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Sample records for kalimer-600 simplified core

  1. Conceptual design features of the Kalimer-600 sodium cooled fast reactor

    SciTech Connect

    Hahn, Dohee; Kim, Yeong-Il; Kim, Seong-O; Lee, Jae-Han; Lee, Yong-Bum; Jeong, Hae-Yong

    2007-07-01

    An advanced sodium cooled fast reactor concept, KALIMER-600, has been developed by the Korea Atomic Energy Research Institute to satisfy the Gen-IV technology goals of sustainability, safety and reliability, economics and proliferation resistance. The concept enables an efficient utilization of uranium resources and a reduction of the radioactive waste. The core design has been developed with a strong emphasis on a proliferation resistance by adopting a single enrichment fuel without blanket assemblies. In addition, a passive residual heat removal system, shortened intermediate heat-transport system piping and seismic isolation have been realized in the reactor system design as enhancements to its safety and economics. The inherent safety characteristics of the KALIMER-600 design were verified through a safety analysis of its bounding events. The results for various unprotected events imply that the KALIMER-600 design can accommodate all the analyzed ATWS events. This self-regulation capability of the power without a scram is mainly attributed to the inherent reactivity feedback mechanisms implemented in the metal fuel core design and completely passive decay heat removal system. (authors)

  2. Simplified cut core inductor design

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1974-01-01

    Although filter inductor designers have routinely tended to specify molypermalloy powder cores for use in high frequency power converters and pulse-width modulated switching regulators, there are sigificant advantages in specifying C cores and cut toroids fabricated from grain oriented silicon steels which should not be overlooked. Such steel cores can develop flux densities of 1.6 tesla, with useful linearity to 1.2 tesla, whereas molypermalloy cores carrying d.c. current have useful flux density capabilities only to about 0.3 tesla. The use of silicon steel cores thus makes it possible to design more compact cores, and therefore inductors of reduced volume, or conversely to provide greater load capacity in inductors of a given volume. Information is available which makes it possible to obtain quick and close approximations of significant parameters such as size, weight and temperature rise for silicon steel cores for breadboarding. Graphs, nomographs and tables are presented for this purpose, but more complete mathematical derivations of some of the important parameters are also included for a more rigorous treatment.

  3. Simplifying the ELA Common Core; Demystifying Curriculum

    ERIC Educational Resources Information Center

    Schmoker, Mike; Jago, Carol

    2013-01-01

    The English Language Arts (ELA) Common Core State Standards ([CCSS], 2010) could have a transformational effect on American education. Though the process seems daunting, one can begin immediately integrating the essence of the ELA Common Core in every subject area. This article shows how one could implement the Common Core and create coherent,…

  4. Mechanism and characteristics of long period fiber gratings in simplified hollow-core photonic crystal fibers.

    PubMed

    Wu, Zhifang; Wang, Zhi; Liu, Yan-ge; Han, Tingting; Li, Shuo; Wei, Huifeng

    2011-08-29

    We demonstrate the fabrication of high-quality LPFGs in simplified hollow-core photonic crystal fibers, composed of a hollow hexagonal core and six crown-like air holes, using CO2-laser-irradiation method. Theoretical and experimental investigations indicate that the LPFGs are originated from the strong mode-coupling between the LP01 and LP11 core modes. And a dominant physical mechanism for the mode-coupling is experimentally confirmed to be the periodic microbends rather than the deformations of the cross-section or other common factors. In addition, the LPFGs are highly sensitive to strain and nearly insensitive to temperature, and are promising candidates for gas sensors and nonlinear optical devices. PMID:21935098

  5. Simplified Model of Contactless Air-Core Power Alternator and Transfer Using Ideal Superconductor

    NASA Astrophysics Data System (ADS)

    Jin, Jian Xun; Chen, Xiao Yuan

    The feasibility study of a contactless power transfer (CPT) system using high temperature superconducting (HTS) DC windings has been carried out. The analyses on two HTS CPT application schemes with iron-core and air-core loosely-coupled transformer structures indicate that the introduction of HTS DC windings makes the large-current coupling CPT available for improving the transfer power and efficiency, promising for large-power AC and DC contactless loads, and its transfer efficiency almost coincides with efficiency of the cooperated motor. The design considerations and procedures of the HTS CPT system have also been discussed.

  6. Rearchitecting IT: Simplify. Simplify

    ERIC Educational Resources Information Center

    Panettieri, Joseph C.

    2006-01-01

    Simplifying and securing an IT infrastructure is not easy. It frequently requires rethinking years of hardware and software investments, and a gradual migration to modern systems. Even so, writes the author, universities can take six practical steps to success: (1) Audit software infrastructure; (2) Evaluate current applications; (3) Centralize…

  7. Scale Model Test and Transient Analysis of Steam Injector Driven Passive Core Injection System for Innovative-Simplified Nuclear Power Plant

    NASA Astrophysics Data System (ADS)

    Ohmori, Shuichi; Narabayashi, Tadashi; Mori, Michitsugu

    A steam injector (SI) is a simple, compact and passive pump and also acts as a high-performance direct-contact compact heater. This provides SI with capability to serve also as a direct-contact feed-water heater that heats up feed-water by using extracted steam from turbine. Our technology development aims to significantly simplify equipment and reduce physical quantities by applying "high-efficiency SI", which are applicable to a wide range of operation regimes beyond the performance and applicable range of existing SIs and enables unprecedented multistage and parallel operation, to the low-pressure feed-water heaters and emergency core cooling system of nuclear power plants, as well as achieve high inherent safety to prevent severe accidents by keeping the core covered with water (a severe accident-free concept). This paper describes the results of the scale model test, and the transient analysis of SI-driven passive core injection system (PCIS).

  8. All-fiber reflecting temperature probe based on the simplified hollow-core photonic crystal fiber filled with aqueous quantum dot solution.

    PubMed

    Wu, Jian; Yin, Xiaojin; Wang, Wenyuan; Hong, Xueming; Du, Yu; Geng, Youfu; Li, Xuejin

    2016-02-10

    An all-fiber reflecting fluorescent temperature probe is proposed based on the simplified hollow-core photonic crystal fiber (SHC-PCF) filled with an aqueous CdSe/ZnS quantum dot solution. SHC-PCF is an excellent PCF used to fill liquid materials, which has low loss transmission bands in the visible wavelength range and enlarged core sizes. Both end faces of the SHC-PCF were spliced with multimode fiber after filling in order to generate a more stable and robust waveguide structure. The obtained temperature sensitivity dependence of the emission wavelength and the self-referenced intensity are 126.23 pm/°C and -0.007/°C in the temperature range of -10°C-120°C, respectively. PMID:26906361

  9. A simplified model of aerosol scrubbing by a water pool overlying core debris interacting with concrete. Final report

    SciTech Connect

    Powers, D.A.; Sprung, J.L.

    1993-11-01

    A classic model of aerosol scrubbing from bubbles rising through water is applied to the decontamination of gases produced during core debris interactions with concrete. The model, originally developed by Fuchs, describes aerosol capture by diffusion, sedimentation, and inertial impaction. This original model for spherical bubbles is modified to account for ellipsoidal distortion of the bubbles. Eighteen uncertain variables are identified in the application of the model to the decontamination of aerosols produced during core debris interactions with concrete by a water pool of specified depth and subcooling. These uncertain variables include properties of the aerosols, the bubbles, the water and the ambient pressure. Results are analyzed using a nonparametric, order statistical analysis that allows quantitative differentiation of stochastic and phenomenological uncertainty. The sampled values of the decontamination factors are used to construct estimated probability density functions for the decontamination factor at confidence levels of 50%, 90% and 95%. The decontamination factors for pools 30, 50, 100, 200, 300, and 500 cm deep and subcooling levels of 0, 2, 5, 10, 20, 30, 50, and 70{degrees}C are correlated by simple polynomial regression. These polynomial equations can be used to estimate decontamination factors at prescribed confidence levels.

  10. Enhancing the pressure sensitivity of a Fabry-Perot interferometer using a simplified hollow-core photonic crystal fiber with a microchannel

    NASA Astrophysics Data System (ADS)

    Yu, Yongqin; Chen, Xue; Huang, Quandong; Du, Chenlin; Ruan, Shuangchen; Wei, Huifeng

    2015-09-01

    We demonstrate a novel and compact fiber-probe pressure sensor based on a micro-Fabry-Perot interferometer (FPI). The device is fabricated by splicing both ends of a short-section simplified hollow-core photonic crystal fiber (SHC-PCF) with single-mode fibers. Then, a microchannel is drilled by a femtosecond laser micromachining in the SHC-PCF to allow air to diffuse in. The pressure sensing mechanism is based on the dependence of the air refractive index on pressure. We use both theory and experiment to investigate the sensing characteristics. A micro-FPI with a length of 272 μm demonstrates a pressure sensitivity of 4.071 nm/MPa at 1580 nm and a low-temperature sensitivity of 1.1 pm/°C at atmospheric pressure. We further study the temperature cross sensitivity of the sensor under different pressures. The sensor also shows strong stability and good reversibility, and may be potentially used in pressure sensing applications.

