed TPMS design, a 20mm x 5mm loop antenna with a 40mm x 10mm slot beneath it is added to capture the surface currents of the car body and block the current path to increase the current density around the loop antenna. The simulation results show that this design exhibits a propagation factor 150 times larger than the traditional design. The third chapter investigates the effects of different contaminants (salt, oil, grease) on the shunt resistance between pins of a cable connector. The test results show that salt-induced corrosion and moisture may cause intermittent shunting resistances capable of affecting the normal operation of automotive systems. One

  18. Experimental design considerations in microbiota/inflammation studies

    PubMed Central

    Moore, Robert J; Stanley, Dragana

    2016-01-01

    There is now convincing evidence that many inflammatory diseases are precipitated, or at least exacerbated, by unfavourable interactions of the host with the resident microbiota. The role of gut microbiota in the genesis and progression of diseases such as inflammatory bowel disease, obesity, metabolic syndrome and diabetes have been studied both in human and in animal, mainly rodent, models of disease. The intrinsic variation in microbiota composition, both within one host over time and within a group of similarly treated hosts, presents particular challenges in experimental design. This review highlights factors that need to be taken into consideration when designing animal trials to investigate the gastrointestinal tract microbiota in the context of inflammation studies. These include the origin and history of the animals, the husbandry of the animals before and during experiments, details of sampling, sample processing, sequence data acquisition and bioinformatic analysis. Because of the intrinsic variability in microbiota composition, it is likely that the number of animals required to allow meaningful statistical comparisons across groups will be higher than researchers have generally used for purely immune-based analyses. PMID:27525065

  19. Structural design feasibility study of Space Station long spacer truss

    NASA Technical Reports Server (NTRS)

    Armand, Sasan C.; Funk, Gregory P.; Dohogne, Caroline A.

    1994-01-01

    The structural design and configuration feasibility of the long spacer truss assembly that will be used as part of the Space Station Freedom is the focus of this study. The structural analysis discussed herein is derived from the transient loading events presented in the Space Transportation System Interface Control Document (STS ICD). The transient loading events are liftoff, landing, and emergency landing loads. Quasi-static loading events were neglected in this study since the magnitude of the quasi-static acceleration factors is lower than that of the transient acceleration factors. Structural analysis of the proposed configuration of the long spacer truss with four longerons indicated that negative safety margins are possible. As a result, configuration changes were proposed. The primary configuration change suggested was to increase the number of truss longerons to six. The six-longeron truss appears to be a more promising structure than the four-longeron truss because it offers a positive margin of safety and more volume in its second bay (BAY2). This additional volume can be used for resupply of some of the orbital replacement units (such as a battery box). Note that the design effort on the long spacer truss has not fully begun and that calculations and reports of the negative safety margins are, to date, based on concept only.

  20. The Generation R Study: design and cohort update 2017.

    PubMed

    Kooijman, Marjolein N; Kruithof, Claudia J; van Duijn, Cornelia M; Duijts, Liesbeth; Franco, Oscar H; van IJzendoorn, Marinus H; de Jongste, Johan C; Klaver, Caroline C W; van der Lugt, Aad; Mackenbach, Johan P; Moll, Henriëtte A; Peeters, Robin P; Raat, Hein; Rings, Edmond H H M; Rivadeneira, Fernando; van der Schroeff, Marc P; Steegers, Eric A P; Tiemeier, Henning; Uitterlinden, André G; Verhulst, Frank C; Wolvius, Eppo; Felix, Janine F; Jaddoe, Vincent W V

    2016-12-01

    The Generation R Study is a population-based prospective cohort study from fetal life until adulthood. The study is designed to identify early environmental and genetic causes and causal pathways leading to normal and abnormal growth, development and health from fetal life, childhood and young adulthood. This multidisciplinary study focuses on several health outcomes including behaviour and cognition, body composition, eye development, growth, hearing, heart and vascular development, infectious disease and immunity, oral health and facial growth, respiratory health, allergy and skin disorders of children and their parents. Main exposures of interest include environmental, endocrine, genomic (genetic, epigenetic, microbiome), lifestyle related, nutritional and socio-demographic determinants. In total, 9778 mothers with a delivery date from April 2002 until January 2006 were enrolled in the study. Response at baseline was 61%, and general follow-up rates until the age of 10 years were around 80%. Data collection in children and their parents includes questionnaires, interviews, detailed physical and ultrasound examinations, behavioural observations, lung function, Magnetic Resonance Imaging and biological sampling. Genome and epigenome wide association screens are available. Eventually, results from the Generation R Study contribute to the development of strategies for optimizing health and healthcare for pregnant women and children.

  1. The Generation R Study: design and cohort update 2012.

    PubMed

    Jaddoe, Vincent W V; van Duijn, Cornelia M; Franco, Oscar H; van der Heijden, Albert J; van Iizendoorn, Marinus H; de Jongste, Johan C; van der Lugt, Aad; Mackenbach, Johan P; Moll, Henriëtte A; Raat, Hein; Rivadeneira, Fernando; Steegers, Eric A P; Tiemeier, Henning; Uitterlinden, Andre G; Verhulst, Frank C; Hofman, Albert

    2012-09-01

    The Generation R Study is a population-based prospective cohort study from fetal life until adulthood. The study is designed to identify early environmental and genetic causes and causal pathways leading to normal and abnormal growth, development and health during fetal life, childhood and adulthood. The study focuses on six areas of research: (1) maternal health; (2) growth and physical development; (3) behavioural and cognitive development; (4) respiratory health and allergies; (5) diseases in childhood; and (6) health and healthcare for children and their parents. Main exposures of interest include environmental, endocrine, genetic and epigenetic, lifestyle related, nutritional and socio-demographic determinants. In total, n = 9,778 mothers with a delivery date from April 2002 until January 2006 were enrolled in the study. Response at baseline was 61 %, and general follow-up rates until the age of 6 years exceed 80 %. Data collection in mothers, fathers and children include questionnaires, detailed physical and ultrasound examinations, behavioural observations, and biological samples. A genome and epigenome wide association screen is available in the participating children. From the age of 5 years, regular detailed hands-on assessments are performed in a dedicated research center including advanced imaging facilities such as Magnetic Resonance Imaging. Eventually, results forthcoming from the Generation R Study contribute to the development of strategies for optimizing health and healthcare for pregnant women and children.

  2. Environmental exposure and mitochondrial epigenetics: study design and analytical challenges

    PubMed Central

    Byun, Hyang-Min; Baccarelli, Andrea A.

    2015-01-01

    The environment can influence human health and disease in many harmful ways. Many epidemiological studies have been conducted with the aim of elucidating the association between environmental exposure and human disease at the molecular and pathological levels, and such associations can often be through induced epigenetic changes. One such mechanism for this is through environmental factors increasing oxidative stress in the cell, and this stress can subsequently lead to alterations in DNA molecules. The two cellular organelles that contain DNA are the nucleus and mitochondria, and the latter are particularly sensitive to oxidative stress, with mitochondrial functions often disrupted by increased stress. There has been a substantial increase over the past decade in the number of epigenetic studies investigating the impact of environmental exposures upon genomic DNA, but to date there has been insufficient attention paid to the impact upon mitochondrial epigenetics in studying human disease with exposure to environment. Here, in this review, we will discuss mitochondrial epigenetics with regards to epidemiological studies, with particular consideration given to study design and analytical challenges. Furthermore, we suggest future directions and perspectives in the field of mitochondrial epigenetic epidemiological studies. PMID:24402053

  3. 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.

  4. Photovoltaic module electrical termination design requirement study. Final report

    SciTech Connect

    Mosna, F.J. Jr.; Donlinger, J.

    1980-07-01

    Motorola Inc., in conjunction with ITT Cannon, has conducted a study to develop information to facilitate the selection of existing, commercial, electrical termination hardware for photovoltaic modules and arrays. Details of the study are presented in this volume. Module and array design parameters were investigated and recommendations were developed for use in surveying, evaluating, and comparing electrical termination hardware. Electrical termination selection criteria factors were developed and applied to nine generic termination types in each of the four application sectors. Remote, residential, intermediate and industrial. Existing terminations best suited for photovoltaic modules and arrays were identified. Cost information was developed to identify cost drivers and/or requirements which might lead to cost reductions. The general conclusion is that there is no single generic termination that is best suited for photovoltaic application, but that the appropriate termination is strongly dependent upon the module construction and its support structure as well as the specific application sector.

  5. Effect and interaction study of acetamiprid photodegradation using experimental design.

    PubMed

    Tassalit, Djilali; Chekir, Nadia; Benhabiles, Ouassila; Mouzaoui, Oussama; Mahidine, Sarah; Merzouk, Nachida Kasbadji; Bentahar, Fatiha; Khalil, Abbas

    2016-10-01

    The methodology of experimental research was carried out using the MODDE 6.0 software to study the acetamiprid photodegradation depending on the operating parameters, such as the initial concentration of acetamiprid, concentration and type of the used catalyst and the initial pH of the medium. The results showed the importance of the pollutant concentration effect on the acetamiprid degradation rate. On the other hand, the amount and type of the used catalyst have a considerable influence on the elimination kinetics of this pollutant. The degradation of acetamiprid as an environmental pesticide pollutant via UV irradiation in the presence of titanium dioxide was assessed and optimized using response surface methodology with a D-optimal design. The acetamiprid degradation ratio was found to be sensitive to the different studied factors. The maximum value of discoloration under the optimum operating conditions was determined to be 99% after 300 min of UV irradiation.

  6. Designing Games, Designing Roles: A Study of Youth Agency in an Urban Informal Education Program

    ERIC Educational Resources Information Center

    Sheridan, Kimberly M.; Clark, Kevin; Williams, Asia

    2013-01-01

    Collaboration (GDMC), an informal education program in 3D computer modeling and 2D interactive game design serving primarily African American youth aged 7 to 19 years in the Washington, D.C. metro area, transformed from a program designed and taught by adults to one designed and taught by youth. In Year 1, 8% of youth participants held a…

  7. Optimal design strategies for sibling studies with binary exposures.

    PubMed

    Li, Zhigang; McKeague, Ian W; Lumey, Lambert H

    2014-01-01

    Sibling studies have become increasingly popular because they provide better control over confounding by unmeasured family-level risk factors than can be obtained in standard cohort studies. However, little attention has been devoted to the development of efficient design strategies for sibling studies in terms of optimizing power. We here address this issue in commonly encountered types of sibling studies, allowing for continuous and binary outcomes and varying numbers of exposed and unexposed siblings. For continuous outcomes, we show that in families with sibling pairs, optimal study power is obtained by recruiting discordant (exposed-control) pairs of siblings. More generally, balancing the exposure status within each family as evenly as possible is shown to be optimal. For binary outcomes, we elucidate how the optimal strategy depends on the variation of the binary response; as the within-family correlation increases, the optimal strategy tends toward only recruiting discordant sibling pairs (as in the case of continuous outcomes). R code for obtaining the optimal strategies is included.

  8. Study, simulation and design of a 3D clinostat

    NASA Astrophysics Data System (ADS)

    Pavone, Valentina; Guarnieri, Vincenzo; Lobascio, Cesare; Soma, Aurelio; Bosso, Nicola; Lamantea, Matteo Maria

    High cost and limited number of physically executable experiments in space have introduced the need for ground simulation systems that enable preparing experiments to be carried out on board, identifying phenomena associated with the altered gravity conditions, and taking advantage of these conditions, as in Biotechnology. Among systems developed to simulate microgravity, especially for life sciences experiments, different types of clinostats were realized. This work deals with mechanical design of a three-dimensional clinostat and simulation of the dynamic behavior of the system by varying the operating parameters. The design and simulation phase was preceded by a careful analysis of the state of art and by the review of the most recent results, in particular from the major investigators of Life Sciences in Space. The mechanical design is quite innovative by adoption of a structure entirely in aluminum, which allows robustness while reducing the overall weight. The transmission system of motion has been optimized by means of brushless DC micro motors, light and compact, which helped to reduce weight, dimensions, power consumption and increase the reliability and durability of the system. The study of the dynamic behavior using SIMPACK, a multibody simulation software, led to results in line with those found in the most important and recent scientific publications. This model was also appropriately configured to represent any desired operating condition, and for eventual system scalability. It would be interesting to generate simulated hypogravity - e.g.: 0.38-g (Mars) or 0.17-g (Moon). This would allow to investigate how terrestrial life forms can grow in other planetary habitats, or to determine the gravity threshold response of different organisms. At the moment, such a system can only be achieved by centrifuges in real microgravity. We are confident that simulation and associated tests with our 3D clinostat can help adjusting the parameters allowing variable g

  9. Ultra-Supercritical Pressure CFB Boiler Conceptual Design Study

    SciTech Connect

    Zhen Fan; Steve Goidich; Archie Robertson; Song Wu

    2006-06-30

    Electric utility interest in supercritical pressure steam cycles has revived in the United States after waning in the 1980s. Since supercritical cycles yield higher plant efficiencies than subcritical plants along with a proportional reduction in traditional stack gas pollutants and CO{sub 2} release rates, the interest is to pursue even more advanced steam conditions. The advantages of supercritical (SC) and ultra supercritical (USC) pressure steam conditions have been demonstrated in the high gas temperature, high heat flux environment of large pulverized coal-fired (PC) boilers. Interest in circulating fluidized bed (CFB) combustion, as an alternative to PC combustion, has been steadily increasing. Although CFB boilers as large as 300 MWe are now in operation, they are drum type, subcritical pressure units. With their sizes being much smaller than and their combustion temperatures much lower than those of PC boilers (300 MWe versus 1,000 MWe and 1600 F versus 3500 F), a conceptual design study was conducted herein to investigate the technical feasibility and economics of USC CFB boilers. The conceptual study was conducted at 400 MWe and 800 MWe nominal plant sizes with high sulfur Illinois No. 6 coal used as the fuel. The USC CFB plants had higher heating value efficiencies of 40.6 and 41.3 percent respectively and their CFB boilers, which reflect conventional design practices, can be built without the need for an R&D effort. Assuming construction at a generic Ohio River Valley site with union labor, total plant costs in January 2006 dollars were estimated to be $1,551/kW and $1,244/kW with costs of electricity of $52.21/MWhr and $44.08/MWhr, respectively. Based on the above, this study has shown that large USC CFB boilers are feasible and that they can operate with performance and costs that are competitive with comparable USC PC boilers.

  10. Results of Parametric Design Studies of MOX Lead Test Assembly

    SciTech Connect

    Pavlovitchev, A.M.; Bychkov, S.A.; Lazarenko, A.A.; Sidorenko, V.D.; Styrin, Y.A.

    1998-12-01

    The parametric studies of MOX LTA design have been executed to choose plutonium content in assembly zones for two options of MOX LTA: 3-zones and Island. For 3-zones (100% Plutonium) MOX LTA the fissile plutonium content composition of 4.2%/3,0%/2% has been chosen. MOX LTA of the chosen compositions has been studied by using multi-assembly configuration that allows investigating of influence of MOX LTA environment: uranium assemblies of different irradiation. Plutonium Island with 54 plutonium pins in the center of MOX LTA has been considered in two modifications: uniform island; and graded island with lower plutonium content in one peripheral row of pins. It is shown that plutonium content in the uniform island cannot exceed 2.7% because of adopted power peaking limitations and therefore this design seems unreasonable for practical use. For graded island the plutonium content composition 3.8%/2.8% with uranium environment of 3.7% U-235 has been chosen. Evolution of assembly power and burnup distributions, inter-pin power and isotopic distributions while fuel irradiating have been analyzed. In addition to the base uranium environment of 3.7%, a set of calculations has been executed for 4.4%. Most of the studies have been executed by the code TVS-M that is at the final stage of licensing and it is to be used in the nearest future as a base instrument for VVER core calculations while using both uranium and MOX fuel. So the obtained results must be considered as preliminary ones and they demand additional analysis and investigations.

  11. Hybrid vehicle system studies and optimized hydrogen engine design

    NASA Astrophysics Data System (ADS)

    Smith, J. R.; Aceves, S.