  11. Simplifying Blepharoplasty.

    PubMed

    Zoumalan, Christopher I; Roostaeian, Jason

    2016-01-01

    Blepharoplasty remains one of the most common aesthetic procedures performed today. Its popularity stems partly from the ability to consistently make significant improvements in facial aesthetics with a relatively short operation that carries an acceptable risk profile. In this article, the authors attempt to simplify the approach to both upper and lower lid blepharoplasty and provide an algorithm based on the individual findings for any given patient. The recent trend with both upper and lower lid blepharoplasty has been toward greater volume preservation and at times volume augmentation. A simplified approach to upper lid blepharoplasty focuses on removal of excess skin and judicious removal of periorbital fat. Avoidance of a hollow upper sulcus has been emphasized and the addition of volume with either fat grafting or fillers can be considered. Lower lid blepharoplasty can use a transcutaneous or a transconjunctival approach to address herniated fat pads while blending the lid-cheek junction through release of the orbitomalar ligament and volume augmentation with fat (by repositioning and/or grafting) or injectable fillers. Complications with upper lid blepharoplasty are typically minimal, particularly with conservative skin removal and volume preservation techniques. Lower lid blepharoplasty, conversely, can lead to more serious complications, including lid malposition, and therefore should be approached with great caution. Nevertheless, through an algorithmic approach that meets the needs of each individual patient, the approach to blepharoplasty may be simplified with consistent and predictable results. PMID:26710052

  12. Simplified Parallel Domain Traversal

    SciTech Connect

    Erickson III, David J

    2011-01-01

    Many data-intensive scientific analysis techniques require global domain traversal, which over the years has been a bottleneck for efficient parallelization across distributed-memory architectures. Inspired by MapReduce and other simplified parallel programming approaches, we have designed DStep, a flexible system that greatly simplifies efficient parallelization of domain traversal techniques at scale. In order to deliver both simplicity to users as well as scalability on HPC platforms, we introduce a novel two-tiered communication architecture for managing and exploiting asynchronous communication loads. We also integrate our design with advanced parallel I/O techniques that operate directly on native simulation output. We demonstrate DStep by performing teleconnection analysis across ensemble runs of terascale atmospheric CO{sub 2} and climate data, and we show scalability results on up to 65,536 IBM BlueGene/P cores.

  13. Simplified compact containment BWR plant

    SciTech Connect

    Heki, H.; Nakamaru, M.; Tsutagawa, M.; Hiraiwa, K.; Arai, K.; Hida, T.

    2004-07-01

    The reactor concept considered in this paper has a small power output, a compact containment and a simplified BWR configuration with comprehensive safety features. The Compact Containment Boiling Water Reactor (CCR), which is being developed with matured BWR technologies together with innovative systems/components, is expected to prove attractive in the world energy markets due to its flexibility in regard to both energy demands and site conditions, its high potential for reducing investment risk and its safety features facilitating public acceptance. The flexibility is achieved by CCR's small power output of 300 MWe class and capability of long operating cycle (refueling intervals). CCR is expected to be attractive from view point of investment due to its simplification/innovation in design such as natural circulation core cooling with the bottom located short core, internal upper entry control rod drives (CRDs) with ring-type dryers and simplified ECCS system with high pressure containment concept. The natural circulation core eliminates recirculation pumps and the maintenance of such pumps. The internal upper entry CRDs reduce the height of the reactor vessel (RPV) and consequently reduce the height of the primary containment vessel (PCV). The safety features mainly consist of large water inventory above the core without large penetration below the top of the core, passive cooling system by isolation condenser (IC), passive auto catalytic recombiner and in-vessel retention (IVR) capability. The large inventory increases the system response time in the case of design-base accidents, including loss of coolant accidents. The IC suppresses PCV pressure by steam condensation without any AC power. The recombiner decreases hydrogen concentration in the PCV in the case of a severe accident. Cooling the molten core inside the RPV if the core should be damaged by loss of core coolability could attain the IVR. The feasibility of CCR safety system has been confirmed by LOCA

  14. Development of long operating cycle simplified BWR

    SciTech Connect

    Heki, H.; Nakamaru, M.; Maruya, T.; Hiraiwa, K.; Arai, K.; Narabayash, T.; Aritomi, M.

    2002-07-01

    This paper describes an innovative plant concept for long operating cycle simplified BWR (LSBWR) In this plant concept, 1) Long operating cycle ( 3 to 15 years), 2) Simplified systems and building, 3) Factory fabrication in module are discussed. Designing long operating core is based on medium enriched U-235 with burnable poison. Simplified systems and building are realized by using natural circulation with bottom located core, internal CRD and PCV with passive system and an integrated reactor and turbine building. This LSBWR concept will have make high degree of safety by IVR (In Vessel Retention) capability, large water inventory above the core region and no PCV vent to the environment due to PCCS (Passive Containment Cooling System) and internal vent tank. Integrated building concept could realize highly modular arrangement in hull structure (ship frame structure), ease of seismic isolation capability and high applicability of standardization and factory fabrication. (authors)

  15. Stealth Supersymmetry simplified

    NASA Astrophysics Data System (ADS)

    Fan, JiJi; Krall, Rebecca; Pinner, David; Reece, Matthew; Ruderman, Joshua T.

    2016-07-01

    In Stealth Supersymmetry, bounds on superpartners from direct searches can be notably weaker than in standard supersymmetric scenarios, due to suppressed missing energy. We present a set of simplified models of Stealth Supersymmetry that motivate 13 TeV LHC searches. We focus on simplified models within the Natural Supersymmetry framework, in which the gluino, stop, and Higgsino are assumed to be lighter than other superpartners. Our simplified models exhibit novel decay patterns that differ significantly from topologies of the Minimal Supersymmetric Standard Model, with and without R-parity. We determine limits on stops and gluinos from searches at the 8 TeV LHC. Existing searches constitute a powerful probe of Stealth Supersymmetry gluinos with certain topologies. However, we identify simplified models where the gluino can be considerably lighter than 1 TeV. Stops are significantly less constrained in Stealth Supersymmetry than the MSSM, and we have identified novel stop decay topologies that are completely unconstrained by existing LHC searches.

  16. Can Computers Simplify Admissions?

    ERIC Educational Resources Information Center

    Bruker, Robert M.

    1978-01-01

    Based on experience with a simplified admissions concept, Southern Illinois University is satisfied that the admissions process has been made easier for prospective students, high school counselors, and admissions staff. The computer does not make decisions regarding admission of a student, but reduced work loads for everyone concerned. (Author)

  17. Simplified SBLOCA Analysis of AP1000

    SciTech Connect

    Brown, William L.

    2004-07-01

    The AP1000 is a 1000 MWe advanced nuclear power plant design that uses passive safety features such as a multi-stage, automatic depressurization system (ADS) and gravity-driven, safety injection from core make-up tanks (CMTs) and an in-containment refueling water storage tank (IRWST) to mitigate SBLOCA events. The period of most safety significance for AP1000 during a SBLOCA event is typically associated with the actuation of the fourth stage of the ADS and subsequent transition from CMT to IRWST safety injection. As this period of a SBLOCA is generally of a quasi-steady nature, the integral performance of the AP1000 can be understood and evaluated with a simplified model of the reactor vessel, ADS, and safety injection from the CMTs and IRWST. The simplified model of the AP1000 consists of a series of steady state simulations that uses drift flux in the core region and homogeneous treatment of the core exit region including the ADS flow paths to generate a family of core flow demand curves as a function of system pressure (i.e. mass flow required to satisfy core cooling). These core flow demand curves are plotted against passive safety system supply curves from the CMTs and IRWST to demonstrate the adequacy of the integral performance of the AP1000 during the most important phase of a SBLOCA. (author)

  18. 75 FR 81459 - Simplified Proceedings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-28

    ... Simplified Proceedings in certain civil penalty proceedings. 75 FR 28223. The Commission explained that since... simplify the procedures for handling certain civil penalty proceedings. DATES: The final rule takes effect... to deal with that burgeoning caseload, the Commission is considering methods to simplify...

  19. Simplified Vicarious Radiometric Calibration

    NASA Technical Reports Server (NTRS)

    Stanley, Thomas; Ryan, Robert; Holekamp, Kara; Pagnutti, Mary

    2010-01-01

    A measurement-based radiance estimation approach for vicarious radiometric calibration of spaceborne multispectral remote sensing systems has been developed. This simplified process eliminates the use of radiative transfer codes and reduces the number of atmospheric assumptions required to perform sensor calibrations. Like prior approaches, the simplified method involves the collection of ground truth data coincident with the overpass of the remote sensing system being calibrated, but this approach differs from the prior techniques in both the nature of the data collected and the manner in which the data are processed. In traditional vicarious radiometric calibration, ground truth data are gathered using ground-viewing spectroradiometers and one or more sun photometer( s), among other instruments, located at a ground target area. The measured data from the ground-based instruments are used in radiative transfer models to estimate the top-of-atmosphere (TOA) target radiances at the time of satellite overpass. These TOA radiances are compared with the satellite sensor readings to radiometrically calibrate the sensor. Traditional vicarious radiometric calibration methods require that an atmospheric model be defined such that the ground-based observations of solar transmission and diffuse-to-global ratios are in close agreement with the radiative transfer code estimation of these parameters. This process is labor-intensive and complex, and can be prone to errors. The errors can be compounded because of approximations in the model and inaccurate assumptions about the radiative coupling between the atmosphere and the terrain. The errors can increase the uncertainty of the TOA radiance estimates used to perform the radiometric calibration. In comparison, the simplified approach does not use atmospheric radiative transfer models and involves fewer assumptions concerning the radiative transfer properties of the atmosphere. This new technique uses two neighboring uniform

  20. Saturation current spikes eliminated in saturable core transformers

    NASA Technical Reports Server (NTRS)

    Schwarz, F. C.

    1971-01-01

    Unsaturating composite magnetic core transformer, consisting of two separate parallel cores designed so impending core saturation causes signal generation, terminates high current spike in converter primary circuit. Simplified waveform, demonstrates transformer effectiveness in eliminating current spikes.

  1. Revisiting the Simplified Bernoulli Equation

    PubMed Central

    Heys, Jeffrey J; Holyoak, Nicole; Calleja, Anna M; Belohlavek, Marek; Chaliki, Hari P

    2010-01-01

    Background: The assessment of the severity of aortic valve stenosis is done by either invasive catheterization or non-invasive Doppler Echocardiography in conjunction with the simplified Bernoulli equation. The catheter measurement is generally considered more accurate, but the procedure is also more likely to have dangerous complications. Objective: The focus here is on examining computational fluid dynamics as an alternative method for analyzing the echo data and determining whether it can provide results similar to the catheter measurement. Methods: An in vitro heart model with a rigid orifice is used as a first step in comparing echocardiographic data, which uses the simplified Bernoulli equation, catheterization, and echocardiographic data, which uses computational fluid dynamics (i.e., the Navier-Stokes equations). Results: For a 0.93cm2 orifice, the maximum pressure gradient predicted by either the simplified Bernoulli equation or computational fluid dynamics was not significantly different from the experimental catheter measurement (p > 0.01). For a smaller 0.52cm2 orifice, there was a small but significant difference (p < 0.01) between the simplified Bernoulli equation and the computational fluid dynamics simulation, with the computational fluid dynamics simulation giving better agreement with experimental data for some turbulence models. Conclusion: For this simplified, in vitro system, the use of computational fluid dynamics provides an improvement over the simplified Bernoulli equation with the biggest improvement being seen at higher valvular stenosis levels. PMID:21625471

  2. Simplified High-Power Inverter

    NASA Technical Reports Server (NTRS)

    Edwards, D. B.; Rippel, W. E.

    1984-01-01

    Solid-state inverter simplified by use of single gate-turnoff device (GTO) to commutate multiple silicon controlled rectifiers (SCR's). By eliminating conventional commutation circuitry, GTO reduces cost, size and weight. GTO commutation applicable to inverters of greater than 1-kilowatt capacity. Applications include emergency power, load leveling, drives for traction and stationary polyphase motors, and photovoltaic-power conditioning.

  3. 75 FR 28223 - Simplified Proceedings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-20

    ... From the Federal Register Online via the Government Publishing Office ] FEDERAL MINE SAFETY AND HEALTH REVIEW COMMISSION 29 CFR Part 2700 Simplified Proceedings AGENCY: Federal Mine Safety and Health Review Commission. ACTION: Notice of proposed rulemaking. SUMMARY: The Federal Mine Safety and...

  4. Simplifying the Water Poverty Index

    ERIC Educational Resources Information Center

    Cho, Danny I.; Ogwang, Tomson; Opio, Christopher

    2010-01-01

    In this paper, principal components methodology is used to derive simplified and cost effective indexes of water poverty. Using a well known data set for 147 countries from which an earlier five-component water poverty index comprising of "Resources," "Access," "Capacity," "Use" and "Environment" was constructed, we find that a simplified…

  5. Simplifying plasma chemistry via ILDM

    NASA Astrophysics Data System (ADS)

    Rehman, T.; Kemaneci, E.; Graef, W.; van Dijk, J.

    2016-02-01

    A plasma fluid model containing a large number of chemical species and reactions yields a high computational load. One of the methods to overcome this difficulty is to apply Chemical Reduction Techniques as used in combustion engineering. The chemical reduction technique that we study here is ILDM (Intrinsic Lower Dimensional Manifold). The ILDM method is used to simplify an argon plasma model and then a comparison is made with a CRM (Collisional Radiative Model).

  6. A Simplified Adiabatic Compression Apparatus

    NASA Astrophysics Data System (ADS)

    Moloney, Michael J.; McGarvey, Albert P.

    2007-10-01

    Mottmann described an excellent way to measure the ratio of specific heats for air (γ = Cp/Cv) by suddenly compressing a plastic 2-liter bottle. His arrangement can be simplified so that no valves are involved and only a single connection needs to be made. This is done by adapting the plastic cap of a 2-liter plastic bottle so it connects directly to a Vernier Software Gas Pressure Sensor2 and the LabPro3 interface.

  7. Neuron Model with Simplified Memristive Ionic Channels

    NASA Astrophysics Data System (ADS)

    Hegab, Almoatazbellah M.; Salem, Noha M.; Radwan, Ahmed G.; Chua, Leon

    2015-06-01

    A simplified neuron model is introduced to mimic the action potential generated by the famous Hodgkin-Huxley equations by using the genetic optimization algorithm. Comparison with different neuron models is investigated, and it is confirmed that the sodium and potassium channels in our simplified neuron model are made out of memristors. In addition, the channel equations in the simplified model may be adjusted to introduce a simplified memristor model that is in accordance with the theoretical conditions of the memristive systems.

  8. Simplified Model for iLIDS IDD

    NASA Technical Reports Server (NTRS)

    Lewis, James L.

    2010-01-01

    The NASA Docking System (NDS) Project has provided simplified volumetric models for use by potential hosts vehicles to assess vehicle integration. It should be noted that the JSC-65795 NDS Interface Definition Document (IDD) takes precedence over this simplified model. The simplified model serves as a graphical representation only. It is therefore important to state that dimensions and tolerances are to be taken from the IDD document and supersede any measurements derived from the provided simplified model geometry.

  9. Simplifying microbial electrosynthesis reactor design

    PubMed Central

    Giddings, Cloelle G. S.; Nevin, Kelly P.; Woodward, Trevor; Lovley, Derek R.; Butler, Caitlyn S.

    2015-01-01

    Microbial electrosynthesis, an artificial form of photosynthesis, can efficiently convert carbon dioxide into organic commodities; however, this process has only previously been demonstrated in reactors that have features likely to be a barrier to scale-up. Therefore, the possibility of simplifying reactor design by both eliminating potentiostatic control of the cathode and removing the membrane separating the anode and cathode was investigated with biofilms of Sporomusa ovata. S. ovata reduces carbon dioxide to acetate and acts as the microbial catalyst for plain graphite stick cathodes as the electron donor. In traditional ‘H-cell’ reactors, where the anode and cathode chambers were separated with a proton-selective membrane, the rates and columbic efficiencies of microbial electrosynthesis remained high when electron delivery at the cathode was powered with a direct current power source rather than with a potentiostat-poised cathode utilized in previous studies. A membrane-less reactor with a direct-current power source with the cathode and anode positioned to avoid oxygen exposure at the cathode, retained high rates of acetate production as well as high columbic and energetic efficiencies. The finding that microbial electrosynthesis is feasible without a membrane separating the anode from the cathode, coupled with a direct current power source supplying the energy for electron delivery, is expected to greatly simplify future reactor design and lower construction costs. PMID:26029199

  10. Simplifying microbial electrosynthesis reactor design.

    PubMed

    Giddings, Cloelle G S; Nevin, Kelly P; Woodward, Trevor; Lovley, Derek R; Butler, Caitlyn S

    2015-01-01

    Microbial electrosynthesis, an artificial form of photosynthesis, can efficiently convert carbon dioxide into organic commodities; however, this process has only previously been demonstrated in reactors that have features likely to be a barrier to scale-up. Therefore, the possibility of simplifying reactor design by both eliminating potentiostatic control of the cathode and removing the membrane separating the anode and cathode was investigated with biofilms of Sporomusa ovata. S. ovata reduces carbon dioxide to acetate and acts as the microbial catalyst for plain graphite stick cathodes as the electron donor. In traditional 'H-cell' reactors, where the anode and cathode chambers were separated with a proton-selective membrane, the rates and columbic efficiencies of microbial electrosynthesis remained high when electron delivery at the cathode was powered with a direct current power source rather than with a potentiostat-poised cathode utilized in previous studies. A membrane-less reactor with a direct-current power source with the cathode and anode positioned to avoid oxygen exposure at the cathode, retained high rates of acetate production as well as high columbic and energetic efficiencies. The finding that microbial electrosynthesis is feasible without a membrane separating the anode from the cathode, coupled with a direct current power source supplying the energy for electron delivery, is expected to greatly simplify future reactor design and lower construction costs. PMID:26029199

  11. SIMPLIFIED SODIUM GRAPHITE REACTOR SYSTEM

    DOEpatents

    Dickinson, R.W.

    1963-03-01

    This patent relates to a nuclear power reactor comprising a reactor vessel, shielding means positioned at the top of said vessel, means sealing said reactor vessel to said shielding means, said vessel containing a quantity of sodium, a core tank, unclad graphite moderator disposed in said tank, means including a plurality of process tubes traversing said tank for isolating said graphite from said sodium, fuel elements positioned in said process tubes, said core tank being supported in spaced relation to the walls and bottom of said reactor vessel and below the level of said sodium, neutron shielding means positioned adjacent said core tank between said core tank and the walls of said vessel, said neutron shielding means defining an annuiar volume adjacent the inside wall of said reactor vessel, inlet plenum means below said core tank for providing a passage between said annular volume and said process tubes, heat exchanger means removably supported from the first-named shielding means and positioned in said annular volume, and means for circulating said sodium over said neutron shielding means down through said heat exchanger, across said inlet plenum and upward through said process tubes, said last-named means including electromagnetic pumps located outside said vessel and supported on said vessel wall between said heat exchanger means and said inlet plenum means. (AEC)

  12. How Does a Simplified-Sequence Protein Fold?

    PubMed Central

    Guarnera, Enrico; Pellarin, Riccardo; Caflisch, Amedeo

    2009-01-01

    To investigate a putatively primordial protein we have simplified the sequence of a 56-residue α/β fold (the immunoglobulin-binding domain of protein G) by replacing it with polyalanine, polythreonine, and diglycine segments at regions of the sequence that in the folded structure are α-helical, β-strand, and turns, respectively. Remarkably, multiple folding and unfolding events are observed in a 15-μs molecular dynamics simulation at 330 K. The most stable state (populated at ∼20%) of the simplified-sequence variant of protein G has the same α/β topology as the wild-type but shows the characteristics of a molten globule, i.e., loose contacts among side chains and lack of a specific hydrophobic core. The unfolded state is heterogeneous and includes a variety of α/β topologies but also fully α-helical and fully β-sheet structures. Transitions within the denatured state are very fast, and the molten-globule state is reached in <1 μs by a framework mechanism of folding with multiple pathways. The native structure of the wild-type is more rigid than the molten-globule conformation of the simplified-sequence variant. The difference in structural stability and the very fast folding of the simplified protein suggest that evolution has enriched the primordial alphabet of amino acids mainly to optimize protein function by stabilization of a unique structure with specific tertiary interactions. PMID:19751679

  13. How does a simplified-sequence protein fold?

    PubMed

    Guarnera, Enrico; Pellarin, Riccardo; Caflisch, Amedeo

    2009-09-16

    To investigate a putatively primordial protein we have simplified the sequence of a 56-residue alpha/beta fold (the immunoglobulin-binding domain of protein G) by replacing it with polyalanine, polythreonine, and diglycine segments at regions of the sequence that in the folded structure are alpha-helical, beta-strand, and turns, respectively. Remarkably, multiple folding and unfolding events are observed in a 15-micros molecular dynamics simulation at 330 K. The most stable state (populated at approximately 20%) of the simplified-sequence variant of protein G has the same alpha/beta topology as the wild-type but shows the characteristics of a molten globule, i.e., loose contacts among side chains and lack of a specific hydrophobic core. The unfolded state is heterogeneous and includes a variety of alpha/beta topologies but also fully alpha-helical and fully beta-sheet structures. Transitions within the denatured state are very fast, and the molten-globule state is reached in <1 micros by a framework mechanism of folding with multiple pathways. The native structure of the wild-type is more rigid than the molten-globule conformation of the simplified-sequence variant. The difference in structural stability and the very fast folding of the simplified protein suggest that evolution has enriched the primordial alphabet of amino acids mainly to optimize protein function by stabilization of a unique structure with specific tertiary interactions. PMID:19751679

  14. Simplified SIMPs and the LHC

    NASA Astrophysics Data System (ADS)

    Daci, N.; De Bruyn, I.; Lowette, S.; Tytgat, M. H. G.; Zaldivar, B.