    1995-04-01

    We have done system studies of series hydrogen hybrid automobiles that approach the PNGV design goal of 34 km/liter (80 mpg), for 384 km (240 mi) and 608 km (380 mi) ranges. Our results indicate that such a vehicle appears feasible using an optimized hydrogen engine. We have evaluated the impact of various on-board storage options on fuel economy. Experiments in an available engine at the Sandia CRF demonstrated NO(x) emissions of 10 to 20 ppM at an equivalence ratio of 0.4, rising to about 500 ppm at 0.5 equivalence ratio using neat hydrogen. Hybrid simulation studies indicate that exhaust NO(x) concentrations must be less than 180 ppM to meet the 0.2 g/mile ULEV or Federal Tier II emissions regulations. LLNL has designed and fabricated a first generation optimized hydrogen engine head for use on an existing Onan engine. This head features 15:1 compression ratio, dual ignition, water cooling, two valves and open quiescent combustion chamber to minimize heat transfer losses. Initial testing shows promise of achieving an indicated efficiency of nearly 50% and emissions of less than 100 ppM NO(x). Hydrocarbons and CO are to be measured, but are expected to be very low since their only source is engine lubricating oil. A successful friction reduction program on the Onan engine should result in a brake thermal efficiency of about 42% compared to today's gasoline engines of 32%. Based on system studies requirements, the next generation engine will be about 2 liter displacement and is projected to achieve 46% brake thermal efficiency with outputs of 15 kW for cruise and 40 kW for hill climb.

  12. 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.…

  13. CAES/UPH hybrid plant design study. Phase I

    SciTech Connect

    1980-12-01

    In spite of the technical and economic feasibility of Compressed Air Energy Storage (CAES) and Underground Pumped Storage (UPH), there appears to be several barriers to their implementation and commercialization. These potential barriers include: large installed capacity is required to bring UPH plant economics into a favorable position and CAES requires consumption of petroleum distillate or natural gas. This study was undertaken to investigate means to remove these barriers by: identifying and evaluating the potential benefits that might be achieved by combining UPH, CAES and other related processes, and developing potential combination designs incorporating these benefits to determine their technical and economical feasibility. The development of specific UPH, CAES, and hybrid UPH/CAES concepts are discussed and evaluated. The results of the work performed to date show that development of conventional CAES and UPH design configurations is proceeding rapidly. The direction of this development will probably eventually result in a range of large scale energy storage plant types that will be attractive to electric utilities. However, the rate of development may be unacceptably slow for some of these variants to assist in effective reduction of distillate oil consumption for peaking power. It is recommended that an acceleration of the development rate of coal-fired CAES and adiabatic CAES concepts be organized. These two concepts, if adopted by electric utilities, could make a substantial contribution to the nation's effort to reduce oil imports. (LCL)

  14. Design study of long-life PWR using thorium cycle

    SciTech Connect

    Subkhi, Moh. Nurul; Su'ud, Zaki; Waris, Abdul

    2012-06-06

    Design study of long-life Pressurized Water Reactor (PWR) using thorium cycle has been performed. Thorium cycle in general has higher conversion ratio in the thermal spectrum domain than uranium cycle. Cell calculation, Burn-up and multigroup diffusion calculation was performed by PIJ-CITATION-SRAC code using libraries based on JENDL 3.2. The neutronic analysis result of infinite cell calculation shows that {sup 231}Pa better than {sup 237}Np as burnable poisons in thorium fuel system. Thorium oxide system with 8%{sup 233}U enrichment and 7.6{approx} 8%{sup 231}Pa is the most suitable fuel for small-long life PWR core because it gives reactivity swing less than 1%{Delta}k/k and longer burn up period (more than 20 year). By using this result, small long-life PWR core can be designed for long time operation with reduced excess reactivity as low as 0.53%{Delta}k/k and reduced power peaking during its operation.

  15. Preliminary design studies on a nuclear seawater desalination system

    SciTech Connect

    Wibisono, A. F.; Jung, Y. H.; Choi, J.; Kim, H. S.; Lee, J. I.; Jeong, Y. H.; No, H. C.

    2012-07-01

    Seawater desalination is one of the most promising technologies to provide fresh water especially in the arid region. The most used technology in seawater desalination are thermal desalination (MSF and MED) and membrane desalination (RO). Some developments have been done in the area of coupling the desalination plant with a nuclear reactor to reduce the cost of energy required in thermal desalination. The coupling a nuclear reactor to a desalination plant can be done either by using the co-generation or by using dedicated heat from a nuclear system. The comparison of the co-generation nuclear reactor with desalination plant, dedicated nuclear heat system, and fossil fueled system will be discussed in this paper using economical assessment with IAEA DEEP software. A newly designed nuclear system dedicated for the seawater desalination will also be suggested by KAIST (Korea Advanced Inst. of Science and Technology) research team and described in detail within this paper. The suggested reactor system is using gas cooled type reactor and in this preliminary study the scope of design will be limited to comparison of two cases in different operating temperature ranges. (authors)

  16. Study of the neutron beam line shield design for JSNS.

    PubMed

    Kawai, M; Saito, K; Sanami, T; Nakao, N; Maekawa, F

    2005-01-01

    The JSNS, a spallation neutron source of J-PARC (JAERI-KEK Joint Project of the High Intensity Proton Accelerator) has 23 neutron beam lines. In the present study, a database was formulated for an optimum shielding design using the MCNP-X code. The calculations involved two steps. In the first step, the neutron distributions were created in the typical neutron beam line with a model that included the spallation neutron source target. The neutron currents evaluated flowed from the duct into the duct wall which was the boundary source for the bulk shield surrounding the beam line. In the second step, bulk-shield calculations were performed for the various shielding materials (iron, concrete, heavy concrete and so on) used and their composites up to thicknesses of 3 m. The results were compared with each other. Composite material shields of iron and such hydrogeneous materials as polyethylene or concrete were more effective. A typical design was prepared for a beam line within 25 m distance from a moderator, as a sample.

  17. Tradeoff studies in multiobjective insensitive design of airplane control systems

    NASA Technical Reports Server (NTRS)

    Schy, A. A.; Giesy, D. P.

    1983-01-01

    A computer aided design method for multiobjective parameter-insensitive design of airplane control systems is described. Methods are presented for trading off nominal values of design objectives against sensitivities of the design objectives to parameter uncertainties, together with guidelines for designer utilization of the methods. The methods are illustrated by application to the design of a lateral stability augmentation system for two supersonic flight conditions of the Shuttle Orbiter. Objective functions are conventional handling quality measures and peak magnitudes of control deflections and rates. The uncertain parameters are assumed Gaussian, and numerical approximations of the stochastic behavior of the objectives are described. Results of applying the tradeoff methods to this example show that stochastic-insensitive designs are distinctly different from deterministic multiobjective designs. The main penalty for achieving significant decrease in sensitivity is decreased speed of response for the nominal system.

  18. Earth Observatory Satellite system definition study. Report no. 3: Design/cost tradeoff studies

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The key issues in the Earth Observatory Satellite (EOS) program which are subject to configuration study and tradeoff are identified. The issue of a combined operational and research and development program is considered. It is stated that cost and spacecraft weight are the key design variables and design options are proposed in terms of these parameters. A cost analysis of the EOS program is provided. Diagrams of the satellite configuration and subsystem components are included.

  19. Inertial Fusion Energy reactor design studies: Prometheus-L, Prometheus-H. Volume 1, Final report

    SciTech Connect

    Waganer, L.M.; Driemeyer, D.E.; Lee, V.D.

    1992-03-01

    This report contains a review of design studies for inertial confinement reactors. The first of three volumes briefly discusses the following: Introduction; Key objectives, requirements, and assumptions; Systems modeling and trade studies; Prometheus-L reactor plant design overview; Prometheus-H reactor plant design overview; Key technical issues and R&D requirements; Comparison of IFE designs; and study conclusions.

  20. Conceptual design study of improved automotives gas turbine powertrain

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Twenty-two candidate engine concepts and nineteen transmission concepts. Screening of these concepts, predominantly for fuel economy, cost and technical risk, resulted in a recommended powertrain consisting of a single-shaft engine, with a ceramic radial turbine rotor, connected through a differential split-power transmission utilizing a variable stator torque converter and a four speed automatic gearbox. Vehicle fuel economy and performance projections, preliminary design analyses and installation studies in a were completed. A cost comparison with the conventional spark ignited gasoline engine showed that the turbine engine would be more expensive initially, however, lifetime cost of ownership is in favor of the gas turbine. A powertrain research and development plan was constructed to gain information on timing and costs to achieve the required level of technology and demonstrate the engine in a vehicle by the year 1983.

  1. Preliminary Design Study for a National Digital Seismograph Network

    USGS Publications Warehouse

    Peterson, Jon; Hutt, Charles R.

    1981-01-01

    Introduction Recently, the National Research Council published a report by the Panel on National, Regional, and Local Seismograph Networks of the Committee on Seismology in which the principal recommendation was for the establishment of a national digital seismograph network (NDSN). The Panel Report (Bolt, 1980) addresses both the need and the scientific requirements for the new national network. The purpose of this study has been to translate the scientific requirements into an instrumentation concept for the NSDS. There are literally hundreds, perhaps thousands, of seismographs in operation within the United States. Each serves an important purpose, but most have limited objectives in time, in region, or in the types of data that are being recorded. The concept of a national network, funded and operated by the Federal Government, is based on broader objectives that include continuity of time, uniform coverage, standardization of data format and instruments, and widespread use of the data for a variety of research purposes. A national digital seismograph network will be an important data resource for many years to come; hence, its design is likely to be of interest to most seismologists. Seismologists have traditionally been involved in the development and field operation of seismic systems and thus have been familiar with both the potential value and the limitations of the data. However, in recent years of increasing technological sophistication, the development of data sstems has fallen more to system engineers, and this trend is likely to continue. One danger in this is that the engineers may misinterpret scientific objectives or subordinate them to purely technological considerations. Another risk is that the data users may misuse or misinterpret the data because they are not aware of the limitations of the data system. Perhaps the most important purpose of a design study such as this is to stimulate a dialogue between system engineers and potential data users

  2. CFRP panel concept design study for the CCAT

    NASA Astrophysics Data System (ADS)

    Martin, Robert N.; Romeo, Robert C.; Kingsley, Jeffrey S.

    2006-06-01

    Under contract from the Cornell-Caltech Atacama Telescope Project (CCAT), Composite Mirror Applications, Inc. (CMA) has undertaken a feasibility design study for the use of Carbon Fiber Reinforced Plastic (CFRP) panels in forming the primary mirror surface. We review some of the past projects using CFRP panel technology for millimeter and submillimeter wavelength radio astronomy telescopes. Pros and cons of the technology are discussed. A particular panel configuration was proposed and computer modeled with finite element analysis (FEA). The technology of replicated CFRP panels for short wavelength radio astronomical telescopes is mature and cost effective. For shorter wavelengths into the IR and visible, it is becoming a very attractive alternative to traditional, heavy glass or metal technologies.

  3. Design study for LANDSAT-D attitude control system

    NASA Technical Reports Server (NTRS)

    Iwens, R. P.; Bernier, G. E.; Hofstadter, R. F.; Mayo, R. A.; Nakano, H.

    1977-01-01

    The gimballed Ku-band antenna system for communication with TDRS was studied. By means of an error analysis it was demonstrated that the antenna cannot be open loop pointed to TDRS by an onboard programmer, but that an autotrack system was required. After some tradeoffs, a two-axis, azimuth-elevation type gimbal configuration was recommended for the antenna. It is shown that gimbal lock only occurs when LANDSAT-D is over water where a temporary loss of the communication link to TDRS is of no consequence. A preliminary gimbal control system design is also presented. A digital computer program was written that computes antenna gimbal angle profiles, assesses percent antenna beam interference with the solar array, and determines whether the spacecraft is over land or water, a lighted earth or a dark earth, and whether the spacecraft is in eclipse.

  4. Southeastern Virginia Urban Plume Study design considerations and measurement results

    NASA Technical Reports Server (NTRS)

    Mcdougal, D. S.; Gregory, G. L.

    1980-01-01

    The Southeastern Virginia Urban Plume Study is intended to provide a testing ground for NASA remote sensors designed for urban and regional scale monitoring of air quality phenomena. The air quality experiments it has conducted have incorporated surface, airborne, sonde and balloon platforms which measured air quality and meteorology parameters, with emphasis on photochemically produced O3 and its primary precursors upwind, above, and downwind of the Hampton Roads area urban complex. The results from three years of experiments have shown that such different meteorological conditions as blue/broken skies, high/moderate temperatures and low/high winds have a direct impact on the degree of downwind aging of the summer urban O3 airmass. In 1979, the urban plume was traced at aging times of 0.5, 1.5, and 5 hr.

  5. Technological issues and experimental design of gene association studies.

    PubMed

    Distefano, Johanna K; Taverna, Darin M

    2011-01-01

    Genome-wide association studies (GWAS), in which thousands of single-nucleotide polymorphisms (SNPs) spanning the genome are genotyped in individuals who are phenotypically well characterized, -currently represent the most popular strategy for identifying gene regions associated with common -diseases and related quantitative traits. Improvements in technology and throughput capability, development of powerful statistical tools, and more widespread acceptance of pooling-based genotyping approaches have led to greater utilization of GWAS in human genetics research. However, important considerations for optimal experimental design, including selection of the most appropriate genotyping platform, can enhance the utility of the approach even further. This chapter reviews experimental and technological issues that may affect the success of GWAS findings and proposes strategies for developing the most comprehensive, logical, and cost-effective approaches for genotyping given the population of interest.

  6. Design study of a longer wavelength FEL for FELIX

    SciTech Connect

    Lin, L.; Oepts, D.; Meer, A.F.G. van der

    1995-12-31

    We present a design study of FEL3, which will extend the FELIX spectral range towards a few hundred microns. A rectangular waveguide will be used to reduce diffraction losses. Calculations show that with a waveguide gap of 1 cm, only one sinusoidal mode along the guided direction can exist within the FEL gain bandwidth, thus excluding group velocity dispersion and lengthening of short radiation pulses. To incorporate FEL3 in the existing FELIX facility, two options are being considered: to combine FEL3 with FEL1 by insertion of a waveguide into FEL1, and to build a dedicated third beam line for FEL3 after the two linacs. Expected FEL performance: gain, spectrum, power, pulse shape, etc., will be presented based on numerical simulations.

  7. Arab Teens Lifestyle Study (ATLS): objectives, design, methodology and implications

    PubMed Central

    Al-Hazzaa, Hazzaa M; Musaiger, Abdulrahman O

    2011-01-01

    Background There is a lack of comparable data on physical activity, sedentary behavior, and dietary habits among Arab adolescents, which limits our understanding and interpretation of the relationship between obesity and lifestyle parameters. Therefore, we initiated the Arab Teens Lifestyle Study (ATLS). The ATLS is a multicenter collaborative project for assessing lifestyle habits of Arab adolescents. The objectives of the ATLS project were to investigate the prevalence rates for overweight and obesity, physical activity, sedentary activity and dietary habits among Arab adolescents, and to examine the interrelationships between these lifestyle variables. This paper reports on the objectives, design, methodology, and implications of the ATLS. Design/Methods The ATLS is a school-based cross-sectional study involving 9182 randomly selected secondary-school students (14–19 years) from major Arab cities, using a multistage stratified sampling technique. The participating Arab cities included Riyadh, Jeddah, and Al-Khobar (Saudi Arabia), Bahrain, Dubai (United Arab Emirates), Kuwait, Amman (Jordan), Mosel (Iraq), Muscat (Oman), Tunisia (Tunisia) and Kenitra (Morocco). Measured variables included anthropometric measurements, physical activity, sedentary behavior, sleep duration, and dietary habits. Discussion The ATLS project will provide a unique opportunity to collect and analyze important lifestyle information from Arab adolescents using standardized procedures. This is the first time a collaborative Arab project will simultaneously assess broad lifestyle variables in a large sample of adolescents from numerous urbanized Arab regions. This joint research project will supply us with comprehensive and recent data on physical activity/inactivity and eating habits of Arab adolescents relative to obesity. Such invaluable lifestyle-related data are crucial for developing public health policies and regional strategies for health promotion and disease prevention. PMID

  8. Design Study of an Incinerator Ash Conveyor Counting System - 13323

    SciTech Connect

    Jaederstroem, Henrik; Bronson, Frazier

    2013-07-01

    A design study has been performed for a system that should measure the Cs-137 activity in ash from an incinerator. Radioactive ash, expected to consist of both Cs-134 and Cs-137, will be transported on a conveyor belt at 0.1 m/s. The objective of the counting system is to determine the Cs-137 activity and direct the ash to the correct stream after a diverter. The decision levels are ranging from 8000 to 400000 Bq/kg and the decision error should be as low as possible. The decision error depends on the total measurement uncertainty which depends on the counting statistics and the uncertainty in the efficiency of the geometry. For the low activity decision it is necessary to know the efficiency to be able to determine if the signal from the Cs-137 is above the minimum detectable activity and that it generates enough counts to reach the desired precision. For the higher activity decision the uncertainty of the efficiency needs to be understood to minimize decision errors. The total efficiency of the detector is needed to be able to determine if the detector will be able operate at the count rate at the highest expected activity. The design study that is presented in this paper describes how the objectives of the monitoring systems were obtained, the choice of detector was made and how ISOCS (In Situ Object Counting System) mathematical modeling was used to calculate the efficiency. The ISOCS uncertainty estimator (IUE) was used to determine which parameters of the ash was important to know accurately in order to minimize the uncertainty of the efficiency. The examined parameters include the height of the ash on the conveyor belt, the matrix composition and density and relative efficiency of the detector. (authors)

  9. Design study of RL10 derivatives. Volume 2: Engine design characteristics. [application of rocket engine to space tug propulsion

    NASA Technical Reports Server (NTRS)

    Adams, A.

    1973-01-01

    The design characteristics of the RL-10 rocket engine are discussed. The results from critical elements evaluation, baseline engine design, parametric and special study tasks are presented. Critical element evaluation established the feasibility of various engine features such as tank head idle, pumped idle, autogenous tank pressurization, and two-phase pumping. Three baseline engines, derived from the RL-10 were conceptually designed. Parametric life and performance data were generated. Special studies were conducted to establish the impact on the engine design of environment, safety, interchangeability, and maintenance.

  10. [Historical cohort study in the German rubber industry: goals, study design and data collection].

    PubMed

    Birk, T; Weiland, S K; Schumann, J; Person, M; Mundt, K; Keil, U

    1995-01-01

    A historical cohort study is carried out to investigate occupational hazards in the German rubber industry since 1991. We present and discuss the study objectives and study design features such as cohort definition, assessment of occupational exposure and selection of the reference population. Cohort enumeration, assessment of vital status and cause of death ascertainment are described. With approximately 2,800 deaths throughout the observation period 1981 to 1991 it will be possible also to study the occupational etiology of rare diseases.

  11. Scaling studies and conceptual experiment designs for NGNP CFD assessment

    SciTech Connect

    D. M. McEligot; G. E. McCreery

    2004-11-01

    The objective of this report is to document scaling studies and conceptual designs for flow and heat transfer experiments intended to assess CFD codes and their turbulence models proposed for application to prismatic NGNP concepts. The general approach of the project is to develop new benchmark experiments for assessment in parallel with CFD and coupled CFD/systems code calculations for the same geometry. Two aspects of the complex flow in an NGNP are being addressed: (1) flow and thermal mixing in the lower plenum ("hot streaking" issue) and (2) turbulence and resulting temperature distributions in reactor cooling channels ("hot channel" issue). Current prismatic NGNP concepts are being examined to identify their proposed flow conditions and geometries over the range from normal operation to decay heat removal in a pressurized cooldown. Approximate analyses have been applied to determine key non-dimensional parameters and their magnitudes over this operating range. For normal operation, the flow in the coolant channels can be considered to be dominant turbulent forced convection with slight transverse property variation. In a pressurized cooldown (LOFA) simulation, the flow quickly becomes laminar with some possible buoyancy influences. The flow in the lower plenum can locally be considered to be a situation of multiple hot jets into a confined crossflow -- with obstructions. Flow is expected to be turbulent with momentumdominated turbulent jets entering; buoyancy influences are estimated to be negligible in normal full power operation. Experiments are needed for the combined features of the lower plenum flows. Missing from the typical jet experiments available are interactions with nearby circular posts and with vertical posts in the vicinity of vertical walls - with near stagnant surroundings at one extreme and significant crossflow at the other. Two types of heat transfer experiments are being considered. One addresses the "hot channel" problem, if necessary

  12. Astronomy sortie missions definition study. Volume 3, book 1: Design analysis and trade studies

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A study to define the astronomy sortie missions was conducted. The design analyses and tradeoff studies conducted for candidate concepts are presented. The subjects discussed are: (1) system and subsystem requirements, (2) space shuttle interfaces, (3) infrared telescope development, and (4) experiments to be conducted during the mission.

  13. The Energy Balance Study: The Design and Baseline Results for a Longitudinal Study of Energy Balance

    ERIC Educational Resources Information Center

    Hand, Gregory A.; Shook, Robin P.; Paluch, Amanda E.; Baruth, Meghan; Crowley, E. Patrick; Jaggers, Jason R.; Prasad, Vivek K.; Hurley, Thomas G.; Hebert, James R.; O'Connor, Daniel P.; Archer, Edward; Burgess, Stephanie; Blair, Steven N.

    2013-01-01

    Purpose: The Energy Balance Study (EBS) was a comprehensive study designed to determine over a period of 12 months the associations of caloric intake and energy expenditure on changes in body weight and composition in a population of healthy men and women. Method: EBS recruited men and women aged 21 to 35 years with a body mass index between 20…

  14. X-43D Conceptual Design and Feasibility Study

    NASA Technical Reports Server (NTRS)

    Johnson, Donald B.; Robinson, Jeffrey S.

    2005-01-01

    NASA s Next Generation Launch Technology (NGLT) Program, in conjunction with the office of the Director of Defense Research and Engineering (DDR&E), developed an integrated hypersonic technology demonstration roadmap. This roadmap is an integral part of the National Aerospace Initiative (NAI), a multi-year, multi-agency cooperative effort to invest in and develop, among other things, hypersonic technologies. This roadmap contains key ground and flight demonstrations required along the path to developing a reusable hypersonic space access system. One of the key flight demonstrations required for systems that will operate in the high Mach number regime is the X-43D. As currently conceived, the X-43D is a Mach 15 flight test vehicle that incorporates a hydrogen-fueled scramjet engine. The purpose of the X-43D is to gather high Mach number flight environment and engine operability information which is difficult, if not impossible, to gather on the ground. During 2003, the NGLT Future Hypersonic Flight Demonstration Office initiated a feasibility study on the X-43D. The objective of the study was to develop a baseline conceptual design, assess its performance, and identify the key technical issues. The study also produced a baseline program plan, schedule, and cost, along with a list of key programmatic risks.

  15. Recent design and cost studies for air blown gasification

    SciTech Connect

    Dawes, S.G.; Mordecai, M.; Welford, G.B.; Otter, N.R.

    1997-12-31

    The Air Blown Gasification Cycle (ABGC) (formerly known as the British Coal Topping Cycle) is a high efficiency low cost system for producing power with excellent environmental performance. High efficiency is achieved without the complexity associated with other advanced cycles and the technology can be introduced in a modular fashion. Being a simple air blown fluid bed gasifier and combustor combination it is capable of using a wide range of fuels and is particularly suited for dealing with high ash melting point fuels found in areas of the world short of natural gas. An extensive program of pilot plant testing of a variety of fuels is now being completed on the test facility at the Coal Technology Development Division (CTDD) of British Coal as part of a UK program to develop the Air Blown Gasification Cycle. This program is supplying data to produce a design specification for a Prototype Integrated Plant (PIP) of around 90 MWe, and is managed by a consortium, the Clean Coal Power Generation Group. The paper summarizes recent results and operating experience for the pilot plant including fuel behavior studies, research in hot gas cleaning (particulate and gaseous contaminants), and gas combustion experience. The various cost studies undertaken on the ABGC are outlined and compared, including recent studies by EPRI.

  16. Lunar Lander Structural Design Studies at NASA Langley

    NASA Technical Reports Server (NTRS)

    Wu, K. Chauncey; Antol, Jeffrey; Watson, Judith J.; Flick, John J.; Saucillo, Rudolph J.; Mazanek, Daniel D.; North, David D.

    2007-01-01

    The National Aeronautics and Space Administration is currently developing mission architectures, vehicle concepts and flight hardware to support the planned human return to the Moon. During Phase II of the 2006 Lunar Lander Preparatory Study, a team from the Langley Research Center was tasked with developing and refining two proposed Lander concepts. The Descent-Assisted, Split Habitat Lander concept uses a disposable braking stage to perform the lunar orbit insertion maneuver and most of the descent from lunar orbit to the surface. The second concept, the Cargo Star Horizontal Lander, carries ascent loads along its longitudinal axis, and is then rotated in flight so that its main engines (mounted perpendicular to the vehicle longitudinal axis) are correctly oriented for lunar orbit insertion and a horizontal landing. Both Landers have separate crew transport volumes and habitats for surface operations, and allow placement of large cargo elements very close to the lunar surface. As part of this study, lightweight, efficient structural configurations for these spacecraft were proposed and evaluated. Vehicle structural configurations were first developed, and preliminary structural sizing was then performed using finite element-based methods. Results of selected structural design and trade studies performed during this activity are presented and discussed.

  17. Design and methods of the national Vietnam veterans longitudinal study.

    PubMed

    Schlenger, William E; Corry, Nida H; Kulka, Richard A; Williams, Christianna S; Henn-Haase, Clare; Marmar, Charles R

    2015-09-01

    The National Vietnam Veterans Longitudinal Study (NVVLS) is the second assessment of a representative cohort of US veterans who served during the Vietnam War era, either in Vietnam or elsewhere. The cohort was initially surveyed in the National Vietnam Veterans Readjustment Study (NVVRS) from 1984 to 1988 to assess the prevalence, incidence, and effects of post-traumatic stress disorder (PTSD) and other post-war problems. The NVVLS sought to re-interview the cohort to assess the long-term course of PTSD. NVVLS data collection began July 3, 2012 and ended May 17, 2013, comprising three components: a mailed health questionnaire, a telephone health survey interview, and, for a probability sample of theater Veterans, a clinical diagnostic telephone interview administered by licensed psychologists. Excluding decedents, 78.8% completed the questionnaire and/or telephone survey, and 55.0% of selected living veterans participated in the clinical interview. This report provides a description of the NVVLS design and methods. Together, the NVVRS and NVVLS constitute a nationally representative longitudinal study of Vietnam veterans, and extend the NVVRS as a critical resource for scientific and policy analyses for Vietnam veterans, with policy relevance for Iraq and Afghanistan veterans.

  18. Optimized design and analysis of preclinical intervention studies in vivo

    PubMed Central

    Laajala, Teemu D.; Jumppanen, Mikael; Huhtaniemi, Riikka; Fey, Vidal; Kaur, Amanpreet; Knuuttila, Matias; Aho, Eija; Oksala, Riikka; Westermarck, Jukka; Mäkelä, Sari; Poutanen, Matti; Aittokallio, Tero

    2016-01-01

    Recent reports have called into question the reproducibility, validity and translatability of the preclinical animal studies due to limitations in their experimental design and statistical analysis. To this end, we implemented a matching-based modelling approach for optimal intervention group allocation, randomization and power calculations, which takes full account of the complex animal characteristics at baseline prior to interventions. In prostate cancer xenograft studies, the method effectively normalized the confounding baseline variability, and resulted in animal allocations which were supported by RNA-seq profiling of the individual tumours. The matching information increased the statistical power to detect true treatment effects at smaller sample sizes in two castration-resistant prostate cancer models, thereby leading to saving of both animal lives and research costs. The novel modelling approach and its open-source and web-based software implementations enable the researchers to conduct adequately-powered and fully-blinded preclinical intervention studies, with the aim to accelerate the discovery of new therapeutic interventions. PMID:27480578

  19. A case study of collaborative facilities use in engineering design

    NASA Astrophysics Data System (ADS)

    Monroe, Laura; Pugmire, David

    2010-01-01

    In this paper we describe the use of visualization tools and facilities in the collaborative design of a replacement weapons system, the Reliable Replacement Warhead (RRW). We used not only standard collaboration methods but also a range of visualization software and facilities to bring together domain specialists from laboratories across the country to collaborate on the design and integrate this disparate input early in the design. This was the first time in U.S. weapons history that a weapon had been designed in this collaborative manner. Benefits included projected cost savings, design improvements and increased understanding across the project.

  20. A case study of collaborative facilities in engineering design

    SciTech Connect

    Monroe, Laura M; Pugmire, David

    2008-01-01

    In this paper we describe the use of visualization tools and facilities in the collaborative design of a replacement weapons system, the Reliable Replacement Warhead (RRW). We used not only standard collaboration methods but also a range of visualization software and facilities to bring together domain specialists from laboratories across the country to collaborate on the design and integrate this disparate input early in the design. This was the first time in U.S. weapons history that a weapon had been designed in this collaborative manner. Benefits included projected cost savings, design improvements and increased understanding across the project.

  1. The Oxford Conception Study design and recruitment experience.

    PubMed

    Pyper, Cecilia; Bromhall, Lise; Dummett, Sarah; Altman, Douglas G; Brownbill, Pat; Murphy, Michael

    2006-11-01

    The Oxford Conception Study is a randomised controlled trial that aims to determine whether or not information about potential fertility from a device that monitors urinary hormones will increase the conception rate in women wishing to conceive. Three modified versions of a fertility monitor have been developed for the study. The monitor measures the levels of urinary oestrone-3-glucuronide (E3G) and luteinising hormone (LH), and the display indicates high or low fertility. The monitor requests all women to test their urine from day 6 to day 25 of the menstrual cycle inclusive. One-third of women are randomised to receive information from the fertility monitor about the early fertile time (from the first rise in E3G until the LH surge is detected), one-third receive information about the late fertile time (the onset of the LH surge and the following 2 days), and a third do not receive any information (control group). All the women are followed up for 6 months or until they are pregnant. A total of 1453 women have been recruited into the study, reaching the study recruitment goal for 80% power to detect a 10% difference in three-cycle pregnancy rate between the Late Fertile Time group (50%) and the Control group (40%), allowing for a 15% non-pregnancy drop-out rate. Follow-up of the women is currently ongoing. The primary analysis will compare the cumulative three-cycle pregnancy rate between each of the study arms. Time-specific conception probabilities will be estimated from coitus information recorded in 12-h intervals. The data from this study will also allow many additional questions to be addressed, including changes in intercourse patterns with feedback about the fertile days and other questions in relation to menstrual cycle function, sexual intercourse, stress, exposures to tobacco products, alcohol, caffeine and medications, fertility and pregnancy outcomes. In addition to presenting the study design, we review the recruitment experience for the Oxford

  2. A Study Investigating Indian Middle School Students' Ideas of Design and Designers

    ERIC Educational Resources Information Center

    Ara, Farhat; Chunawala, Sugra; Natarajan, Chitra

    2011-01-01

    This paper reports on an investigation into middle school students' naive ideas about, and attitudes towards design and designers. The sample for the survey consisted of students from Classes 7 to 9 from a school located in Mumbai. The data were analysed qualitatively and quantitatively to look for trends in students' responses. Results show that…

  3. Which Events Can Cause Iteration in Instructional Design? An Empirical Study of the Design Process

    ERIC Educational Resources Information Center

    Verstegen, D. M. L.; Barnard, Y. F.; Pilot, A.

    2006-01-01

    Instructional design is not a linear process: designers have to weigh the advantages and disadvantages of alternative solutions, taking into account different kinds of conflicting and changing constraints. To make sure that they eventually choose the most optimal one, they have to keep on collecting information, reconsidering continuously whether…

  4. Rationale, design and methods of the CASHMERE study.

    PubMed

    Simon, Tabassome; Boutouyrie, Pierre; Gompel, Anne; Christin-Maitre, Sophie; Laurent, Stéphane; Thuillez, Christian; Zannad, Faiez; Bernaud, Corine; Jaillon, Patrice

    2004-02-01

    Carotid intima-media thickness (IMT) measurement is a noninvasive method used for quantification of early stage of atherosclerosis. Data suggest that the combination of statin and hormone replacement therapy (HRT) might be useful in reducing the early progression of atherosclerosis in postmenopausal women. The main aim of the study is to compare the effects of 12-month therapy with atorvastatin (80 mg/day), HRT (oral 17beta-estradiol 1 or 2 mg/day, plus cyclic dydrogesterone 10 mg) alone and their combination vs. placebo on the progression of carotid IMT by using a high-definition echotracking device. The secondary objectives are to assess the effects of the treatments vs. placebo on arterial stiffness, lipid profile and C-reactive protein. The CASHMERE trial is an European randomized study with a 2 x 2-factorial design, double blinded for atorvastatin and prospective randomized, open blinded endpoint evaluation (PROBE) method applied to HRT. The investigators can adjust the dose of estradiol at any time during follow-up if necessary. A total of 800 postmenopausal women with mild hypercholesterolemia and with no previous history of cardiovascular disease will be included and followed up by their physicians [general practitioners (GPs) or gynecologists] for 1 year. The CASHMERE trial is the first randomized clinical trial to examine the effects of a statin alone or combined with HRT on the structure and the function of carotid artery as early markers of atherosclerosis in postmenopausal women with mild hypercholesterolemia. The results are expected for 2007.

  5. Thermal Protection System design studies for lunar crew module

    NASA Technical Reports Server (NTRS)

    Williams, S. D.; Curry, Donald M.; Bouslog, Stanley A.; Rochelle, William C.