    2015-11-01

    The existence of Dark Matter (DM) in the form of Strongly Interacting Massive Particles (SIMPs) may be motivated by astrophysical observations that challenge the classical Cold DM scenario. Other observations greatly constrain, but do not completely exclude, the SIMP alternative. The signature of SIMPs at the LHC may consist of neutral, hadron-like, trackless jets produced in pairs. We show that the absence of charged content can provide a very efficient tool to suppress dijet backgrounds at the LHC, thus enhancing the sensitivity to a potential SIMP signal. We illustrate this using a simplified SIMP model and present a detailed feasibility study based on simulations, including a dedicated detector response parametrization. We evaluate the expected sensitivity to various signal scenarios and tentatively consider the exclusion limits on the SIMP elastic cross section with nucleons.

  15. Simplified Radioimmunoassay for Diagnostic Serology

    PubMed Central

    Hutchinson, Harriet D.; Ziegler, Donald W.

    1972-01-01

    A simplified, indirect radioimmunoassay is described for Escherichia coli, vaccinia virus, and herpesvirus. The antigens were affixed to glass cover slips; thus both the primary and secondary reactions take place on the cover slips, and the unbound antiserum is easily separated from the bound antiserum by rinsing. Rabbit or human immune sera were reacted with the antigens, and the primary immune complex was quantitated by a secondary reaction with 125I-indicator globulin (anti-rabbit or anti-human). A direct relationship between the antiserum concentration and the 125I absorption was established. Variations in titers were detectable, and the titers were comparable to complement fixation titers. Homologous and heterologous reactions were distinguishable. The method affords an objective, quantitative, and qualitative evaluation of antibody, and results are reproducible. PMID:4344958

  16. 48 CFR 453.213 - Simplified Acquisition and other simplified purchase procedures (AD-838).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... other simplified purchase procedures (AD-838). 453.213 Section 453.213 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE CLAUSES AND FORMS FORMS Prescription of Forms 453.213 Simplified Acquisition and other simplified purchase procedures (AD-838). Form AD-838, Purchase Order, is prescribed...

  17. Simplified method for nonlinear structural analysis

    NASA Technical Reports Server (NTRS)

    Kaufman, A.

    1983-01-01

    A simplified inelastic analysis computer program was developed for predicting the stress-strain history of a thermomechanically cycled structure from an elastic solution. The program uses an iterative and incremental procedure to estimate the plastic strains from the material stress-strain properties and a simulated plasticity hardening model. The simplified method was exercised on a number of problems involving uniaxial and multiaxial loading, isothermal and nonisothermal conditions, and different materials and plasticity models. Good agreement was found between these analytical results and nonlinear finite element solutions for these problems. The simplified analysis program used less than 1 percent of the CPU time required for a nonlinear finite element analysis.

  18. Experimental demonstration of simplified quantum process tomography.

    PubMed

    Wu, Z; Li, S; Zheng, W; Peng, X; Feng, M

    2013-01-14

    The essential tool to characterize dynamics of an open quantum system is quantum process tomography (QPT). Although standard QPT methods are hard to be scalable, simplified QPT approach is available if we have the prior knowledge that the system Hamiltonian commutes with the system-environment interaction Hamiltonian. Using a nuclear magnetic resonance (NMR) quantum simulator, we experimentally simulate dephasing channels to demonstrate the simplified QPT as well as the standard QPT method as a comparison. The experimental results agree well with our predictions which confirm the validity and better efficiency of the simplified QPT. PMID:23320694

  19. Composite Cores

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Spang & Company's new configuration of converter transformer cores is a composite of gapped and ungapped cores assembled together in concentric relationship. The net effect of the composite design is to combine the protection from saturation offered by the gapped core with the lower magnetizing requirement of the ungapped core. The uncut core functions under normal operating conditions and the cut core takes over during abnormal operation to prevent power surges and their potentially destructive effect on transistors. Principal customers are aerospace and defense manufacturers. Cores also have applicability in commercial products where precise power regulation is required, as in the power supplies for large mainframe computers.

  20. Simplified two and three dimensional HTTR benchmark problems

    SciTech Connect

    Zhan Zhang; Dingkang Zhang; Justin M. Pounders; Abderrafi M. Ougouag

    2011-05-01

    To assess the accuracy of diffusion or transport methods for reactor calculations, it is desirable to create heterogeneous benchmark problems that are typical of whole core configurations. In this paper we have created two and three dimensional numerical benchmark problems typical of high temperature gas cooled prismatic cores. Additionally, a single cell and single block benchmark problems are also included. These problems were derived from the HTTR start-up experiment. Since the primary utility of the benchmark problems is in code-to-code verification, minor details regarding geometry and material specification of the original experiment have been simplified while retaining the heterogeneity and the major physics properties of the core from a neutronics viewpoint. A six-group material (macroscopic) cross section library has been generated for the benchmark problems using the lattice depletion code HELIOS. Using this library, Monte Carlo solutions are presented for three configurations (all-rods-in, partially-controlled and all-rods-out) for both the 2D and 3D problems. These solutions include the core eigenvalues, the block (assembly) averaged fission densities, local peaking factors, the absorption densities in the burnable poison and control rods, and pin fission density distribution for selected blocks. Also included are the solutions for the single cell and single block problems.

  1. 3. 6 simplified methods for design

    SciTech Connect

    Nickell, R.E.; Yahr, G.T.

    1981-01-01

    Simplified design analysis methods for elevated temperature construction are classified and reviewed. Because the major impetus for developing elevated temperature design methodology during the past ten years has been the LMFBR program, considerable emphasis is placed upon results from this source. The operating characteristics of the LMFBR are such that cycles of severe transient thermal stresses can be interspersed with normal elevated temperature operational periods of significant duration, leading to a combination of plastic and creep deformation. The various simplified methods are organized into two general categories, depending upon whether it is the material, or constitutive, model that is reduced, or the geometric modeling that is simplified. Because the elastic representation of material behavior is so prevalent, an entire section is devoted to elastic analysis methods. Finally, the validation of the simplified procedures is discussed.

  2. Simplified models for LHC new physics searches

    NASA Astrophysics Data System (ADS)

    Alves, Daniele; Arkani-Hamed, Nima; Arora, Sanjay; Bai, Yang; Baumgart, Matthew; Berger, Joshua; Buckley, Matthew; Butler, Bart; Chang, Spencer; Cheng, Hsin-Chia; Cheung, Clifford; Sekhar Chivukula, R.; Cho, Won Sang; Cotta, Randy; D'Alfonso, Mariarosaria; El Hedri, Sonia; Essig (Editor, Rouven; Evans, Jared A.; Fitzpatrick, Liam; Fox, Patrick; Franceschini, Roberto; Freitas, Ayres; Gainer, James S.; Gershtein, Yuri; Gray, Richard; Gregoire, Thomas; Gripaios, Ben; Gunion, Jack; Han, Tao; Haas, Andy; Hansson, Per; Hewett, JoAnne; Hits, Dmitry; Hubisz, Jay; Izaguirre, Eder; Kaplan, Jared; Katz, Emanuel; Kilic, Can; Kim, Hyung-Do; Kitano, Ryuichiro; Koay, Sue Ann; Ko, Pyungwon; Krohn, David; Kuflik, Eric; Lewis, Ian; Lisanti (Editor, Mariangela; Liu, Tao; Liu, Zhen; Lu, Ran; Luty, Markus; Meade, Patrick; Morrissey, David; Mrenna, Stephen; Nojiri, Mihoko; Okui, Takemichi; Padhi, Sanjay; Papucci, Michele; Park, Michael; Park, Myeonghun; Perelstein, Maxim; Peskin, Michael; Phalen, Daniel; Rehermann, Keith; Rentala, Vikram; Roy, Tuhin; Ruderman, Joshua T.; Sanz, Veronica; Schmaltz, Martin; Schnetzer, Stephen; Schuster (Editor, Philip; Schwaller, Pedro; Schwartz, Matthew D.; Schwartzman, Ariel; Shao, Jing; Shelton, Jessie; Shih, David; Shu, Jing; Silverstein, Daniel; Simmons, Elizabeth; Somalwar, Sunil; Spannowsky, Michael; Spethmann, Christian; Strassler, Matthew; Su, Shufang; Tait (Editor, Tim; Thomas, Brooks; Thomas, Scott; Toro (Editor, Natalia; Volansky, Tomer; Wacker (Editor, Jay; Waltenberger, Wolfgang; Yavin, Itay; Yu, Felix; Zhao, Yue; Zurek, Kathryn; LHC New Physics Working Group

    2012-10-01

    This document proposes a collection of simplified models relevant to the design of new-physics searches at the Large Hadron Collider (LHC) and the characterization of their results. Both ATLAS and CMS have already presented some results in terms of simplified models, and we encourage them to continue and expand this effort, which supplements both signature-based results and benchmark model interpretations. A simplified model is defined by an effective Lagrangian describing the interactions of a small number of new particles. Simplified models can equally well be described by a small number of masses and cross-sections. These parameters are directly related to collider physics observables, making simplified models a particularly effective framework for evaluating searches and a useful starting point for characterizing positive signals of new physics. This document serves as an official summary of the results from the ‘Topologies for Early LHC Searches’ workshop, held at SLAC in September of 2010, the purpose of which was to develop a set of representative models that can be used to cover all relevant phase space in experimental searches. Particular emphasis is placed on searches relevant for the first ˜50-500 pb-1 of data and those motivated by supersymmetric models. This note largely summarizes material posted at http://lhcnewphysics.org/, which includes simplified model definitions, Monte Carlo material, and supporting contacts within the theory community. We also comment on future developments that may be useful as more data is gathered and analyzed by the experiments.