    1993-01-01

    The results of a study to predict aeroheating and Thermal Protection System (TPS) requirements for manned entry vehicles returning to Earth from the moon are presented. The effects of vehicle size and lunar-return strategies on the aerothermodynamic environment and TPS design were assessed. Study guidelines were based on an Apollo Command Module (CM) configuration and lunar return strategies included direct entry and aerocapture followed by Low Earth Orbit entry (LEO). Convective heating was obtained by the boundary layer integral matrix procedure (BLIMP) code, and radiative heating was computed with the QRAD program. The AESOP-STAB code and the AESOP-THERM code were used for TPS analysis for ablating materials and nonablating materials respectively. Results indicated that there was an optimum size for minimum heating and that direct entry had higher heating rates than aerocapture. Aerocapture resulted in higher heat loads and TPS weight. The TPS weight factor was 6-8 percent for all lunar return strategies, with the TPS weight being about 50 percent less than that of the original Apollo CM vehicle.

  6. Flexible missile autopilot design studies with PC-MATLAB/386

    NASA Technical Reports Server (NTRS)

    Ruth, Michael J.

    1989-01-01

    Development of a responsive, high-bandwidth missile autopilot for airframes which have structural modes of unusually low frequency presents a challenging design task. Such systems are viable candidates for modern, state-space control design methods. The PC-MATLAB interactive software package provides an environment well-suited to the development of candidate linear control laws for flexible missile autopilots. The strengths of MATLAB include: (1) exceptionally high speed (MATLAB's version for 80386-based PC's offers benchmarks approaching minicomputer and mainframe performance); (2) ability to handle large design models of several hundred degrees of freedom, if necessary; and (3) broad extensibility through user-defined functions. To characterize MATLAB capabilities, a simplified design example is presented. This involves interactive definition of an observer-based state-space compensator for a flexible missile autopilot design task. MATLAB capabilities and limitations, in the context of this design task, are then summarized.

  7. A case study of collaborative facilities use in engineering design

    SciTech Connect

    Monroe, Laura M

    2009-01-01

    In this paper we describe the use of visualization tools and facilities in the collaborative design of a replacement weapons system, the Reliable Replacement Warhead. We used not only standard collaboration methods but also a range of visualization software and facilities to bring together domain specialists from laboratories across the country to collaborate on the design and integrate this disparate input early in the design.

  8. Use of charging control guidelines for geosynchronous satellite design studies

    NASA Technical Reports Server (NTRS)

    Steves, N. J.

    1980-01-01

    Several of the principle guidelines from the Spacecraft Charging Design Guidelines Handbook are presented with illustrative examples. Use of the geomagnetic substorm specification to qualify satellite designs, the evaluation of satellite designs by using analytical modelling techniques, the use of selected materials and coatings to minimize charging, the tying of all conducting elements to a common ground, and the use of electrical filtering to protect circuits from discharge induced upsets are discussed. Discharge criteria and SCATHA data are excluded.

  9. Deployment of pollution prevention during design -- a case study

    SciTech Connect

    Del Mar, R.A.

    1997-08-15

    Traditionally, pollution prevention (P2) assessments have been performed on existing facilities and ongoing operations, well after the completion of design and construction. It has been theorized that more success can be achieved by moving P2 upstream into the design process, where an estimated 70% of a project`s total life cycle costs are initially fixed. Decisions made during design to prevent or minimize the amount of waste generated can reap benefits for many years to come. This is especially true when designing systems for handling hazardous and radioactive wastes for treatment, storage, and disposal. P2 assessments performed during design of such projects can uncover significant savings to be reaped during project construction, operations, and/or decommissioning. However, many project managers are still reluctant to include some type of P2 review or assessment as part of the design effort, because the immediate payback to the design entity is difficult to quantify. This paper presents the results of a P2 assessment performed on a design project at Hanford which identified close to $500,000 in construction savings while minimizing low-level and mixed radioactive waste generation. This paper describes the process used to per-form the assessment, discusses its results, and provides lessons-learned for future P2 design assessments.

  10. Mariner Jupiter/Saturn 1977 infrared interferometer spectrometer (MJS' 77) design study

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A design study of the Infrared Interferometer Spectrometer and Radiometer (IRIS) instrument for the Mariner Jupiter/Saturn 1977 mission was conducted. The objective of the study was to investigate a number a potential problem areas identified in previous studies and to develop the instrument system designs along the lines providing for the optimum performance obtainable with the allowable budgets. The considerations for the optical design, mechanical design, and electronic design are examined.

  11. Sample Design and Cohort Selection in the Hispanic Community Health Study/Study of Latinos

    PubMed Central

    LaVange, Lisa M.; Kalsbeek, William; Sorlie, Paul D.; Avilés-Santa, Larissa M.; Kaplan, Robert C.; Barnhart, Janice; Liu, Kiang; Giachello, Aida; Lee, David J.; Ryan, John; Criqui, Michael H.; Elder, John P.

    2010-01-01

    PURPOSE The Hispanic Community Health Study (HCHS)/Study of Latinos (SOL) is a multi-center, community based cohort study of Hispanic/Latino adults in the United States. A diverse participant sample is required that is both representative of the target population and likely to remain engaged throughout follow-up. The choice of sample design, its rationale, and benefits and challenges of design decisions are described in this paper. METHODS The study design calls for recruitment and follow-up of a cohort of 16,000 Hispanics/Latinos aged 18-74 years, with 62.5% (10,000) over 44 years of age and adequate subgroup sample sizes to support inference by Hispanic/Latino background. Participants are recruited in community areas surrounding four field centers in the Bronx, Chicago, Miami, and San Diego. A two-stage area probability sample of households is selected with stratification and over-sampling incorporated at each stage to provide a broadly diverse sample, offer efficiencies in field operations, and ensure that the target age distribution is obtained. CONCLUSIONS Embedding probability sampling within this traditional, multi-site cohort study design enables competing research objectives to be met. However, the use of probability sampling requires developing solutions to some unique challenges in both sample selection and recruitment, as described here. PMID:20609344

  12. Rationales, design and recruitment of the Taizhou Longitudinal Study

    PubMed Central

    Wang, Xiaofeng; Lu, Ming; Qian, Ji; Yang, Yajun; Li, Shilin; Lu, Daru; Yu, Shunzhang; Meng, Wei; Ye, Weimin; Jin, Li

    2009-01-01

    Background Rapid economic growth in China in the past decades has been accompanied by dramatic changes in lifestyle and environmental exposures. The burdens of non-communicable diseases, such as cardiovascular diseases, diabetes and cancer, have also increased substantially. Methods/design We initiated a large prospective cohort–the Taizhou Longitudinal Study–in Taizhou (a medium-size city in China) to explore the environmental and genetic risk factors for common non-communicable diseases. The sample size of the cohort will be at least 100,000 adults aged 30–80 years drawn from the general residents of the districts of Hailin, Gaogang, and Taixing (sample frame, 1.8 million) of Taizhou. A three-stage stratified sampling method will be applied. Baseline investigations include interviewer-administered questionnaire, anthropometric measurements, and collection of buccal mucosal cells and blood specimens. DNA will be extracted for genetic studies and serum samples will be used for biochemical examinations. A follow-up survey will be conducted every three years to obtain information on disease occurrence and information on selected lifestyle exposures. Study participants will be followed-up indefinitely by using a chronic disease register system for morbidity and cause-specific mortality. Information on non-fatal events will be obtained for certain major categories of disease (e.g., cancer, stroke, myocardial infarction) through established registry systems. Discussion The Taizhou Longitudinal Study will provide a good basis for exploring the roles of many important environmental factors (especially those concomitant with the economic transformation in China) for common chronic diseases, solely or via interaction with genetic factors. PMID:19589173

  13. Tracking Parkinson’s: Study Design and Baseline Patient Data

    PubMed Central

    Malek, Naveed; Swallow, Diane M.A.; Grosset, Katherine A.; Lawton, Michael A.; Marrinan, Sarah L.; Lehn, Alexander C.; Bresner, Catherine; Bajaj, Nin; Barker, Roger A.; Ben-Shlomo, Yoav; Burn, David J.; Foltynie, Thomas; Hardy, John; Morris, Huw R.; Williams, Nigel M.; Wood, Nicholas; Grosset, Donald G.

    2015-01-01

    Background: There is wide variation in the phenotypic expression of Parkinson’s disease (PD), which is driven by both genetic and epidemiological influences. Objectives: To define and explain variation in the clinical phenotype of PD, in relation to genotypic variation. Methods: Tracking Parkinson’s is a multicentre prospective longitudinal epidemiologic and biomarker study of PD. Patients attending specialist clinics in the United Kingdom with recent onset (<3.5 years) and young onset (diagnosed <50 years of age) PD were enrolled. Motor, non-motor and quality of life assessments were performed using validated scales. Cases are followed up 6 monthly up to 4.5 years for recent onset PD, and up to 1 year for young onset PD. We present here baseline clinical data from this large and demographically representative cohort. Results: 2247 PD cases were recruited (1987 recent onset, 260 young onset). Recent onset cases had a mean (standard deviation, SD) age of 67.6 years (9.3) at study entry, 65.7% males, with disease duration 1.3 years (0.9), MDS-UPDRS 3 scores 22.9 (12.3), LEDD 295 mg/day (211) and PDQ-8 score 5.9 (4.8). Young onset cases were 53.5 years old (7.8) at study entry, 66.9% male, with disease duration 10.2 years (6.7), MDS-UPDRS 3 scores 27.4 (15.3), LEDD 926 mg/day (567) and PDQ-8 score 11.6 (6.1). Conclusions: We have established a large clinical PD cohort, consisting of young onset and recent onset cases, which is designed to evaluate variation in clinical expression, in relation to genetic influences, and which offers a platform for future imaging and biomarker research. PMID:26485428

  14. A robotic wheelchair trainer: design overview and a feasibility study

    PubMed Central

    2010-01-01

    Background Experiencing independent mobility is important for children with a severe movement disability, but learning to drive a powered wheelchair can be labor intensive, requiring hand-over-hand assistance from a skilled therapist. Methods To improve accessibility to training, we developed a robotic wheelchair trainer that steers itself along a course marked by a line on the floor using computer vision, haptically guiding the driver's hand in appropriate steering motions using a force feedback joystick, as the driver tries to catch a mobile robot in a game of "robot tag". This paper provides a detailed design description of the computer vision and control system. In addition, we present data from a pilot study in which we used the chair to teach children without motor impairment aged 4-9 (n = 22) to drive the wheelchair in a single training session, in order to verify that the wheelchair could enable learning by the non-impaired motor system, and to establish normative values of learning rates. Results and Discussion Training with haptic guidance from the robotic wheelchair trainer improved the steering ability of children without motor impairment significantly more than training without guidance. We also report the results of a case study with one 8-year-old child with a severe motor impairment due to cerebral palsy, who replicated the single-session training protocol that the non-disabled children participated in. This child also improved steering ability after training with guidance from the joystick by an amount even greater than the children without motor impairment. Conclusions The system not only provided a safe, fun context for automating driver's training, but also enhanced motor learning by the non-impaired motor system, presumably by demonstrating through intuitive movement and force of the joystick itself exemplary control to follow the course. The case study indicates that a child with a motor system impaired by CP can also gain a short-term benefit

  15. AVID - A design system for technology studies of advanced transportation concepts. [Aerospace Vehicle Interactive Design

    NASA Technical Reports Server (NTRS)

    Wilhite, A. W.; Rehder, J. J.

    1979-01-01

    The basic AVID (Aerospace Vehicle Interactive Design) is a general system for conceptual and preliminary design currently being applied to a broad range of future space transportation and spacecraft vehicle concepts. AVID hardware includes a minicomputer allowing rapid designer interaction. AVID software includes (1) an executive program and communication data base which provide the automated capability to couple individual programs, either individually in an interactive mode or chained together in an automatic sequence mode; and (2) the individual technology and utility programs which provide analysis capability in areas such as graphics, aerodynamics, propulsion, flight performance, weights, sizing, and costs.

  16. NAEP Year 11 Design Efficiency Study. Final Report.

    ERIC Educational Resources Information Center

    Williams, Rick L.; And Others

    The National Assessment of Educational Progress in-school sampling design is a three-stage stratified design. Stratification variables include region, size of community and socioeconomic status. The three levels of sample selection are Primary Sampling Units (PSUs), schools and students. In general, two and sometimes three PSUs are selected from…

  17. Young people, alcohol, and designer drinks: quantitative and qualitative study.

    PubMed Central

    Hughes, K.; MacKintosh, A. M.; Hastings, G.; Wheeler, C.; Watson, J.; Inglis, J.

    1997-01-01

    OBJECTIVE: To examine the appeal of "designer drinks" to young people. DESIGN: Qualitative and quantitative research comprising group discussions and questionnaire led interviews with young people accompanied by a self completion questionnaire. SETTINGS: Argyll and Clyde Health Board area, west Scotland. SUBJECTS: Eight groups aged 12-17 years; 824 aged 12-17 recruited by multistage cluster probability sample from the community health index. RESULTS: Young people were familiar with designer drinks, especially MD 20/20 and leading brands of strong white cider. Attitudes towards these drinks varied quite distinctly with age, clearly reflecting their attitudes towards and motivations for drinking in general. The brand imagery of designer drinks-in contrast with that of more mainstream drinks-matched many 14 and 15 year olds' perceptions and expectations of drinking. Popularity of designer drinks peaked between the ages of 13 and 16 while more conventional drinks showed a consistent increase in popularity with age. Consumption of designer drinks tended to be in less controlled circumstances and was associated with heavier alcohol intake and greater drunkenness. CONCLUSIONS: Designer drinks are a cause for concern. They appeal to young people, often more so than conventional drinks, and are particularly attractive to 14-16 year olds. Consumption of designer drinks is also associated with drinking in less controlled environments, heavier drinking, and greater drunkenness. There is a need for policy debate to assess the desirability of these drinks and the extent to which further controls on their marketing are required. PMID:9040387

  18. A Case Study on the Design of Learning Interfaces

    ERIC Educational Resources Information Center

    Perry, Gabriela Trindade; Schnaid, Fernando

    2012-01-01

    The design of educational software interfaces is a complex task, given its high domain dependency and multidisciplinary nature. It requires that teachers' knowledge and pedagogical beliefs be incorporated into the interface, posing a challenge to both teachers and designers, as they have to act as partners from the earliest phases of the process,…

  19. Optimization of Blocked Designs in fMRI Studies

    ERIC Educational Resources Information Center

    Maus, Barbel; van Breukelen, Gerard J. P.; Goebel, Rainer; Berger, Martijn P. F.

    2010-01-01

    Blocked designs in functional magnetic resonance imaging (fMRI) are useful to localize functional brain areas. A blocked design consists of different blocks of trials of the same stimulus type and is characterized by three factors: the length of blocks, i.e., number of trials per blocks, the ordering of task and rest blocks, and the time between…

  20. Designing Hypercontextualized Games: A Case Study with LieksaMyst

    ERIC Educational Resources Information Center

    Sedano, Carolina Islas; Sutinen, Erkki; Vinni, Mikko; Laine, Teemu H.

    2012-01-01

    Digital technology empowers one to access vast amounts of on-line data. From a learning perspective, however, it is difficult to access meaningful on-site information within a given context. The Hypercontextualized Game (HCG) design model interweaves on-site resources, translated as content, and the digital game. As a local game design process,…

  1. Relating Right Brain Studies to the Design Process.

    ERIC Educational Resources Information Center

    Hofland, John

    Intended for teachers of theatrical design who need to describe a design process for their students, this paper begins by giving a brief overview of recent research that has described the different functions of the right and left cerebral hemispheres. It then notes that although the left hemisphere tends to dominate the right hemisphere, it is the…

  2. The Elements and Principles of Design: A Baseline Study

    ERIC Educational Resources Information Center

    Adams, Erin

    2013-01-01

    Critical to the discipline, both professionally and academically, are the fundamentals of interior design. These fundamentals include the elements and principles of interior design: the commonly accepted tools and vocabulary used to create and communicate successful interior environments. Research indicates a lack of consistency in both the…

  3. The National Lung Screening Trial: overview and study design.

    PubMed

    Aberle, Denise R; Berg, Christine D; Black, William C; Church, Timothy R; Fagerstrom, Richard M; Galen, Barbara; Gareen, Ilana F; Gatsonis, Constantine; Goldin, Jonathan; Gohagan, John K; Hillman, Bruce; Jaffe, Carl; Kramer, Barnett S; Lynch, David; Marcus, Pamela M; Schnall, Mitchell; Sullivan, Daniel C; Sullivan, Dorothy; Zylak, Carl J

    2011-01-01

    The National Lung Screening Trial (NLST) is a randomized multicenter study comparing low-dose helical computed tomography (CT) with chest radiography in the screening of older current and former heavy smokers for early detection of lung cancer, which is the leading cause of cancer-related death in the United States. Five-year survival rates approach 70% with surgical resection of stage IA disease; however, more than 75% of individuals have incurable locally advanced or metastatic disease, the latter having a 5-year survival of less than 5%. It is plausible that treatment should be more effective and the likelihood of death decreased if asymptomatic lung cancer is detected through screening early enough in its preclinical phase. For these reasons, there is intense interest and intuitive appeal in lung cancer screening with low-dose CT. The use of survival as the determinant of screening effectiveness is, however, confounded by the well-described biases of lead time, length, and overdiagnosis. Despite previous attempts, no test has been shown to reduce lung cancer mortality, an endpoint that circumvents screening biases and provides a definitive measure of benefit when assessed in a randomized controlled trial that enables comparison of mortality rates between screened individuals and a control group that does not undergo the screening intervention of interest. The NLST is such a trial. The rationale for and design of the NLST are presented.