  3. Simplified Models for LHC New Physics Searches

    SciTech Connect

    Alves, Daniele; Arkani-Hamed, Nima; Arora, Sanjay; Bai, Yang; Baumgart, Matthew; Berger, Joshua; Buckley, Matthew; Butler, Bart; Chang, Spencer; Cheng, Hsin-Chia; Cheung, Clifford; Chivukula, R.Sekhar; Cho, Won Sang; Cotta, Randy; D'Alfonso, Mariarosaria; El Hedri, Sonia; Essig, Rouven,; Evans, Jared A.; Fitzpatrick, Liam; Fox, Patrick; Franceschini, Roberto; /more authors..

    2012-06-01

    This document proposes a collection of simplified models relevant to the design of new-physics searches at the LHC and the characterization of their results. Both ATLAS and CMS have already presented some results in terms of simplified models, and we encourage them to continue and expand this effort, which supplements both signature-based results and benchmark model interpretations. A simplified model is defined by an effective Lagrangian describing the interactions of a small number of new particles. Simplified models can equally well be described by a small number of masses and cross-sections. These parameters are directly related to collider physics observables, making simplified models a particularly effective framework for evaluating searches and a useful starting point for characterizing positive signals of new physics. This document serves as an official summary of the results from the 'Topologies for Early LHC Searches' workshop, held at SLAC in September of 2010, the purpose of which was to develop a set of representative models that can be used to cover all relevant phase space in experimental searches. Particular emphasis is placed on searches relevant for the first {approx} 50-500 pb{sup -1} of data and those motivated by supersymmetric models. This note largely summarizes material posted at http://lhcnewphysics.org/, which includes simplified model definitions, Monte Carlo material, and supporting contacts within the theory community. We also comment on future developments that may be useful as more data is gathered and analyzed by the experiments.

  4. GE simplified boiling water reactor stability analysis in time domain

    NASA Astrophysics Data System (ADS)

    Lu, Shanlai

    1997-12-01

    General Electric Simplified Boiling Water Reactor (SBWR) was designed as a next generation light water reactor. It uses natural circulation to remove the heat from the reactor core. Because of this unique in-vessel circulation feature, SBWR is expected to exhibit different stability behaviors. The main emphasis of this thesis is to study the SBWR stability behavior in the time domain. The best-estimate BWR accident/transient analysis computer code, TRAC-BF1, is employed to analyze the SBWR stability behavior. A detailed TRAC-BF1 SBWR model has been developed, which has the capability to model the in-vessel natural circulation and the reactor core kinetics. The model is used to simulate three slow depressurization processes. The simulation results show that the reactor is stable under low pressure and nominal downcomer water level conditions. However, when the downcomer water level is raised to about 19.2 m above the bottom of the reactor vessel, an unstable power oscillation is observed. The identified power oscillation is further analyzed using TRAC-BF1 1-D kinetics and the new TRAC-BF1 3-D kinetics code developed in this thesis. The effects of different time step sizes and vessel model nodalizations are examined. It is found that the power oscillation is in-phase and has a frequency of 0.3 HZ. In order to further explore the physical instabilty initiation mechanisms, a simplified dynamic model consisting of six simple differential equations is developed. The simplified model is able to predict the dominant physical phenomenon identified by the TRAC-BF1 analysis. The results indicate that the system instability is possibly caused by the steam separator hydro-static head oscillation under the high water level condition. In order to explore the higher order spacial effect of power oscillation, a 3-D reactor core kinetics code is coupled with the TRAC-BF1 computer code in the PVM parallel processing environment. A new coupling scheme and a multiple time step marching

  5. Simplified models for exotic BSM searches

    NASA Astrophysics Data System (ADS)

    Heisig, Jan; Lessa, Andre; Quertenmont, Loic

    2015-12-01

    Simplified models are a successful way of interpreting current LHC searches for models beyond the standard model (BSM). So far simplified models have focused on topologies featuring a missing transverse energy (MET) signature. However, in some BSM theories other, more exotic, signatures occur. If a charged particle becomes long-lived on collider time scales — as it is the case in parts of the SUSY parameter space — it leads to a very distinct signature. We present an extension of the computer package SModelS which includes simplified models for heavy stable charged particles (HSCP). As a physical application we investigate the CMSSM stau co-annihilation strip containing long-lived staus, which presents a potential solution to the Lithium problem. Applying both MET and HSCP constraints we show that, for low values of tan β, all this region of parameter space either violates Dark Matter constraints or is excluded by LHC searches.

  6. Hypersonic Vehicle Propulsion System Simplified Model Development

    NASA Technical Reports Server (NTRS)

    Stueber, Thomas J.; Raitano, Paul; Le, Dzu K.; Ouzts, Peter

    2007-01-01

    This document addresses the modeling task plan for the hypersonic GN&C GRC team members. The overall propulsion system modeling task plan is a multi-step process and the task plan identified in this document addresses the first steps (short term modeling goals). The procedures and tools produced from this effort will be useful for creating simplified dynamic models applicable to a hypersonic vehicle propulsion system. The document continues with the GRC short term modeling goal. Next, a general description of the desired simplified model is presented along with simulations that are available to varying degrees. The simulations may be available in electronic form (FORTRAN, CFD, MatLab,...) or in paper form in published documents. Finally, roadmaps outlining possible avenues towards realizing simplified model are presented.

  7. A simplified model for glass formation

    NASA Technical Reports Server (NTRS)

    Uhlmann, D. R.; Onorato, P. I. K.; Scherer, G. W.

    1979-01-01

    A simplified model of glass formation based on the formal theory of transformation kinetics is presented, which describes the critical cooling rates implied by the occurrence of glassy or partly crystalline bodies. In addition, an approach based on the nose of the time-temperature-transformation (TTT) curve as an extremum in temperature and time has provided a relatively simple relation between the activation energy for viscous flow in the undercooled region and the temperature of the nose of the TTT curve. Using this relation together with the simplified model, it now seems possible to predict cooling rates using only the liquidus temperature, glass transition temperature, and heat of fusion.

  8. Heavy Flavor Simplified Models at the LHC

    SciTech Connect

    Essig, Rouven; Izaguirre, Eder; Kaplan, Jared; Wacker, Jay G.; /SLAC

    2012-04-03

    We consider a comprehensive set of simplified models that contribute to final states with top and bottom quarks at the LHC. These simplified models are used to create minimal search strategies that ensure optimal coverage of new heavy flavor physics involving the pair production of color octets and triplets. We provide a set of benchmarks that are representative of model space, which can be used by experimentalists to perform their own optimization of search strategies. For data sets larger than 1 fb{sup -1}, same-sign dilepton and 3b search regions become very powerful. Expected sensitivities from existing and optimized searches are given.

  9. Synthesis of a simplified triazole analogue of pateamine A.

    PubMed

    Hemi Cumming, A; Brown, Sarah L; Tao, Xu; Cuyamendous, Claire; Field, Jessica J; Miller, John H; Harvey, Joanne E; Teesdale-Spittle, Paul H

    2016-06-14

    Pateamine A is a naturally occurring metabolite extracted from the marine sponge Mycale hentscheli. It exhibits potent cytotoxicity towards cancer cell lines and has been shown to target protein translation initiation via inhibition of the function of eukaryotic initiation factor 4A proteins. We have synthesised a simplified analogue of pateamine A, consisting of the skeletal core of the natural product but with the thiazole heterocycle replaced by a triazole. The convergent design of the synthesis features a base-induced opening of a δ-valerolactone to access the Z,E-dienoate moiety, Julia-Kocienski olefination and copper-catalysed azide-alkyne cycloaddition. Bioactivity testing of the simplified pateamine A analogue (3) indicated a significant reduction in cytotoxicity, compared to natural pateamine A. We propose that this reduced activity is due mainly to the substitution of the thiazole for the triazole heterocycle. This supports the hypothesis that the thiazole of pateamine A is important for binding to its biological target. PMID:27180995

  10. Angular momentum conservation in a simplified Venus General Circulation Model

    NASA Astrophysics Data System (ADS)

    Lee, C.; Richardson, M. I.

    2012-11-01

    Angular momentum (AM) conservation and transport are critical components of all General Circulation Model (GCM) simulations, and particularly for simulations of the Venus atmosphere. We show that a Venus GCM based upon the Geophysical Fluid Dynamics Laboratory (GFDL) Flexible Modeling System (FMS) GCM conserves angular momentum to better than 2% per 1000 Venus years (≈225,000 Earth days) of integration under the extreme conditions of a simplified Venus simulation with low surface torques. With no topography in the GCM, physical torques due to surface/atmosphere frictional interactions dominate the acceleration of an initially stationary atmosphere and provide more than four times the angular momentum of solid body co-rotation over an integration period of 100 Venus years. During the subsequent steady state period of 200 Venus years negligible mean physical torques cause variation in the total angular momentum of less than 5% and produce a stable multi-century simulation. Diffusion and damping processes within the GCM account for AM losses of less than 0.2% per 1000 Venus years. This study provides a stable comparison point for other GCMs by employing a simplified forcing scheme. The diagnostics and analysis require little or no modification to the core GCM and are sufficiently robust to allow easy model inter-comparison.

  11. Stereocontrolled Synthesis of Key Advanced Intermediates toward Simplified Acetogenin Analogues.

    PubMed

    Le Huérou, Yvan; Doyon, Julien; Grée, René L.

    1999-09-01

    The stereo- and enantiocontrolled synthesis of substituted beta-hydroxy ethers based on glycol and catechol bearing an alkyne group and a series of substituents is reported. These substrates were designed to mimic the bis-THF array of annonaceous acetogenins and to provide an access to simplified and modified analogues. The key steps of the synthesis involve the condensation of the nonracemic mesylate of solketal with ethylene glycol and catechol, followed by an alkylation with a glycidyl derivative. Under appropriate conditions, the reaction is completely stereoselective and allows the synthesis of all the diastereomers. After the epoxide was opened with triethylsilylacetylene, the second epoxide was unmasked and reacted with a series of alkyl, aryl, amine, and alcohol reagents. A series of 28 analogues was prepared having a glycol or a catechol core, a stereodefined configuration of the flanking hydroxyl groups, and an acetylenic appendage suitable for a coupling to a lactone-bearing fragment. PMID:11674687

  12. Simplified Fabrication of Helical Copper Antennas

    NASA Technical Reports Server (NTRS)

    Petro, Andrew

    2006-01-01

    A simplified technique has been devised for fabricating helical antennas for use in experiments on radio-frequency generation and acceleration of plasmas. These antennas are typically made of copper (for electrical conductivity) and must have a specific helical shape and precise diameter.

  13. Simplifying Data. USMES Beginning "How To" Set.

    ERIC Educational Resources Information Center

    Agro, Sally; And Others

    In this set of three booklets on simplifying data, primary grade students learn how to round off data and to find the median and average from sets of data. The major emphasis in all Unified Sciences and Mathematics for Elementary Schools (USMES) units is on open-ended, long-range investigations of real problems. In most instances students learn…

  14. Simplifying Data. USMES Intermediate "How To" Set.

    ERIC Educational Resources Information Center

    Agro, Sally; And Others

    In this set of six booklets on simplifying data, intermediate grade students learn how to tell what data show, find the median/mean/mode from sets of data, find different kinds of ranges, and use key numbers to compare two sets of data. The major emphasis in all Unified Sciences and Mathematics for Elementary Schools (USMES) units is on…

  15. Gaining Algorithmic Insight through Simplifying Constraints.

    ERIC Educational Resources Information Center

    Ginat, David

    2002-01-01

    Discusses algorithmic problem solving in computer science education, particularly algorithmic insight, and focuses on the relevance and effectiveness of the heuristic simplifying constraints which involves simplification of a given problem to a problem in which constraints are imposed on the input data. Presents three examples involving…

  16. Simplified modeling for infiltration and radon entry

    SciTech Connect

    Sherman, M.H.

    1992-08-01

    Air leakage in the envelopes of residential buildings is the primary mechanism for provided ventilation to those buildings. For radon the same mechanisms that drive the ventilation, drive the radon entry This paper attempts to provide a simplified physical model that can be used to understand the interactions between the building leakage distribution, the forces that drive infiltration and ventilation, and indoor radon concentrations, Combining both ventilation and entry modeling together allows an estimation of Radon concentration and exposure to be made and demonstrates how changes in the envelope or ventilation system would affect it. This paper will develop simplified modeling approaches for estimating both ventilation rate and radon entry rate based on the air tightness of the envelope and the driving forces. These approaches will use conventional leakage values (i.e. effective leakage area ) to quantify the air tightness and include natural and mechanical driving forces. This paper will introduce a simplified parameter, the Radon Leakage Area, that quantifies the resistance to radon entry. To be practical for dwellings, modeling of the occupant exposures to indoor pollutants must be simple to use and not require unreasonable input data. This paper presents the derivation of the simplified physical model, and applies that model to representative situations to explore the tendencies to be expected under different circumstances.

  17. Simplified Tutorial Programming for Interactive CAI.

    ERIC Educational Resources Information Center

    Jelden, D. L.

    A validated instructional model generated on a large mainframe computer by the military was modified to a microcomputer format for use in programming tutorial computer assisted instruction (CAI) materials, and a simplified, compatible system of generating programs was identified--CP/M and MP/M from Digital Research Corporation. In order to…

  18. Simplified procedures for designing composite bolted joints

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C.

    1988-01-01

    Simplified procedures are described to design and analyze single and multi-bolt composite joints. Numerical examples illustrate the use of these methods. Factors affecting composite bolted joints are summarized. References are cited where more detailed discussion is presented on specific aspects of composite bolted joints. Design variables associated with these joints are summarized in the appendix.

  19. Simplified Recipes for Day Care Centers.

    ERIC Educational Resources Information Center

    Asmussen, Patricia D.

    The spiral-bound collection of 156 simplified recipes is designed to help those who prepare food for groups of children at day care centers. The recipes provide for 25 child-size servings to meet the nutritional needs and appetites of children from 2 to 6 years of age. The first section gives general information on ladle and scoop sizes, weights…

  20. Simplified Aid For Crew Rescue (SAFR)

    NASA Technical Reports Server (NTRS)

    Fisher, H. Thomas

    1990-01-01

    Viewgraphs and discussion of a Crew Emergency Rescue System (CERS) are presented. Topics covered include: functional description; operational description; interfaces with other subsystems/elements; simplified aid for crew rescue (SACR) characteristics; potential resource requirements; logistics, repair, and resupply; potential performance improvements; and automation impact.

  1. DUBLIN CORE

    EPA Science Inventory

    The Dublin Core is a metadata element set intended to facilitate discovery of electronic resources. It was originally conceived for author-generated descriptions of Web resources, and the Dublin Core has attracted broad ranging international and interdisciplinary support. The cha...

  2. Simplified models of mixed dark matter

    SciTech Connect

    Cheung, Clifford; Sanford, David E-mail: dsanford@caltech.edu

    2014-02-01

    We explore simplified models of mixed dark matter (DM), defined here to be a stable relic composed of a singlet and an electroweak charged state. Our setup describes a broad spectrum of thermal DM candidates that can naturally accommodate the observed DM abundance but are subject to substantial constraints from current and upcoming direct detection experiments. We identify ''blind spots'' at which the DM-Higgs coupling is identically zero, thus nullifying direct detection constraints on spin independent scattering. Furthermore, we characterize the fine-tuning in mixing angles, i.e. well-tempering, required for thermal freeze-out to accommodate the observed abundance. Present and projected limits from LUX and XENON1T force many thermal relic models into blind spot tuning, well-tempering, or both. This simplified model framework generalizes bino-Higgsino DM in the MSSM, singlino-Higgsino DM in the NMSSM, and scalar DM candidates that appear in models of extended Higgs sectors.

  3. Development of a simplified biofilm model

    NASA Astrophysics Data System (ADS)

    Sarkar, Sushovan; Mazumder, Debabrata

    2015-11-01

    A simplified approach for analyzing the biofilm process in deriving an easy model has been presented. This simplified biofilm model formulated correlations between substrate concentration in the influent/effluent and at biofilm-liquid interface along with substrate flux and biofilm thickness. The model essentially considered the external mass transport according to Fick's Law, steady state substrate as well as biomass balance for attached growth microorganisms. In substrate utilization, Monod growth kinetics has been followed incorporating relevant boundary conditions at the liquid-biofilm interface and at the attachment surface. The numerical solution of equations was accomplished using Runge-Kutta method and accordingly an integrated computer program was developed. The model has been successfully applied in a distinct set of trials with varying range of representative input variables. The model performance was compared with available existing methods and it was found an easy, accurate method that can be used for process design of biofilm reactor.

  4. Simplified Analytical Model of a Six-Degree-of-Freedom Large-Gap Magnetic Suspension System

    NASA Technical Reports Server (NTRS)

    Groom, Nelson J.

    1997-01-01

    A simplified analytical model of a six-degree-of-freedom large-gap magnetic suspension system is presented. The suspended element is a cylindrical permanent magnet that is magnetized in a direction which is perpendicular to its axis of symmetry. The actuators are air core electromagnets mounted in a planar array. The analytical model consists of an open-loop representation of the magnetic suspension system with electromagnet currents as inputs.

  5. Phase III Simplified Integrated Test (SIT) results - Space Station ECLSS testing

    NASA Technical Reports Server (NTRS)

    Roberts, Barry C.; Carrasquillo, Robyn L.; Dubiel, Melissa Y.; Ogle, Kathryn Y.; Perry, Jay L.; Whitley, Ken M.

    1990-01-01

    During 1989, phase III testing of Space Station Freedom Environmental Control and Life Support Systems (ECLSS) began at Marshall Space Flight Center (MSFC) with the Simplified Integrated Test. This test, conducted at the MSFC Core Module Integration Facility (CMIF), was the first time the four baseline air revitalization subsystems were integrated together. This paper details the results and lessons learned from the phase III SIT. Future plans for testing at the MSFC CMIF are also discussed.

  6. Simplified Linear Multivariable Control Of Robots

    NASA Technical Reports Server (NTRS)

    Seraji, Homayoun

    1989-01-01

    Simplified method developed to design control system that makes joints of robot follow reference trajectories. Generic design includes independent multivariable feedforward and feedback controllers. Feedforward controller based on inverse of linearized model of dynamics of robot and implements control law that contains only proportional and first and second derivatives of reference trajectories with respect to time. Feedback controller, which implements control law of proportional, first-derivative, and integral terms, makes tracking errors converge toward zero as time passes.