  4. Design study for a diverging supernova explosion experiment on NIF

    NASA Astrophysics Data System (ADS)

    Flaig, Markus; Plewa, Tomasz; Keiter, Paul; Grosskopf, Michael; Kuranz, Carolyn; Drake, Paul; Park, Hye-Sook

    2013-10-01

    We report on design simulations of a spherically-diverging, multi-interface, supernova-relevant Rayleigh-Taylor experiment (DivSNRT) to be carried out at the National Ignition Facility (NIF). The simulations are performed in two and three dimensions using the block-adaptive, multi-group radiative diffusion hydrodynamics code CRASH and the FLASH-based MHD code Proteus. In the present study, we concentrate mainly on a planar variant of the experiment. We assess the sensitivity of the Rayleigh-Taylor instability growth on numerical discretization, variations in the laser drive energy and the manufacturing noise at the material interfaces. We find that a simple buoyancy-drag model accurately predicts the mixed-layer width obtained in the simulations. We use synthetic radiographs to optimize the diagnostic system and the experimental setup. Finally, we perform a series of exploratory MHD simulations and investigate the self-generation of magnetic fields and their role in the system evolution. Supported by the DOE grant DE-SC0008823.

  5. Conceptual design study for Infrared Limb Experiment (IRLE)

    NASA Technical Reports Server (NTRS)

    Baker, Doran J.; Ulwick, Jim; Esplin, Roy; Batty, J. C.; Ware, Gene; Tew, Craig

    1989-01-01

    The phase A engineering design study for the Infrared Limb Experiment (IRLE) instrument, the infrared portion of the Mesosphere-Lower Thermosphere Explorer (MELTER) satellite payload is given. The IRLE instrument is a satellite instrument, based on the heritage of the Limb Infrared Monitor of the Stratosphere (LIMS) program, that will make global measurements of O3, CO2, NO, NO2, H2O, and OH from earth limb emissions. These measurements will be used to provide improved understanding of the photochemistry, radiation, dynamics, energetics, and transport phenomena in the lower thermosphere, mesosphere, and stratosphere. The IRLE instrument is the infrared portion of the MELTER satellite payload. MELTER is being proposed to NASA Goddard by a consortium consisting of the University of Michigan, University of Colorado and NASA Langley. It is proposed that the Space Dynamics Laboratory at Utah State University (SDL/USU) build the IRLE instrument for NASA Langley. MELTER is scheduled for launch in November 1994 into a sun-synchronous, 650-km circular orbit with an inclination angle of 97.8 deg and an ascending node at 3:00 p.m. local time.

  6. Neutron tube design study for boron neutron capture therapy application

    SciTech Connect

    Verbeke, J.M.; Lee, Y.; Leung, K.N.; Vujic, J.; Williams, M.D.; Wu, L.K.; Zahir, N.

    1999-05-06

    Radio-frequency (RF) driven ion sources are being developed in Lawrence Berkeley National Laboratory (LBNL) for sealed-accelerator-tube neutron generator application. By using a 5-cm-diameter RF-driven multicusp source H{sup +} yields over 95% have been achieved. These experimental findings will enable one to develop compact neutron generators based on the D-D or D-T fusion reactions. In this new neutron generator, the ion source, the accelerator and the target are all housed in a sealed metal container without external pumping. Recent moderator design simulation studies have shown that 14 MeV neutrons could be moderated to therapeutically useful energy ranges for boron neutron capture therapy (BNCT). The dose near the center of the brain with optimized moderators is about 65% higher than the dose obtained from a typical neutron spectrum produced by the Brookhaven Medical Research Reactor (BMRR), and is comparable to the dose obtained by other accelerator-based neutron sources. With a 120 keV and 1 A deuteron beam, a treatment time of {approx}35 minutes is estimated for BNCT.

  7. Interactive flutter analysis and parametric study for conceptual wing design

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, Vivek

    1995-01-01

    An interactive computer program was developed for wing flutter analysis in the conceptual design stage. The objective was to estimate the flutter instability boundary of a flexible cantilever wing, when well defined structural and aerodynamic data are not available, and then study the effect of change in Mach number, dynamic pressure, torsional frequency, sweep, mass ratio, aspect ratio, taper ratio, center of gravity, and pitch inertia, to guide the development of the concept. The software was developed on MathCad (trademark) platform for Macintosh, with integrated documentation, graphics, database and symbolic mathematics. The analysis method was based on nondimensional parametric plots of two primary flutter parameters, namely Regier number and Flutter number, with normalization factors based on torsional stiffness, sweep, mass ratio, aspect ratio, center of gravity location and pitch inertia radius of gyration. The plots were compiled in a Vaught Corporation report from a vast database of past experiments and wind tunnel tests. The computer program was utilized for flutter analysis of the outer wing of a Blended Wing Body concept, proposed by McDonnell Douglas Corporation. Using a set of assumed data, preliminary flutter boundary and flutter dynamic pressure variation with altitude, Mach number and torsional stiffness were determined.

  8. Experimental design and study of Free Rotor River Turbine

    SciTech Connect

    Nepali, D.B.

    1987-01-01

    Terrace irrigation along the rivers of Nepal is the vital problem of farmers in the remote villages. The existing turbines and irrigation systems are not feasible without civil structures, and suffer from the lack of resources and financial problems. A simple and inexpensive underwater Free Rotor River Turbine (FRRT) which extracts power ranging from a fraction of a HP up to 25 HP from the velocity of the running water in a river or stream was developed. The power obtained from the turbine can be used to run a pump to lift water for drinking purposes and for irrigation along the river banks during the dry season and early part of the wet season. Various designs of models have been tested in the laboratory to find the optimum pitch angle, shape and size of blades, and optimum number of blades in order to accomplish the cheapest, simplest, and most efficient turbine. The effect of diameter of turbine, velocity of water and torque produced by the turbines were studied,and the effect of simple linear twist on blades is discussed.

  9. Design and property study of micro-slot optics

    NASA Astrophysics Data System (ADS)

    Wang, Yuting; Yi, Futing; Zhang, Tianchong; Liu, Jing; Wang, Bo; Zhou, Yue

    2017-03-01

    LIGA (Lithographie Galvanoformung Abformung) as a very useful technique for fabricating devices with micro-scale structures has been reported to make the micro-pore optics (MPO) for years. Light weight is one of the advantages of MPO, making it an alternative for X-ray focusing lenses used on space telescopes. However, researchers seldom considered using the MPO in visible light region. In this article, we designed a micro-slot optics (MSO) similar to MPO and fabricated it by X-ray LIGA technique. The MSO consists of 159 concentric hollow cylinders of nickel with the slot spacings ranging from 59 to 113 μm and the focusing property of MSO is studied by simulations and experiments. Both the simulation and experiment results indicate that MSO is a useful focusing element. The MSO has one focal point when the point source is on the principal optical axis with the size of the focal point equaling to the size of the point source.

  10. Designing climate-smart conservation: guidance and case studies.

    PubMed

    Hansen, Lara; Hoffman, Jennifer; Drews, Carlos; Mielbrecht, Eric

    2010-02-01

    To be successful, conservation practitioners and resource managers must fully integrate the effects of climate change into all planning projects. Some conservation practitioners are beginning to develop, test, and implement new approaches that are designed to deal with climate change. We devised four basic tenets that are essential in climate-change adaptation for conservation: protect adequate and appropriate space, reduce nonclimate stresses, use adaptive management to implement and test climate-change adaptation strategies, and work to reduce the rate and extent of climate change to reduce overall risk. To illustrate how this approach applies in the real world, we explored case studies of coral reefs in the Florida Keys; mangrove forests in Fiji, Tanzania, and Cameroon; sea-level rise and sea turtles in the Caribbean; tigers in the Sundarbans of India; and national planning in Madagascar. Through implementation of these tenets conservation efforts in each of these regions can be made more robust in the face of climate change. Although these approaches require reconsidering some traditional approaches to conservation, this new paradigm is technologically, economically, and intellectually feasible.

  11. Design of laboratory experiments to study radiation-driven implosions

    NASA Astrophysics Data System (ADS)

    Keiter, P. A.; Trantham, M.; Malamud, G.; Klein, S. R.; Davis, J.; VanDervort, R.; Shvarts, D.; Drake, R. P.; Stone, J. M.; Fraenkel, M.; Frank, Y.; Raicher, E.

    2017-03-01

    The interstellar medium is heterogeneous with dense clouds amid an ambient medium. Radiation from young OB stars asymmetrically irradiate the dense clouds. Bertoldi (1989) developed analytic formulae to describe possible outcomes of these clouds when irradiated by hot, young stars. One of the critical parameters that determines the cloud's fate is the number of photon mean free paths in the cloud. For the extreme cases where the cloud size is either much greater than or much less than one mean free path, the radiation transport should be well understood. However, as one transitions between these limits, the radiation transport is much more complex and is a challenge to solve with many of the current radiation transport models implemented in codes. We present the design of laboratory experiments that use a thermal source of x-rays to asymmetrically irradiate a low-density plastic foam sphere. The experiment will vary the density and hence the number of mean free paths of the sphere to study the radiation transport in different regimes. We have developed dimensionless parameters to relate the laboratory experiment to the astrophysical system and we show that we can perform the experiment in the same transport regime.

  12. Astronomy sortie missions definition study. Volume 3, book 2: Appendix: Design analysis and trade studies

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Backup or supporting data for the design analyses and trade studies which defined the astronomy sortie missions are presented. The subjects discussed are: (1) configuration of space shuttle orbiter, (2) electronic subsystems, (3) electric power requirements, and (4) payload requirements. Mathematical models are developed to illustrate the orbital rendezvous capabilities.

  13. The treatment of severe child aggression (TOSCA) study: Design challenges

    PubMed Central

    2011-01-01

    Background Polypharmacy (the concurrent use of more than one psychoactive drug) and other combination interventions are increasingly common for treatment of severe psychiatric problems only partly responsive to monotherapy. This practice and research on it raise scientific, clinical, and ethical issues such as additive side effects, interactions, threshold for adding second drug, appropriate target measures, and (for studies) timing of randomization. One challenging area for treatment is severe child aggression. Commonly-used medications, often in combination, include psychostimulants, antipsychotics, mood stabilizers, and alpha-2 agonists, which vary considerably in terms of perceived safety and efficacy. Results In designing our NIMH-funded trial of polypharmacy, we focused attention on the added benefit of a second drug (risperidone) to the effect of the first (stimulant). We selected these two drugs because their associated adverse events might neutralize each other (e.g., sleep delay and appetite decrease from stimulant versus sedation and appetite increase from antipsychotic). Moreover, there was considerable evidence of efficacy for each drug individually for the management of ADHD and child aggression. The study sample comprised children (ages 6-12 years) with both diagnosed ADHD and disruptive behavior disorder (oppositional-defiant or conduct disorder) accompanied by severe physical aggression. In a staged sequence, the medication with the least problematic adverse effects (stimulant) was openly titrated in 3 weeks to optimal effect. Participants whose behavioral symptoms were not normalized received additional double-blind medication, either risperidone or placebo, by random assignment. Thus children whose behavioral symptoms were normalized with stimulant medication were not exposed to an antipsychotic. All families participated in an empirically-supported parent training program for disruptive behavior, so that the actual comparison was stimulant

  14. Design/cost tradeoff studies. Earth Observatory Satellite system definition study (EOS)

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The results of design/cost tradeoff studies conducted during the Earth Observatory Satellite system definition studies are presented. The studies are concerned with the definition of a basic modular spacecraft capable of supporting a variety of operational and/or research and development missions, with the deployment either by conventional launch vehicles or by means of the space shuttle. The three levels investigated during the study are: (1) subsystem tradeoffs, (2) spacecraft tradeoffs, and (3) system tradeoffs. The range of requirements which the modular concept must span is discussed. The mechanical, thermal, power, data and electromagnetic compatibility aspects of modularity are analyzed. Other data are provided for the observatory design concept, the payloads, integration and test, the ground support equipment, and ground data management systems.

  15. Aerodynamic Design Study of Advanced Multistage Axial Compressor

    NASA Technical Reports Server (NTRS)

    Larosiliere, Louis M.; Wood, Jerry R.; Hathaway, Michael D.; Medd, Adam J.; Dang, Thong Q.

    2002-01-01

    As a direct response to the need for further performance gains from current multistage axial compressors, an investigation of advanced aerodynamic design concepts that will lead to compact, high-efficiency, and wide-operability configurations is being pursued. Part I of this report describes the projected level of technical advancement relative to the state of the art and quantifies it in terms of basic aerodynamic technology elements of current design systems. A rational enhancement of these elements is shown to lead to a substantial expansion of the design and operability space. Aerodynamic design considerations for a four-stage core compressor intended to serve as a vehicle to develop, integrate, and demonstrate aerotechnology advancements are discussed. This design is biased toward high efficiency at high loading. Three-dimensional blading and spanwise tailoring of vector diagrams guided by computational fluid dynamics (CFD) are used to manage the aerodynamics of the high-loaded endwall regions. Certain deleterious flow features, such as leakage-vortex-dominated endwall flow and strong shock-boundary-layer interactions, were identified and targeted for improvement. However, the preliminary results were encouraging and the front two stages were extracted for further aerodynamic trimming using a three-dimensional inverse design method described in part II of this report. The benefits of the inverse design method are illustrated by developing an appropriate pressure-loading strategy for transonic blading and applying it to reblade the rotors in the front two stages of the four-stage configuration. Multistage CFD simulations based on the average passage formulation indicated an overall efficiency potential far exceeding current practice for the front two stages. Results of the CFD simulation at the aerodynamic design point are interrogated to identify areas requiring additional development. In spite of the significantly higher aerodynamic loadings, advanced CFD

  16. Optimal designs for Michaelis-Menten kinetic studies.

    PubMed

    Matthews, J N S; Allcock, G C

    2004-02-15

    Many reactions in enzymology are governed by the Michaelis-Menten equation. Characterising these reactions requires the estimation of the parameters K(M) and V(max) which determine the Michaelis-Menten equation and this is done by observing rates of reactions at a set of substrate concentrations. The choice of substrate concentrations is investigated by determining Bayesian D-optimal designs for a model in which residuals have a normal distribution with constant variance. Designs which focus on alternative quantities, such as K(M) or the ratio V(max)/K(M) are also considered. The effect on the optimal designs of alternative error distributions is also considered.

  17. Design of a Project-Based Study Environment on the World Wide Web.

    ERIC Educational Resources Information Center

    Grooters, Fiona; de Vries, Sjoerd

    This paper presents the design of a project-based study environment on the World Wide Web based upon the e-study concept, i.e., studying by means of Internet technologies. The first section discusses the e-study concept, including Interactive Study Environments (ISE), Interactive Study Systems, and online Study Services. Design guidelines for a…

  18. Simulation study to determine the impact of different design features on design efficiency in discrete choice experiments

    PubMed Central

    Vanniyasingam, Thuva; Cunningham, Charles E; Foster, Gary; Thabane, Lehana

    2016-01-01

    Objectives Discrete choice experiments (DCEs) are routinely used to elicit patient preferences to improve health outcomes and healthcare services. While many fractional factorial designs can be created, some are more statistically optimal than others. The objective of this simulation study was to investigate how varying the number of (1) attributes, (2) levels within attributes, (3) alternatives and (4) choice tasks per survey will improve or compromise the statistical efficiency of an experimental design. Design and methods A total of 3204 DCE designs were created to assess how relative design efficiency (d-efficiency) is influenced by varying the number of choice tasks (2–20), alternatives (2–5), attributes (2–20) and attribute levels (2–5) of a design. Choice tasks were created by randomly allocating attribute and attribute level combinations into alternatives. Outcome Relative d-efficiency was used to measure the optimality of each DCE design. Results DCE design complexity influenced statistical efficiency. Across all designs, relative d-efficiency decreased as the number of attributes and attribute levels increased. It increased for designs with more alternatives. Lastly, relative d-efficiency converges as the number of choice tasks increases, where convergence may not be at 100% statistical optimality. Conclusions Achieving 100% d-efficiency is heavily dependent on the number of attributes, attribute levels, choice tasks and alternatives. Further exploration of overlaps and block sizes are needed. This study's results are widely applicable for researchers interested in creating optimal DCE designs to elicit individual preferences on health services, programmes, policies and products. PMID:27436671

  19. Blade System Design Study. Part II, final project report (GEC).

    SciTech Connect

    Griffin, Dayton A.

    2009-05-01

    As part of the U.S. Department of Energy's Low Wind Speed Turbine program, Global Energy Concepts LLC (GEC)1 has studied alternative composite materials for wind turbine blades in the multi-megawatt size range. This work in one of the Blade System Design Studies (BSDS) funded through Sandia National Laboratories. The BSDS program was conducted in two phases. In the Part I BSDS, GEC assessed candidate innovations in composite materials, manufacturing processes, and structural configurations. GEC also made recommendations for testing composite coupons, details, assemblies, and blade substructures to be carried out in the Part II study (BSDS-II). The BSDS-II contract period began in May 2003, and testing was initiated in June 2004. The current report summarizes the results from the BSDS-II test program. Composite materials evaluated include carbon fiber in both pre-impregnated and vacuum-assisted resin transfer molding (VARTM) forms. Initial thin-coupon static testing included a wide range of parameters, including variation in manufacturer, fiber tow size, fabric architecture, and resin type. A smaller set of these materials and process types was also evaluated in thin-coupon fatigue testing, and in ply-drop and ply-transition panels. The majority of materials used epoxy resin, with vinyl ester (VE) resin also used for selected cases. Late in the project, testing of unidirectional fiberglass was added to provide an updated baseline against which to evaluate the carbon material performance. Numerous unidirectional carbon fabrics were considered for evaluation with VARTM infusion. All but one fabric style considered suffered either from poor infusibility or waviness of fibers combined with poor compaction. The exception was a triaxial carbon-fiberglass fabric produced by SAERTEX. This fabric became the primary choice for infused articles throughout the test program. The generally positive results obtained in this program for the SAERTEX material have led to its being

  20. Study on light weight design of truss structures of spacecrafts

    NASA Astrophysics Data System (ADS)

    Zeng, Fuming; Yang, Jianzhong; Wang, Jian

    2015-08-01

    Truss structure is usually adopted as the main structure form for spacecrafts due to its high efficiency in supporting concentrated loads. Light-weight design is now becoming the primary concern during conceptual design of spacecrafts. Implementation of light-weight design on truss structure always goes through three processes: topology optimization, size optimization and composites optimization. During each optimization process, appropriate algorithm such as the traditional optimality criterion method, mathematical programming method and the intelligent algorithms which simulate the growth and evolution processes in nature will be selected. According to the practical processes and algorithms, combined with engineering practice and commercial software, summary is made for the implementation of light-weight design on truss structure for spacecrafts.

  1. SRB ascent aerodynamic heating design criteria reduction study, volume 2

    NASA Technical Reports Server (NTRS)

    Crain, W. K.; Frost, C. L.; Engel, C. D.

    1989-01-01

    Data are presented for the wind tunnel interference heating factor data base, the timewise tabulated ascent design environments, and the timewise plotted environments comparing the REMTECH results to the Rockwell RI-IVBC-3 results.

  2. Design optimization studies for nonimaging concentrating solar collector tubes

    NASA Astrophysics Data System (ADS)

    Winston, R.; Ogallagher, J. J.

    1983-09-01

    The Integrated Stationary Evacuated Concentrator or ISEC solar collector panel which achieved the best high temperature performance ever measured with a stationary collector was examined. A development effort review and optimize the initial proof of concept design was completed. Changes in the optical design to improve the angular response function and increase the optical efficiency were determined. A recommended profile design with a concentration ratio of 1.55x and an acceptance angle of + - 35(0) was identified. Two alternative panel/module configurations are recommended based on the preferred double ended flow through design. Parasitic thermal and pumping losses show to be reducible to acceptable levels, and two passive approaches to the problem of ensuring stagnation survival are identified.

  3. Very Broad Band VHF/UHF Omnidirectional Antenna Design Study

    DTIC Science & Technology

    1989-12-01

    antennas, is unsuitable for the given appli- cation because its pattern is bi- directional and produces a broad lobe perpendicular to both sides of the...starting point for the new design. The objective was to modify the LPDA to fit the A/V and concurrently achieve a nearly omni- directional radiation pattern...has been included in this review. In particular, many conformal designs including microstrip patch, stripline, slot, and cavity antennas have been

  4. Space shuttle auxiliary propulsion system design study. Executive summary

    NASA Technical Reports Server (NTRS)

    Kelly, P. J.; Schweickert, T. F.

    1972-01-01

    The development and characteristics of an auxiliary propulsion system for space shuttle applications are presented. The system design data necessary for selection of preferred system concepts and the requirements for complementing component design and test programs are analyzed. The use of cryogenic oxygen and hydrogen as a propellant combination is explained on the basis of high vehicle impulse requirements, safety factors, reuse, and logistics considerations. The final configurations for the alternate propellant system, with primary emphasis on earth storable propellants is described.

  5. Multi-Watt Small Radioisotope Thermoelectric Generator Conceptual Design Study

    NASA Astrophysics Data System (ADS)

    Determan, William R.; Otting, William; Frye, Patrick; Abelson, Robert; Ewell, Richard; Miyake, Bob; Synder, Jeff

    2007-01-01

    A need has been identified for a small, light-weight, reliable power source using a radioisotope heat source, to power the next generation of NASA's small surface rovers and exploration probes. Unit performance, development costs, and technical risk are key criteria to be used to select the best design approach. Because safety can be a major program cost and schedule driver, RTG designs should utilize the DOE radioisotope safety program's data base to the maximum extent possible. Other aspects important to the conceptual design include: 1) a multi-mission capable design for atmospheric and vacuum environments, 2) a module size based on one GPHS Step 2 module, 3) use of flight proven thermoelectric converter technologies, 4) a long service lifetime of up to 14 years, 5) maximize unit specific power consistent with all other requirements, and 6) be ready by 2013. Another critical aspect of the design is the thermal integration of the RTG with the rover or probe's heat rejection subsystem and the descent vehicle's heat rejection subsystem. This paper describes two multi-watt RTG design concepts and their integration with a MER-class rover.

  6. Design study of toroidal traction CVT for electric vehicles

    NASA Technical Reports Server (NTRS)

    Raynard, A. E.; Kraus, J.; Bell, D. D.

    1980-01-01

    The development, evaluation, and optimization of a preliminary design concept for a continuously variable transmission (CVT) to couple the high-speed output shaft of an energy storage flywheel to the drive train of an electric vehicle is discussed. An existing computer simulation program was modified and used to compare the performance of five CVT design configurations. Based on this analysis, a dual-cavity full-toroidal drive with regenerative gearing is selected for the CVT design configuration. Three areas are identified that will require some technological development: the ratio control system, the traction fluid properities, and evaluation of the traction contact performance. Finally, the suitability of the selected CVT design concept for alternate electric and hybrid vehicle applications and alternate vehicle sizes and maximum output torques is determined. In all cases the toroidal traction drive design concept is applicable to the vehicle system. The regenerative gearing could be eliminated in the electric powered vehicle because of the reduced ratio range requirements. In other cases the CVT with regenerative gearing would meet the design requirements after appropriate adjustments in size and reduction gearing ratio.

  7. The Bipolar Interactive Psychoeducation (BIPED) study: trial design and protocol

    PubMed Central

    Simpson, Sharon; Barnes, Emma; Griffiths, Emily; Hood, Kerry; Cohen, David; Craddock, Nick; Jones, Ian; Smith, Daniel J

    2009-01-01

    Background Bipolar disorders affect between 3–5% of the population and are associated with considerable lifelong impairment. Since much of the morbidity associated with bipolar disorder is caused by recurrent depressive symptoms, which are often only poorly responsive to antidepressants, there is a need to develop alternative, non-pharmacological interventions. Psychoeducational interventions have emerged as promising long-term therapeutic options for bipolar disorder. Methods/design The study is an exploratory, individually randomised controlled trial. The intervention known as 'Beating Bipolar' is a psychoeducational programme which is delivered via a novel web-based system. We will recruit 100 patients with a diagnosis of DSM-IV bipolar disorder (including type I and type II) currently in clinical remission. The primary outcome is quality of life. This will be compared for those patients who have participated in the psychoeducational programme with those who received treatment as usual. Quality of life will be assessed immediately following the intervention as well as 10 months after randomisation. Secondary outcomes include current depressive and manic symptoms, number of episodes of depression and mania/hypomania experienced during the follow-up period, global functioning, functional impairment and insight. An assessment of costs and a process evaluation will also be conducted which will explore the feasibility and acceptability of the intervention as well as potential barriers to effectiveness. Discussion Bipolar disorder is common, under-recognised and often poorly managed. It is a chronic, life-long, relapsing condition which has an enormous impact on the individual and the economy. This trial will be the first to explore the effectiveness of a novel web-based psychoeducational intervention for patients with bipolar disorder which has potential to be easily rolled out to patients. Trial registration Current Controlled Trials ISRCTN81375447 PMID:19674448

  8. Interpretive Research Aiming at Theory Building: Adopting and Adapting the Case Study Design

    ERIC Educational Resources Information Center

    Diaz Andrade, Antonio

    2009-01-01

    Although the advantages of case study design are widely recognised, its original positivist underlying assumptions may mislead interpretive researchers aiming at theory building. The paper discusses the limitations of the case study design for theory building and explains how grounded theory systemic process adds to the case study design. The…

  9. Development and Formative Evaluation of Multimedia Case Studies for Instructional Design and Technology Students

    ERIC Educational Resources Information Center

    Sugar, William

    2014-01-01

    This study describes the development of three case studies that included a combination of multimedia production and instructional design skills within a particular setting. These case studies incorporated real-life incidents from 47 professional instructional designers. These instructional designers described a total of 146 activities involving…

  10. Design

    ERIC Educational Resources Information Center

    Buchanan, Richard; Cross, Nigel; Durling, David; Nelson, Harold; Owen, Charles; Valtonen, Anna; Boling, Elizabeth; Gibbons, Andrew; Visscher-Voerman, Irene

    2013-01-01

    Scholars representing the field of design were asked to identify what they considered to be the most exciting and imaginative work currently being done in their field, as well as how that work might change our understanding. The scholars included Richard Buchanan, Nigel Cross, David Durling, Harold Nelson, Charles Owen, and Anna Valtonen. Scholars…

  11. Towards an Understanding of Instructional Design Heuristics: An Exploratory Delphi Study

    ERIC Educational Resources Information Center

    York, Cindy S.; Ertmer, Peggy A.

    2011-01-01

    Evidence suggests that experienced instructional designers often use heuristics and adapted models when engaged in the instructional design problem-solving process. This study used the Delphi technique to identify a core set of heuristics designers reported as being important to the success of the design process. The overarching purpose of the…

  12. Mars Orbiter Study. Volume 2: Mission Design, Science Instrument Accommodation, Spacecraft Design

    NASA Technical Reports Server (NTRS)

    Drean, R.; Macpherson, D.; Steffy, D.; Vargas, T.; Shuman, B.; Anderson, K.; Richards, B.

    1982-01-01

    Spacecraft system and subsystem designs were developed at the conceptual level to perform either of two Mars Orbiter Missions, a Climatology Mission and an Aeronomy Mission. The objectives of these missions are to obtain and return data to increase knowledge of Mars.

  13. Strengthening the Regression Discontinuity Design Using Additional Design Elements: A Within-Study Comparison

    ERIC Educational Resources Information Center

    Wing, Coady; Cook, Thomas D.

    2013-01-01

    The sharp regression discontinuity design (RDD) has three key weaknesses compared to the randomized clinical trial (RCT). It has lower statistical power, it is more dependent on statistical modeling assumptions, and its treatment effect estimates are limited to the narrow subpopulation of cases immediately around the cutoff, which is rarely of…

  14. Learning Environments Designed for the Occupants: Three Case Studies of Innovative Elementary School Designs.

    ERIC Educational Resources Information Center

    Shrader-Harvey, Erika; Droge, Martha

    This research project examined how educational facilities are perceived and used by the occupants. It sought to inform the design of effective learning environments in elementary schools through a heightened awareness of the needs of the occupants and an understanding of how they use their school facilities. Project objectives included the…

  15. A study of optimizing processes for metallized textile design application

    NASA Astrophysics Data System (ADS)

    Guo, Ronghui

    The purpose of this research is to find an optimum electroless plating process in order to obtain relatively low surface resistance, and improve functional properties and appearance of nickel-plated and copper-plated polyester fabrics. The optimum results indicate that the NiSO4 concentration and temperature of the bath in the plating process are most important factors influencing surface resistance of electroless nickel-plated polyester fabric. However, NiSO4 concentration and pH of the plating bath are most significant factors affecting electroless copper plating. The micro-structures and properties of nickel and copper, and nickel/copper multi-layer plated polyester fabrics have been studied. In the case of electroless nickel plating, the nickel deposit layer becomes more uniform and continuous when prepared at higher NiSO4 concentration and higher bath temperature. As for the electroless copper plating, the surface morphology of the copper deposits indicates that the average diameter of the particles is increased with the rise of NiSO4 concentration and pH. The surface morphology of nickel/copper multi-layer deposits reveals the presence of ultra-fine nodules and the deposits are compact and uniform in size. There is an increase in EMI SE with respect to the rise of Ni 2+ concentration and bath temperature for electroless nickel plating; and EMI SE increases with the rise of Ni2+ concentration and pH of the plating solution for electroless copper plating on polyester fabric. With the same deposit weight, the EMI SE of nickel/copper-plated fabric is greatly higher than that of the nickel-plated fabric, but slightly lower than that of the copper-plated fabric. However, the anti-corrosive property of nickel/copper-plated fabrics is significantly superior to the copper-plated fabrics, but slightly inferior to the nickel-plated fabric. Design application effects have been explored by the controlling plating conditions. The electroless plating parameters play an

  16. A study of nonlinear flight control system designs

    NASA Astrophysics Data System (ADS)

    Tian, Lijun

    This thesis discusses both normal aircraft flight control where the control surfaces are the primary effectors, and unconventional emergency flight control by engines only. It has long been realized that nonlinearity in aircraft dynamics is a prominent consideration in design of high-performance conventional flight control systems. The engine-only flight control problem also faces strong nonlinearity, although due to different reasons. A nonlinear predictive control method and an approximate receding-horizon control method are used for normal and engine-only flight control system designs for an F-18 aircraft. The comparison of the performance with that of linear flight controllers provides some insight into when nonlinear controllers may render a much improved performance. The concept of nonlinear flight control system design is extended to output tracking control problem. The capability of the nonlinear controller to stabilize the aircraft and accomplish output tracking control for non-minimum phase system is successfully demonstrated. Numerical simulation results of longitudinal motion based on two typical flight conditions for an F-18 aircraft is presented to illustrate some of these aspects. It is suggested in this thesis that nonlinear flight control system design, particularly the engine-only controller design and output tracking control design for non-minimum phase system by using a nonlinear method is more effective for the highly nonlinear environment. The recently developed continuous-time predictive control approach and an approximate receding-horizon control method are shown to be effective methods in the situation while the conventional linear or popular nonlinear control designs are either ineffective or inapplicable.

  17. Technology Solutions Case Study: Hydronic Systems: Designing for Setback Operation

    SciTech Connect

    2014-05-01

    For years, conventional wisdom surrounding space heating has specified two points: size the mechanical systems to the heating loads, and setting the thermostat back at night will result in energy savings. The problem is these two recommendations oppose each other. A system that is properly sized to the heating load will not have the extra capacity necessary to recover from a thermostat setback, especially at design conditions. Properly designing a hydronic system for setback operation can be accomplished but depends on several factors. Determining the appropriateness of setback for a particular project is the first step. This is followed by proper sizing of the boiler and baseboard to ensure the needed capacity can be met. Finally, control settings must be chosen that result in the most efficient and responsive performance. This guide provides step-by-step instructions for heating contractors and hydronic designers for selecting the proper control settings to maximize system performance and improve response time when using a thermostat setback.

  18. Preliminary design studies for the DESCARTES and CIDER codes

    SciTech Connect

    Eslinger, P.W.; Miley, T.B.; Ouderkirk, S.J.; Nichols, W.E.