  7. Simplified dichromated gelatin hologram recording process

    NASA Technical Reports Server (NTRS)

    Georgekutty, Tharayil G.; Liu, Hua-Kuang

    1987-01-01

    A simplified method for making dichromated gelatin (DCG) holographic optical elements (HOE) has been discovered. The method is much less tedious and it requires a period of processing time comparable with that for processing a silver halide hologram. HOE characteristics including diffraction efficiency (DE), linearity, and spectral sensitivity have been quantitatively investigated. The quality of the holographic grating is very high. Ninety percent or higher diffraction efficiency has been achieved in simple plane gratings made by this process.

  8. A simplified solar cell array modelling program

    NASA Technical Reports Server (NTRS)

    Hughes, R. D.

    1982-01-01

    As part of the energy conversion/self sufficiency efforts of DSN engineering, it was necessary to have a simplified computer model of a solar photovoltaic (PV) system. This article describes the analysis and simplifications employed in the development of a PV cell array computer model. The analysis of the incident solar radiation, steady state cell temperature and the current-voltage characteristics of a cell array are discussed. A sample cell array was modelled and the results are presented.

  9. Simplified robot arm dynamics for control

    NASA Technical Reports Server (NTRS)

    Bejczy, A. K.; Paul, R. P.

    1981-01-01

    A brief summary and evaluation is presented on the use of symbolic state equation techniques in order to represent robot arm dynamics with sufficient accuracy for controlling arm motion. The use of homogeneous transformations and the Lagrangian formulation of mechanics offers a convenient frame for the derivation, analysis and simplification of complex robot dynamics equations. It is pointed out that simplified state equations can represent robot arm dynamics with good accuracy.

  10. 24. A CORE WORKER DISPLAYS THE CORE BOX AND CORES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. A CORE WORKER DISPLAYS THE CORE BOX AND CORES FOR A BRASS GATE VALVE BODY MADE ON A CORE BOX, CA. 1950. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  11. Simplified tools for evaluating domestic ventilation systems

    SciTech Connect

    Maansson, L.G.; Orme, M.

    1999-07-01

    Within an International Energy Agency (IEA) project, Annex 27, experts from 8 countries (Canada, France, Italy, Japan, The Netherlands, Sweden, UK and USA) have developed simplified tools for evaluating domestic ventilation systems during the heating season. Tools for building and user aspects, thermal comfort, noise, energy, life cycle cost, reliability and indoor air quality (IAQ) have been devised. The results can be used both for dwellings at the design stage and after construction. The tools lead to immediate answers and indications about the consequences of different choices that may arise during discussion with clients. This paper presents an introduction to these tools. Examples applications of the indoor air quality and energy simplified tools are also provided. The IAQ tool accounts for constant emission sources, CO{sub 2}, cooking products, tobacco smoke, condensation risks, humidity levels (i.e., for judging the risk for mould and house dust mites), and pressure difference (for identifying the risk for radon or land fill spillage entering the dwelling or problems with indoor combustion appliances). An elaborated set of design parameters were worked out that resulted in about 17,000 combinations. By using multi-variate analysis it was possible to reduce this to 174 combinations for IAQ. In addition, a sensitivity analysis was made using 990 combinations. The results from all the runs were used to develop a simplified tool, as well as quantifying equations relying on the design parameters. A computerized energy tool has also been developed within this project, which takes into account air tightness, climate, window airing pattern, outdoor air flow rate and heat exchange efficiency.

  12. Simplified Explosive Joining of Tubes to Fittings

    NASA Technical Reports Server (NTRS)

    Bement, L. J.; Bailey, J. W.; Perry, R.; Finch, M. S.

    1987-01-01

    Technique simplifies tube-to-fitting joining, as compared to fusion welding, and provides improvement on standard procedures used to join tubes explosively to tube fittings. Special tool inserted into tube to be joined. Tool allows strip of ribbon explosive to be placed right at joint. Ribbon explosive and mild detonating fuse allows use of smaller charge. Assembled tool storable, and process amenable to automation. Assembly of components, insertion of tool into weld site, and joining operation mechanized without human contact. Used to assemble components in nuclear reactors or in other environments hostile to humans.

  13. Simplified stock markets described by number operators

    NASA Astrophysics Data System (ADS)

    Bagarello, F.

    2009-06-01

    In this paper we continue our systematic analysis of the operatorial approach previously proposed in an economical context and we discuss a mixed toy model of a simplified stock market, i.e. a model in which the price of the shares is given as an input. We deduce the time evolution of the portfolio of the various traders of the market, as well as of other observable quantities. As in a previous paper, we solve the equations of motion by means of a fixed point like approximation.

  14. Simplified dynamic buckling assessment of steel containments

    SciTech Connect

    Farrar, C.R.; Duffey, T.A.; Renick, D.H.

    1993-02-01

    A simplified, three-degree-of-freedom analytical procedure for performing a response spectrum buckling analysis of a thin containment shell is developed. Two numerical examples with R/t values which bound many existing steel containments are used to illustrate the procedure. The role of damping on incipient buckling acceleration level is evaluated for a regulatory seismic spectrum using the two numerical examples. The zero-period acceleration level that causes incipient buckling in either of the two containments increases 31% when damping is increased from 1% to 4% of critical. Comparisons with finite element results on incipient buckling levels are favorable.

  15. Chronic Meningitis: Simplifying a Diagnostic Challenge.

    PubMed

    Baldwin, Kelly; Whiting, Chris

    2016-03-01

    Chronic meningitis can be a diagnostic dilemma for even the most experienced clinician. Many times, the differential diagnosis is broad and encompasses autoimmune, neoplastic, and infectious etiologies. This review will focus on a general approach to chronic meningitis to simplify the diagnostic challenges many clinicians face. The article will also review the most common etiologies of chronic meningitis in some detail including clinical presentation, diagnostic testing, treatment, and outcomes. By using a case-based approach, we will focus on the key elements of clinical presentation and laboratory analysis that will yield the most rapid and accurate diagnosis in these complicated cases. PMID:26888190

  16. Core strengthening.

    PubMed

    Arendt, Elizabeth A

    2007-01-01

    Several recent studies have evaluated interventional techniques designed to reduce the risk of serious knee injuries, particularly noncontact anterior cruciate ligament injuries in female athletes. Maintenance of rotational control of the limb underneath the pelvis, especially in response to cutting and jumping activities, is a common goal in many training programs. Rotational control of the limb underneath the pelvis is mediated by a complex set of factors including the strength of the trunk muscles and the relationship between the core muscles. It is important to examine the interrelationship between lower extremity function and core stability. PMID:17472321

  17. Simplified Simulation of Mass Transfer in Double White Dwarf Systems

    NASA Astrophysics Data System (ADS)

    Vannah, Sara; Frank, Juhan

    2016-01-01

    The behavior both stable and unstable mass transfer in semi-detached double white dwarfs triggers a cornucopia of astrophysical phenomena including Type Ia supernovae and AM CVn stars. Current 3D hydrodynamic simulations of the evolution these systems following the mass transfer, binary orbital parameters, and the self-consistent gravitational field over several tens of orbital periods have produced a wealth of data. However, these simulations can take weeks to months in high-performance computing platforms to execute. To help with the interpretation of results of such large scale simulations, and to enable a quick exploration of binary parameter space, we have developed a Mathematica code that integrates forward in time a system of 5 ODEs describing the orbit-averaged evolution of the binary separation as well as the radius, mass, and spin angular momentum of both components of the binary. By adjusting a few parameters describing the mass transfer as a function of the Roche-lobe overflow and the strength of the tidal coupling between the orbit and component spins we are able to obtain approximate fits to previously run hydrodynamic simulations. This simplified simulation is able to run simulations similar to the hydrodynamic versions in a matter of seconds on a dual-core PC or Mac computer.

  18. Simplifying the circuit of Josephson parametric converters

    NASA Astrophysics Data System (ADS)

    Abdo, Baleegh; Brink, Markus; Chavez-Garcia, Jose; Keefe, George

    Josephson parametric converters (JPCs) are quantum-limited three-wave mixing devices that can play various important roles in quantum information processing in the microwave domain, including amplification of quantum signals, transduction of quantum information, remote entanglement of qubits, nonreciprocal amplification, and circulation of signals. However, the input-output and biasing circuit of a state-of-the-art JPC consists of bulky components, i.e. two commercial off-chip broadband 180-degree hybrids, four phase-matched short coax cables, and one superconducting magnetic coil. Such bulky hardware significantly hinders the integration of JPCs in scalable quantum computing architectures. In my talk, I will present ideas on how to simplify the JPC circuit and show preliminary experimental results

  19. Combustion Safety Simplified Test Protocol Field Study

    SciTech Connect

    Brand, L.; Cautley, D.; Bohac, D.; Francisco, P.; Shen, L.; Gloss, S.

    2015-11-01

    Combustions safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives. A survey of state weatherization agencies on combustion safety issues, details of a field data collection instrumentation package, summary of data collected over seven months, data analysis and results are included. The project team collected field data on 11 houses in 2015.

  20. Thermodynamic behaviour of simplified geothermal reservoirs

    SciTech Connect

    Hiriart, G.; Sanchez, E.

    1985-01-22

    Starting from the basic laws of conservation of mass and energy, the differential equations that represent the thermodynamic behavior of a simplified geothermal reservoir are derived. Its application is limited to a reservoir of high permeability as it usually occurs in the central zone of a geothermal field. A very practical method to solve numerically the equations is presented, based on the direct use of the steam tables. The method, based in one general equation, is extended and illustrated with a numerical example to the case of segregated mass extraction, variable influx and heat exchange between rock and fluid. As it is explained, the method can be easily coupled to several influx models already developed somewhere else. The proposed model can become an important tool to solve practical problems, where like in Los Azufres Mexico, the geothermal field can be divided in an inner part where flashing occurs and an exterior field where storage of water plays the main role.