    1992-12-01

    The Hanford Environmental Dose Reconstruction (HEDR) project is developing several computer codes to model the release and transport of radionuclides into the environment. This preliminary design addresses two of these codes: Dynamic Estimates of Concentrations and Radionuclides in Terrestrial Environments (DESCARTES) and Calculation of Individual Doses from Environmental Radionuclides (CIDER). The DESCARTES code will be used to estimate the concentration of radionuclides in environmental pathways, given the output of the air transport code HATCHET. The CIDER code will use information provided by DESCARTES to estimate the dose received by an individual. This document reports on preliminary design work performed by the code development team to determine if the requirements could be met for Descartes and CIDER. The document contains three major sections: (i) a data flow diagram and discussion for DESCARTES, (ii) a data flow diagram and discussion for CIDER, and (iii) a series of brief statements regarding the design approach required to address each code requirement.

  19. Study design and statistical analysis of data in human population studies with the micronucleus assay.

    PubMed

    Ceppi, Marcello; Gallo, Fabio; Bonassi, Stefano

    2011-01-01

    The most common study design performed in population studies based on the micronucleus (MN) assay, is the cross-sectional study, which is largely performed to evaluate the DNA damaging effects of exposure to genotoxic agents in the workplace, in the environment, as well as from diet or lifestyle factors. Sample size is still a critical issue in the design of MN studies since most recent studies considering gene-environment interaction, often require a sample size of several hundred subjects, which is in many cases difficult to achieve. The control of confounding is another major threat to the validity of causal inference. The most popular confounders considered in population studies using MN are age, gender and smoking habit. Extensive attention is given to the assessment of effect modification, given the increasing inclusion of biomarkers of genetic susceptibility in the study design. Selected issues concerning the statistical treatment of data have been addressed in this mini-review, starting from data description, which is a critical step of statistical analysis, since it allows to detect possible errors in the dataset to be analysed and to check the validity of assumptions required for more complex analyses. Basic issues dealing with statistical analysis of biomarkers are extensively evaluated, including methods to explore the dose-response relationship among two continuous variables and inferential analysis. A critical approach to the use of parametric and non-parametric methods is presented, before addressing the issue of most suitable multivariate models to fit MN data. In the last decade, the quality of statistical analysis of MN data has certainly evolved, although even nowadays only a small number of studies apply the Poisson model, which is the most suitable method for the analysis of MN data.

  20. Study of a Fine Grained Threaded Framework Design

    NASA Astrophysics Data System (ADS)

    Jones, C. D.

    2012-12-01

    Traditionally, HEP experiments exploit the multiple cores in a CPU by having each core process one event. However, future PC designs are expected to use CPUs which double the number of processing cores at the same rate as the cost of memory falls by a factor of two. This effectively means the amount of memory per processing core will remain constant. This is a major challenge for LHC processing frameworks since the LHC is expected to deliver more complex events (e.g. greater pileup events) in the coming years while the LHC experiment's frameworks are already memory constrained. Therefore in the not so distant future we may need to be able to efficiently use multiple cores to process one event. In this presentation we will discuss a design for an HEP processing framework which can allow very fine grained parallelization within one event as well as supporting processing multiple events simultaneously while minimizing the memory footprint of the job. The design is built around the libdispatch framework created by Apple Inc. (a port for Linux is available) whose central concept is the use of task queues. This design also accommodates the reality that not all code will be thread safe and therefore allows one to easily mark modules or sub parts of modules as being thread unsafe. In addition, the design efficiently handles the requirement that events in one run must all be processed before starting to process events from a different run. After explaining the design we will provide measurements from simulating different processing scenarios where the processing times used for the simulation are drawn from processing times measured from actual CMS event processing.

  1. SETI low-frequency feed design study for DSS 24

    NASA Technical Reports Server (NTRS)

    Stanton, P. H.; Lee, P. R.

    1992-01-01

    The Search for Extraterrestrial Intelligence Sky Survey project requires operation from 1 to 10 GHz on the beam waveguide (BWG) antenna DSS 24. The BWG reflectors are undersized in the 1- to 3.02-GHz range, resulting in poor performance. Horn designs and a method for implementing 1- to 3.02-GHz operation on DSS 24 are presented. A combination of a horn and a shaped feed reflector placed above the main reflector is suggested. The horn and feed reflector could be hidden in the RF shadow of the subreflector and struts. Results from computer analysis of this design indicate that adequate performance could be achieved.

  2. Design study for Thermal Infrared Multispectral Scanner (TIMS)

    NASA Technical Reports Server (NTRS)

    Stanich, C. G.; Osterwisch, F. G.; Szeles, D. M.; Houtman, W. H.

    1981-01-01

    The feasibility of dividing the 8-12 micrometer thermal infrared wavelength region into six spectral bands by an airborne line scanner system was investigated. By combining an existing scanner design with a 6 band spectrometer, a system for the remote sensing of Earth resources was developed. The elements in the spectrometer include an off axis reflective collimator, a reflective diffraction grating, a triplet germanium imaging lens, a photoconductive mercury cadmium telluride sensor array, and the mechanical assembly to hold these parts and maintain their optical alignment across a broad temperature range. The existing scanner design was modified to accept the new spectrometer and two field filling thermal reference sources.

  3. Simulation Environment for Orion Launch Abort System Control Design Studies

    NASA Technical Reports Server (NTRS)

    McMinn, J. Dana; Jackson, E. Bruce; Christhilf, David M.

    2007-01-01

    The development and use of an interactive environment to perform control system design and analysis of the proposed Crew Exploration Vehicle Launch Abort System is described. The environment, built using a commercial dynamic systems design package, includes use of an open-source configuration control software tool and a collaborative wiki to coordinate between the simulation developers, control law developers and users. A method for switching between multiple candidate control laws and vehicle configurations is described. Aerodynamic models, especially in a development program, change rapidly, so a means for automating the implementation of new aerodynamic models is described.

  4. Conceptual designs study for a Personnel Launch System (PLS)

    NASA Technical Reports Server (NTRS)

    Wetzel, E. D.

    1990-01-01

    A series of conceptual designs for a manned, Earth to Low Earth Orbit transportation system was developed. Non-winged, low L/D vehicle shapes are discussed. System and subsystem trades emphasized safety, operability, and affordability using near-term technology. The resultant conceptual design includes lessons learned from commercial aviation that result in a safe, routine, operationally efficient system. The primary mission for this Personnel Launch System (PLS) would be crew rotation to the SSF; other missions, including satellite servicing, orbital sortie, and space rescue were also explored.

  5. Laser communication experiment. Volume 1: Design study report: Spacecraft transceiver. Part 3: LCE design specifications

    NASA Technical Reports Server (NTRS)

    1970-01-01

    The requirements for the design, fabrication, performance, and testing of a 10.6 micron optical heterodyne receiver subsystem for use in a laser communication system are presented. The receiver subsystem, as a part of the laser communication experiment operates in the ATS 6 satellite and in a transportable ground station establishing two-way laser communications between the spacecraft and the transportable ground station. The conditions under which environmental tests are conducted are reported.

  6. Designing a Pediatric Study for an Antimalarial Drug by Using Information from Adults

    PubMed Central

    Jullien, Vincent; Samson, Adeline; Guedj, Jérémie; Kiechel, Jean-René; Zohar, Sarah; Comets, Emmanuelle

    2015-01-01

    The objectives of this study were to design a pharmacokinetic (PK) study by using information about adults and evaluate the robustness of the recommended design through a case study of mefloquine. PK data about adults and children were available from two different randomized studies of the treatment of malaria with the same artesunate-mefloquine combination regimen. A recommended design for pediatric studies of mefloquine was optimized on the basis of an extrapolated model built from adult data through the following approach. (i) An adult PK model was built, and parameters were estimated by using the stochastic approximation expectation-maximization algorithm. (ii) Pediatric PK parameters were then obtained by adding allometry and maturation to the adult model. (iii) A D-optimal design for children was obtained with PFIM by assuming the extrapolated design. Finally, the robustness of the recommended design was evaluated in terms of the relative bias and relative standard errors (RSE) of the parameters in a simulation study with four different models and was compared to the empirical design used for the pediatric study. Combining PK modeling, extrapolation, and design optimization led to a design for children with five sampling times. PK parameters were well estimated by this design with few RSE. Although the extrapolated model did not predict the observed mefloquine concentrations in children very accurately, it allowed precise and unbiased estimates across various model assumptions, contrary to the empirical design. Using information from adult studies combined with allometry and maturation can help provide robust designs for pediatric studies. PMID:26711749

  7. [The choice of the type of design in the clinical investigation studies. Case and control studies].

    PubMed

    Posada de la Paz, M

    2004-09-01

    Case-control studies are appropriate designs in neurology sciences to search for risk factors that have already occurred in a group of patients. In them, the subjects are selected on the basis of whether they have the disease or not and then they are compared in regards to the risk factor or prognosis investigated. These sorts of designs can be performed in a shorter and cheaper way than the regular cohort studies. They are appropriate for the evaluation of rare diseases and can examine multiple etiological factors for a single disease. On the contrary, they are not so efficient when rare exposures are involved. Incidence rates in exposed and non-exposed subjects cannot be calculated and on some occasions, the timing between exposure and outcome can be very difficult to establish. The Odds Ratio and its confident intervals is the measurement used for estimating the risk strength in this design. The clinical neurologist should be familiar with these terms, given the frequency of case-control studies described in neurology science literature, and should know their principal advantages and limitations.

  8. Advanced EVA system design requirements study, executive summary

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Design requirements and criteria for the space station advanced Extravehicular Activity System (EVAS) including crew enclosures, portable life support systems, maneuvering propulsion systems, and related EVA support equipment were established. The EVA mission requirements, environments, and medical and physiological requirements, as well as operational, procedures and training issues were considered.

  9. Design study of the deepsky ultraviolet survey telescope. [Spacelab payload

    NASA Technical Reports Server (NTRS)

    Page, N. A.; Callaghan, F. G.; Killen, R. H.; Willis, W.

    1977-01-01

    Preliminary mechanical design and specifications are presented for a wide field ultraviolet telescope and detector to be carried as a Spacelab payload. Topics discussed include support structure stiffness (torsional and bending), mirror assembly, thermal control, optical alignment, attachment to the instrument pointing pallet, control and display, power requirements, acceptance and qualification test plans, cost analysis and scheduling. Drawings are included.

  10. Airport Pavement Test Machine Design and Cost Study

    DTIC Science & Technology

    1993-10-01

    3-3 Total Initial Costs ......................................... 3-4 First Year Operational...assist the FAA in determining the full-scale testing needed to develop and verify the new design procedures The first planning meeting of the working...Douglas Aircraft Company The major conclusion from the first meeting was that full-scale test data must be generated for development and verification

  11. Creativity in Advertising Design Education: An Experimental Study

    ERIC Educational Resources Information Center

    Cheung, Ming

    2011-01-01

    Have you ever thought about why qualities whose definitions are elusive, such as those of a sunset or a half-opened rose, affect us so powerfully? According to de Saussure (Course in general linguistics, 1983), the making of meanings is closely related to the production and interpretation of signs. All types of design, including advertising…

  12. Options Study Documenting the Fast Reactor Fuels Innovative Design Activity

    SciTech Connect

    Jon Carmack; Kemal Pasamehmetoglu

    2010-07-01

    This document provides presentation and general analysis of innovative design concepts submitted to the FCRD Advanced Fuels Campaign by nine national laboratory teams as part of the Innovative Transmutation Fuels Concepts Call for Proposals issued on October 15, 2009 (Appendix A). Twenty one whitepapers were received and evaluated by an independent technical review committee.

  13. Design study for electronic system for Jupiter Orbit Probe (JOP)

    NASA Technical Reports Server (NTRS)

    Elero, B. P., Jr.; Carignan, G. R.

    1978-01-01

    The conceptual design of the Jupiter probe spectrometer is presented. Block and circuit diagrams are presented along with tabulated parts lists. Problem areas are considered to be (1) the schedule, (2) weight limitations for the electronic systems, and (3) radiation hardness of the electronic devices.

  14. PROFILE: Urban Stream Rehabilitation: A Design and Construction Case Study.

    PubMed

    MORRIS; MOSES

    1999-02-01

    / This paper describes the fundamental design features, and construction methods and sequence, of a rehabilitation project on a small suburban creek in Moscow, Idaho, USA. A meandering channel pattern was reestablished for approximately 280 m of straightened, dredged channel, a new floodplain was excavated, and the new riparian zone was replanted. The new stream channel was sized to accommodate an estimated natural bankfull discharge ( approximately 5.6 cms), and floodplain design attempted to match the conveyance of the old enlarged channel (14-20 cms). The project was coordinated by a local nonprofit environmental organization, and the design and construction were tailored to donated materials and a largely volunteer labor force. A high-magnitude flood event (ca. 50-year recurrence interval) six months after construction had no significant impact on the newly constructed channel and revetments, but underscored the need for important detailing of the structures. The use of volunteer labor, while entailing certain benefits, complicates project planning and construction. The most general lesson learned from this project is that sponsoring agencies and clients need to be informed of the many steps and sequencing of properly constructed, complex stream rehabilitation projects as well as the high time and cost requirements for these tasks. KEY WORDS: Stream corridor restoration; Channel design; Streambank revetments

  15. Micro-turbo-generator design and fabrication: A preliminary study

    SciTech Connect

    Wiegele, T.G.

    1996-12-31

    The size and weight of portable electronic products are often dictated by the physical characteristics of the power supply system. The design of energy storage systems is therefore critical to market competitiveness. An alternative to energy storage is proposed in this paper which relies on a very small power generation system which converts a pressure difference in a gas into electrical power: a micro-turbo-generator. The design of the micro-turbo-generator involved combining two very different machines, a micro-generator and a micro-turbine, into a single device which could be fabricated within the constraints of current microelectronic processing techniques. Research into power generation on the micro-scale has begun to take place in the form of electromagnetic micro-motor design and fabrication. These variable reluctance machines can be transformed into power generation devices by implementing accurate rotor position sensing, high-speed current switching and a means for inducing rotor motion. This leads to the implementation of a switched reluctance generator, which is well-understood on the macro-scale but has not been attempted on the micro-scale. The most significant hurdle facing researchers is the task of coupling a prime mover, such as a micro-turbine, to the rotor of a power generation device efficiently and effectively while maintaining relative simplicity in the fabrication procedures. The design presented here offers a potential solution to this problem.

  16. Five Principles for MOOC Design: With a Case Study

    ERIC Educational Resources Information Center

    Drake, John R.; O'Hara, Margaret; Seeman, Elaine

    2015-01-01

    New web technologies have enabled online education to take on a massive scale, prompting many universities to create massively open online courses (MOOCs) that take advantage of these technologies in a seemingly effortless manner. Designing a MOOC, however, is anything but trivial. It involves developing content, learning activities, and…

  17. Design study of a superconducting gantry for carbon beam therapy

    NASA Astrophysics Data System (ADS)

    Kim, J.; Yoon, M.

    2016-09-01

    This paper describes beam-optics design of a gantry for carbon ions in cancer therapy accelerators. A compact design is important for such a gantry. The designed gantry is compact such that its size is comparable to the size of the existing proton gantries. This is made possible by introducing superconducting double helical coils for dipole magnets. The gantry optics is designed in such a way that it provides rotation-invariant optics, a variable beam size, and point-to-parallel scanning of a beam. For large-aperture magnet, a three-dimensional magnetic field distribution is obtained by invoking a computer code, and a number of particles are tracked by integrating equations of motion numerically together with a three-dimensional interpolation. The beam-shape distortion due to the fringe field is reduced to an acceptable level by optimizing the coil windings with the help of a genetic algorithm. Higher-order transfer coefficients are calculated and shown to be reduced greatly with appropriate optimization of the coil windings.

  18. A study of spaceraft technology and design concepts, volume 1

    NASA Technical Reports Server (NTRS)

    Zylius, F. A.

    1985-01-01

    Concepts for advancing the state of the art in the design of unmanned spacecraft, the requirements that gave rise to its configuration, and the programs of technology that are suggested as leading to its eventual development are examined. Particular technology issues discussed include: structures and materials; thermal control; propulsion; electrical power; communications; data management; and guidance, navigation, and control.

  19. A design study of hydrazine and biowaste resistojets

    NASA Technical Reports Server (NTRS)

    Page, R. J.; Stoner, W. A.; Barker, L.

    1986-01-01

    A generalized modeling program was adapted in BASIC on a personal computer to compare the performance of four types of biowaste resistojets and two types of hydrazine augmenters. Analyzed biowaste design types were: (1) an electrically conductive ceramic heater-exchanger of zirconia; (2) a truss heater of platinum in cross flow; (3) an immersed bicoiled tubular heater-exchanger; and (4) a nonexposed, refractory metal, radiant heater in a central cavity within a heat exchanger case. Concepts 2 and 3 are designed to have an efficient, stainless steel outer pressure case. The hydrazine design types are: (5) an immersed bicoil heater exchanger and (6) a nonexposed radiant heater now with a refractory metal case. The ceramic biowaste resistojet has the highest specific impulse growth potential at 2000 K of 192.5 (CO2) and 269 s (H2O). The bicoil produces the highest augmenter temperature of 1994 K for a 2073 K heater giving 317 s at .73 overall efficiency. Detailed temperature profiles of each of the designs are shown. The scaled layout drawings of each are presented with recommended materials and fabrication methods.

  20. Multi-Protocol LAN Design and Implementation: A Case Study.

    ERIC Educational Resources Information Center

    Hazari, Sunil

    1995-01-01

    Reports on the installation of a local area network (LAN) at East Carolina University. Topics include designing the network; computer labs and electronic mail; Internet connectivity; LAN expenses; and recommendations on planning, equipment, administration, and training. A glossary of networking terms is also provided. (AEF)

  1. Gear Crack Propagation Path Studies-- Guidelines Developed for Ultrasafe Design

    NASA Technical Reports Server (NTRS)

    Lewicki, David G.

    2002-01-01

    Effective gear designs balance strength, durability, reliability, size, weight, and cost. However, unexpected gear failures may occur even with adequate gear tooth design. To design an extremely safe system, the designer must ask and address the question "What happens when a failure occurs?" With regard to gear-tooth bending fatigue, tooth or rim fractures may occur. For aircraft, a crack that propagated through a rim would be catastrophic, leading to the disengagement of a rotor or propeller, the loss of an aircraft, and possible fatalities. This failure mode should be avoided. However, a crack that propagated through a tooth might or might not be catastrophic, depending on the design and operating conditions. Also, early warning of this failure mode might be possible because of advances in modern diagnostic systems. An analysis was performed at the NASA Glenn Research Center to develop design guidelines to prevent catastrophic rim fracture failure modes in the event of gear-tooth bending fatigue. The finite element method was used with principles of linear elastic fracture mechanics. Crack propagation paths were predicted for a variety of gear tooth and rim configurations. The effects of rim and web thicknesses, initial crack locations, and gear-tooth geometry factors such as diametral pitch, number of teeth, pitch radius, and tooth pressure angle were considered. Design maps of tooth and rim fracture modes, including the effects of gear geometry, applied load, crack size, and material properties were developed. The occurrence of rim fractures significantly increased as the backup ratio (rim thickness divided by tooth height) decreased. The occurrence of rim fractures also increased as the initial crack location was moved down the root of the tooth. Increased rim and web compliance increased the occurrence of rim fractures. For gears with constant-pitch radii, coarser-pitch teeth increased the occurrence of tooth fractures over rim fractures. Also, 25 degree

  2. The active comparator, new user study design in pharmacoepidemiology: historical foundations and contemporary application.

    PubMed

    Lund, Jennifer L; Richardson, David B; Stürmer, Til

    2015-12-01

    Better understanding of biases related to selective prescribing of, and adherence to, preventive treatments has led to improvements in the design and analysis of pharmacoepidemiologic studies. One influential development has been the "active comparator, new user" study design, which seeks to emulate the design of a head-to-head randomized controlled trial. In this review, we first discuss biases that may affect pharmacoepidemiologic studies and describe their direction and magnitude in a variety of settings. We then present the historical foundations of the active comparator, new user study design and explain how this design conceptually mitigates biases leading to a paradigm shift in pharmacoepidemiology. We offer practical guidance on the implementation of the study design using administrative databases. Finally, we provide an empirical example in which the active comparator, new user study design addresses biases that have previously impeded pharmacoepidemiologic studies.

  3. Optical design study of the Wide Field Survey Telescope (WFST)

    NASA Astrophysics Data System (ADS)

    Lou, Zheng; Liang, Ming; Yao, Dazhi; Zheng, Xianzhong; Cheng, Jingquan; Wang, Hairen; Liu, Wei; Qian, Yuan; Zhao, Haibin; Yang, Ji

    2016-10-01

    WFST is a proposed 2.5m wide field survey telescope intended for dedicated wide field sciences. The telescope is to operate at six wavelength bands (u, g, r, i, z, and w), spanning from 320 to 1028 nm. Designed with a field of view diameter of 3 degree and an effective aperture diameter of 2.29 m, the WFST acquires a total optical throughput over 29.3 m2deg2. With such a large throughput, WFST will survey up to 6000deg2 of the northern sky in multiple colors each night, reaching 23th magnitude for high-precision photometry and astrometry. The optical design is based on an advanced primary-focus system made up of a 2.5 m f/2.48 concave primary mirror and a primary-focus assembly (PFA) consisting of five corrector lenses, atmospheric dispersion corrector (ADC), filters, and the focal-plane instrument. For zenith angles from 0 to 60 degrees, 80% of the polychromatic diffracted energy falls within a 0.35 arcsec diameter. The optical design also highlights an enhanced transmission in the UV bands. The total optical transmission reaches 23.5% at 320 nm, allowing unique science goals in the U band. Other features include low distortion and ease of baffling against stray lights, etc. The focal-plane instrument is a 0.9 gigapixel mosaic CCD camera comprising 9 pieces of 10K×10K CCD chips. An active optics system (AOS) is used to maintain runtime image quality. Various design aspects of the WFST including the optical design, active optics, mirror supports, and the focal-plane instrument are discussed in detail.

  4. Design and Construction Process of Two LEED Certified University Buildings: A Collective Case Study

    ERIC Educational Resources Information Center

    Rich, Kim

    2011-01-01

    This study was conducted at the early stages of integrating LEED into the design process in which a clearer understanding of what sustainable and ecological design was about became evident through the duration of designing and building of two academic buildings on a university campus. In this case study, due to utilizing a grounded theory…

  5. What are you trying to learn? Study designs and the appropriate analysis for your research question

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One fundamental necessity in the entire process of a well-performed study is the experimental design. A well-designed study can help researchers understand and have confidence in their results and analyses, and additionally the agreement or disagreement with the stated hypothesis. This well-designed...

  6. Conceptual design studies of 1985 commercial VTOL transports that utilized rotors, Volume 2

    NASA Technical Reports Server (NTRS)

    Magee, J. P.; Clark, R.; Alexander, H. R.

    1974-01-01

    Results of conceptual design studies of tilt rotor and tandem helicopter aircraft for a 200 nautical mile commercial short haul transport mission are presented. The trade study data used in selecting the design point aircraft and technology details necessary to support the design conclusions are included.

  7. Salton Sea Solar Pond Power Plant Design Study and Regional Applicability

    NASA Technical Reports Server (NTRS)

    French, R. L.

    1984-01-01

    Ormat collected and organized the data base and conducted conceptual plant design, performance, and cost analysis. JPL conducted site-specific studies related to solar pond chemistry, soil biological activity, and dike design and construction. WESTEC conducted environmental investigation studies and performed an environmental assessment. SCE provided planning support for licensing and permitting and technical evaluations of the system design and cost estimate.

  8. An Empirical Study on Operator Interface Design for Handheld Devices to Control Micro Aerial Vehicles

    DTIC Science & Technology

    2010-10-01

    An Empirical Study on Operator Interface Design for Handheld Devices to Control Micro Aerial Vehicles Ming Hou...Report DRDC Toronto TR 2010-075 October 2010 An Empirical Study on Operator Interface Design for Handheld Devices to...drives the need for a small and light controller which will not hinder a soldier carrying it. This requirement brings an issue of designing an

  9. How to calculate sample size for different study designs in medical research?

    PubMed

    Charan, Jaykaran; Biswas, Tamoghna

    2013-04-01

    Calculation of exact sample size is an important part of research design. It is very important to understand that different study design need different method of sample size calculation and one formula cannot be used in all designs. In this short review we tried to educate researcher regarding various method of sample size calculation available for different study designs. In this review sample size calculation for most frequently used study designs are mentioned. For genetic and microbiological studies readers are requested to read other sources.

  10. A Parallel Trade Study Architecture for Design Optimization of Complex Systems

    NASA Technical Reports Server (NTRS)

    Kim, Hongman; Mullins, James; Ragon, Scott; Soremekun, Grant; Sobieszczanski-Sobieski, Jaroslaw

    2005-01-01

    Design of a successful product requires evaluating many design alternatives in a limited design cycle time. This can be achieved through leveraging design space exploration tools and available computing resources on the network. This paper presents a parallel trade study architecture to integrate trade study clients and computing resources on a network using Web services. The parallel trade study solution is demonstrated to accelerate design of experiments, genetic algorithm optimization, and a cost as an independent variable (CAIV) study for a space system application.

  11. 77 FR 9946 - Draft Guidance for Industry on Drug Interaction Studies-Study Design, Data Analysis, Implications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-21

    ... HUMAN SERVICES Food and Drug Administration (Formerly Docket No. 2006D-0344) Draft Guidance for Industry on Drug Interaction Studies--Study Design, Data Analysis, Implications for Dosing, and Labeling... entitled ``Drug Interaction Studies--Study Design, Data Analysis, Implications for Dosing, and...

  12. DS-OPTIMAL DESIGNS FOR STUDYING COMBINATIONS OF CHEMICALS USING MULTIPLE FIXED-RATIO RAY EXPERIMENTS

    EPA Science Inventory

    ABSTRACT

    Detecting and characterizing interactions among chemicals is an important environmental issue. Traditional factorial designs become infeasible as the number of compounds under study increases. Ray designs, which reduce the amount of experimental effort, can be...

  13. Block 2 Solid Rocket Motor (SRM) conceptual design study. Volume 1: Appendices

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The design studies task implements the primary objective of developing a Block II Solid Rocket Motor (SRM) design offering improved flight safety and reliability. The SRM literature was reviewed. The Preliminary Development and Validation Plan is presented.

  14. Studies of design parameters for interferometric methane sensors

    NASA Astrophysics Data System (ADS)

    Wykes, John S.; Willett, Martin J.; Croydon, W. F.

    1992-08-01

    Methane detectors based on the absorption of infrared radiation show some promise as the basis of sensitive and accurate industrial instrumentation. Comb filter methods that utilize the vibration-rotation structure of the methane spectrum in an optically efficient manner have recently aroused particular interest in this context. We describe a mathematical model to simulate the behavior of scanning interferometric comb filters in methane detection systems and discuss the use of the model to investigate optimum design parameters for such systems. The behavior of prototype methane detectors based on scanning Fabry-Perot and Mach Zehnder interferometers is briefly reported. Possible techniques for obtaining further improvements in the design of comb filters for methane detection are suggested.

  15. Conceptual design study: Forest Fire Advanced System Technology (FFAST)

    NASA Technical Reports Server (NTRS)

    Nichols, J. D.; Warren, J. R.

    1986-01-01

    An integrated forest fire detection and mapping system that will be based upon technology available in the 1990s was defined. Uncertainties in emerging and advanced technologies related to the conceptual design were identified and recommended for inclusion as preferred system components. System component technologies identified for an end-to-end system include thermal infrared, linear array detectors, automatic georeferencing and signal processing, geosynchronous satellite communication links, and advanced data integration and display. Potential system configuration options were developed and examined for possible inclusion in the preferred system configuration. The preferred system configuration will provide increased performance and be cost effective over the system currently in use. Forest fire management user requirements and the system component emerging technologies were the basis for the system configuration design. A preferred system configuration was defined that warrants continued refinement and development, examined economic aspects of the current and preferred system, and provided preliminary cost estimates for follow-on system prototype development.

  16. Delayed-onset muscle soreness: a pilot study to assess analgesic study design features.

    PubMed

    Singla, Neil; Desjardins, Paul J; Cosca, Evelyn B; Parulan, Cherri; Arriaga, Anne; Poole, Kelly C; Batz, Dan M; Chang, Phoebe D

    2015-06-01

    Based on a thorough review of the available literature in the delayed-onset muscle soreness (DOMS) model, we identified multiple study design characteristics that are considered to be normative in acute pain research but have not been followed in a majority of published DOMS experiments. We designed an analgesic investigation using the DOMS model that both complied with current scientifically accepted standards for the conduct of analgesic studies and demonstrated reasonable assay sensitivity. This randomized, double-blind, placebo-controlled within-subject study compared the efficacy of topical diclofenac sodium 1% with a matching placebo in reducing pain associated with DOMS. After exercise, subjects reporting DOMS received topical diclofenac sodium gel 1% (DSG 1%) applied to one leg and placebo to the other every 6 hours for 48 hours. Pain intensity was assessed at rest, upon standing, and when walking in the 48 hours after initial drug application (T0). The primary end point was the reduction in pain intensity (SPID 24) on walking. Subjects receiving DSG 1% had less pain while walking compared with those receiving placebo at 24 hours (SPID 24 = 34.9 [22.9] and 23.6 [19.4], respectively; P = 0.032). This investigation used experimental techniques that have been vetted in the field of exercise physiology and superimposed techniques that are considered to be best practice in the field of analgesic research. Over time and with the help of colleagues in both fields of study, similar investigations will validate design features that impact the assay sensitivity of analgesic end points in DOMS models. In addition, the study confirmed the analgesic efficacy of topical DSG 1% over placebo in subjects experiencing DOMS.

  17. Delayed-onset muscle soreness: a pilot study to assess analgesic study design features

    PubMed Central

    Singla, Neil; Desjardins, Paul J.; Cosca, Evelyn B.; Parulan, Cherri; Arriaga, Anne; Poole, Kelly C.; Batz, Dan M.; Chang, Phoebe D.

    2015-01-01

    Abstract Based on a thorough review of the available literature in the delayed-onset muscle soreness (DOMS) model, we identified multiple study design characteristics that are considered to be normative in acute pain research but have not been followed in a majority of published DOMS experiments. We designed an analgesic investigation using the DOMS model that both complied with current scientifically accepted standards for the conduct of analgesic studies and demonstrated reasonable assay sensitivity. This randomized, double-blind, placebo-controlled within-subject study compared the efficacy of topical diclofenac sodium 1% with a matching placebo in reducing pain associated with DOMS. After exercise, subjects reporting DOMS received topical diclofenac sodium gel 1% (DSG 1%) applied to one leg and placebo to the other every 6 hours for 48 hours. Pain intensity was assessed at rest, upon standing, and when walking in the 48 hours after initial drug application (T0). The primary end point was the reduction in pain intensity (SPID 24) on walking. Subjects receiving DSG 1% had less pain while walking compared with those receiving placebo at 24 hours (SPID 24 = 34.9 [22.9] and 23.6 [19.4], respectively; P = 0.032). This investigation used experimental techniques that have been vetted in the field of exercise physiology and superimposed techniques that are considered to be best practice in the field of analgesic research. Over time and with the help of colleagues in both fields of study, similar investigations will validate design features that impact the assay sensitivity of analgesic end points in DOMS models. In addition, the study confirmed the analgesic efficacy of topical DSG 1% over placebo in subjects experiencing DOMS. PMID:25633158

  18. Design studies of an aluminum first wall for INTOR

    SciTech Connect

    Powell, J.R.; Fillo, J.A.; Yu, W.S.; Hsieh, S.Y.; Pearlman, H.; Kramer, R.; Franz, E.; Craig, A.; Farrell, K.

    1980-01-01

    Besides the high erosion rates (including evaporation) expected for INTOR, there may also be high heat fluxes to the first wall, e.g., approx. 9 (Case I) to 24 (Case II) W/cm/sup 2/, from two sources - radiation and charge exchange neutrals. There will also be internal heat generation by neutron and gamma deposition. An aluminum first wall design is analyzed, which substantially reduces concerns about survivability of the first wall during INTOR's operating life.

  19. Study of Optimality Criteria in Design of Experiments.

    DTIC Science & Technology

    1980-06-03

    1970). Introduction to Matrix Analysis. 2nd edition, McGraw Hill. 2. Birkhoff, G.(1946). Tres observations sobre el algebra lineal , Univ. nac. Tucuman...Definition 2.1 is a response function criterion, most criteria in design theory are directly related to parameter estimation. Hence the information matrices ...nonincreasing func- tionals § on the set of information matrices rather than the class of convex nondecreasing functionals * on the set of covariance

  20. Photovoltaic subsystem optimization and design tradeoff study. Final report

    SciTech Connect

    Stolte, W.J.

    1982-03-01

    Tradeoffs and subsystem choices are examined in photovoltaic array subfield design, power-conditioning sizing and selection, roof- and ground-mounted structure installation, energy loss, operating voltage, power conditioning cost, and subfield size. Line- and self-commutated power conditioning options are analyzed to determine the most cost-effective technology in the megawatt power range. Methods for reducing field installation of flat panels and roof mounting of intermediate load centers are discussed, including the cost of retrofit installations.