  1. Aeroacoustic Analysis of a Simplified Landing Gear

    NASA Technical Reports Server (NTRS)

    Lockard, David P.; Khorrami, Mehdi, R.; Li, Fei

    2004-01-01

    A hybrid approach is used to investigate the noise generated by a simplified landing gear without small scale parts such as hydraulic lines and fasteners. The Ffowcs Williams and Hawkings equation is used to predict the noise at far-field observer locations from flow data provided by an unsteady computational fluid dynamics calculation. A simulation with 13 million grid points has been completed, and comparisons are made between calculations with different turbulence models. Results indicate that the turbulence model has a profound effect on the levels and character of the unsteadiness. Flow data on solid surfaces and a set of permeable surfaces surrounding the gear have been collected. Noise predictions using the porous surfaces appear to be contaminated by errors caused by large wake fluctuations passing through the surfaces. However, comparisons between predictions using the solid surfaces with the near-field CFD solution are in good agreement giving confidence in the far-field results.

  2. Simplified Model of Nonlinear Landau Damping

    SciTech Connect

    N. A. Yampolsky and N. J. Fisch

    2009-07-16

    The nonlinear interaction of a plasma wave with resonant electrons results in a plateau in the electron distribution function close to the phase velocity of the plasma wave. As a result, Landau damping of the plasma wave vanishes and the resonant frequency of the plasma wave downshifts. However, this simple picture is invalid when the external driving force changes the plasma wave fast enough so that the plateau cannot be fully developed. A new model to describe amplification of the plasma wave including the saturation of Landau damping and the nonlinear frequency shift is proposed. The proposed model takes into account the change of the plasma wave amplitude and describes saturation of the Landau damping rate in terms of a single fluid equation, which simplifies the description of the inherently kinetic nature of Landau damping. A proposed fluid model, incorporating these simplifications, is verified numerically using a kinetic Vlasov code.

  3. Space station ECLSS simplified integrated test

    NASA Technical Reports Server (NTRS)

    Schunk, Richard G.; Bagdigian, Robert M.; Carrasquillo, Robyn L.; Ogle, Kathyrn Y.; Wieland, Paul O.

    1989-01-01

    A discussion of the Space Station Simplified Integrated Test (SIT) was conducted. The first in a series of three integrated Environmental Control and Life Support (ECLS) system tests, the primary objectives of the SIT were to verify proper operation of ECLS subsystems functioning in an integrated fashion as well as to gather preliminary performance data for the partial ECLS system used in the test. A description of the SIT configuration, a summary of events, a discussion of anomalies that occurred during the test, and detailed results and analysis from individual measurements and water and gas samples taken during the test are included. The preprototype ECLS hardware used in the test is reported providing an overall process description and theory of operation for each hardware item.

  4. Simplifying cardiovascular magnetic resonance pulse sequence terminology.

    PubMed

    Friedrich, Matthias G; Bucciarelli-Ducci, Chiara; White, James A; Plein, Sven; Moon, James C; Almeida, Ana G; Kramer, Christopher M; Neubauer, Stefan; Pennell, Dudley J; Petersen, Steffen E; Kwong, Raymond Y; Ferrari, Victor A; Schulz-Menger, Jeanette; Sakuma, Hajime; Schelbert, Erik B; Larose, Éric; Eitel, Ingo; Carbone, Iacopo; Taylor, Andrew J; Young, Alistair; de Roos, Albert; Nagel, Eike

    2014-01-01

    We propose a set of simplified terms to describe applied Cardiovascular Magnetic Resonance (CMR) pulse sequence techniques in clinical reports, scientific articles and societal guidelines or recommendations. Rather than using various technical details in clinical reports, the description of the technical approach should be based on the purpose of the pulse sequence. In scientific papers or other technical work, this should be followed by a more detailed description of the pulse sequence and settings. The use of a unified set of widely understood terms would facilitate the communication between referring physicians and CMR readers by increasing the clarity of CMR reports and thus improve overall patient care. Applied in research articles, its use would facilitate non-expert readers' understanding of the methodology used and its clinical meaning. PMID:25551695

  5. Simplified fundamental force and mass measurements

    NASA Astrophysics Data System (ADS)

    Robinson, I. A.

    2016-08-01

    The watt balance relates force or mass to the Planck constant h, the metre and the second. It enables the forthcoming redefinition of the unit of mass within the SI by measuring the Planck constant in terms of mass, length and time with an uncertainty of better than 2 parts in 108. To achieve this, existing watt balances require complex and time-consuming alignment adjustments limiting their use to a few national metrology laboratories. This paper describes a simplified construction and operating principle for a watt balance which eliminates the need for the majority of these adjustments and is readily scalable using either electromagnetic or electrostatic actuators. It is hoped that this will encourage the more widespread use of the technique for a wide range of measurements of force or mass. For example: thrust measurements for space applications which would require only measurements of electrical quantities and velocity/displacement.

  6. Structure and strategy in encoding simplified graphs

    NASA Technical Reports Server (NTRS)

    Schiano, Diane J.; Tversky, Barbara

    1992-01-01

    Tversky and Schiano (1989) found a systematic bias toward the 45-deg line in memory for the slopes of identical lines when embedded in graphs, but not in maps, suggesting the use of a cognitive reference frame specifically for encoding meaningful graphs. The present experiments explore this issue further using the linear configurations alone as stimuli. Experiments 1 and 2 demonstrate that perception and immediate memory for the slope of a test line within orthogonal 'axes' are predictable from purely structural considerations. In Experiments 3 and 4, subjects were instructed to use a diagonal-reference strategy in viewing the stimuli, which were described as 'graphs' only in Experiment 3. Results for both studies showed the diagonal bias previously found only for graphs. This pattern provides converging evidence for the diagonal as a cognitive reference frame in encoding linear graphs, and demonstrates that even in highly simplified displays, strategic factors can produce encoding biases not predictable solely from stimulus structure alone.

  7. Entropy reduction via simplified image contourization

    NASA Technical Reports Server (NTRS)

    Turner, Martin J.

    1993-01-01

    The process of contourization is presented which converts a raster image into a set of plateaux or contours. These contours can be grouped into a hierarchical structure, defining total spatial inclusion, called a contour tree. A contour coder has been developed which fully describes these contours in a compact and efficient manner and is the basis for an image compression method. Simplification of the contour tree has been undertaken by merging contour tree nodes thus lowering the contour tree's entropy. This can be exploited by the contour coder to increase the image compression ratio. By applying general and simple rules derived from physiological experiments on the human vision system, lossy image compression can be achieved which minimizes noticeable artifacts in the simplified image.

  8. Miniaturized photoelectric angular sensor with simplified design

    NASA Astrophysics Data System (ADS)

    Dumbravescu, Niculae; Schiaua, Silviu

    1999-09-01

    In building the movable elements of robots, peripheral devices and measuring apparata, increasing the resolution of the angular sensor systems, based on incremental rotary encoders, is essential, together with decreasing the complexity, dimensions and weight. Especially when the angular sensor is integrated in a measuring system, belonging to a programmed light airplane for surveillance, the key issue is to reduce both dimensions and weight. This can be done using a simplified design, which consists in the following solutions: replacement of the fragile Cr on glass substrate, 1.5 mm thick (normally used for the fabrication of incremental disks), with light Cr on polycarbonate substrate, with only 0.15 mm thick; the absence of collimating optics (based on microlenses, used in IR emitter-photocell receiver assembly), as a result of the good coupling efficiency (due to the possible approaching of these elements at minimum 0.45 mm); the shrinkage of the disk's diameters to only 14 mm; the use of surface mounting devices and the related surface mounting technology, enabling to reduce dimensions and weight. The maximum number of slits on a 14 mm diameter dividing disk, usually obtained in a Cr on polycarbonate version, being approx. 1000, no problem occurs in our case, for 360 slits. The requested angular resolution (only 0.5 degrees for the light airplane), using the whole classical '4x digital multiplication' is not necessary, but a lower one of only 2x, resulting in a simplified electronics. The proposed design permitted, that an original arrangement, for building a small size, lightweight, heavy-duty incremental transducer based angular sensor system, to be obtained, useful not only in avionics, but also in robotics, or other special applications. Besides, extending the number of fixed gratings (masks) allows, that many primary signals to be derived, and a further increase in resolution of even 6 angular minutes to be obtained from the initial 360 slits.

  9. Simplified Modeling of Oxidation of Hydrocarbons

    NASA Technical Reports Server (NTRS)

    Bellan, Josette; Harstad, Kenneth

    2008-01-01

    A method of simplified computational modeling of oxidation of hydrocarbons is undergoing development. This is one of several developments needed to enable accurate computational simulation of turbulent, chemically reacting flows. At present, accurate computational simulation of such flows is difficult or impossible in most cases because (1) the numbers of grid points needed for adequate spatial resolution of turbulent flows in realistically complex geometries are beyond the capabilities of typical supercomputers now in use and (2) the combustion of typical hydrocarbons proceeds through decomposition into hundreds of molecular species interacting through thousands of reactions. Hence, the combination of detailed reaction- rate models with the fundamental flow equations yields flow models that are computationally prohibitive. Hence, further, a reduction of at least an order of magnitude in the dimension of reaction kinetics is one of the prerequisites for feasibility of computational simulation of turbulent, chemically reacting flows. In the present method of simplified modeling, all molecular species involved in the oxidation of hydrocarbons are classified as either light or heavy; heavy molecules are those having 3 or more carbon atoms. The light molecules are not subject to meaningful decomposition, and the heavy molecules are considered to decompose into only 13 specified constituent radicals, a few of which are listed in the table. One constructs a reduced-order model, suitable for use in estimating the release of heat and the evolution of temperature in combustion, from a base comprising the 13 constituent radicals plus a total of 26 other species that include the light molecules and related light free radicals. Then rather than following all possible species through their reaction coordinates, one follows only the reduced set of reaction coordinates of the base. The behavior of the base was examined in test computational simulations of the combustion of

  10. New weak keys in simplified IDEA

    NASA Astrophysics Data System (ADS)

    Hafman, Sari Agustini; Muhafidzah, Arini

    2016-02-01

    Simplified IDEA (S-IDEA) is simplified version of International Data Encryption Algorithm (IDEA) and useful teaching tool to help students to understand IDEA. In 2012, Muryanto and Hafman have found a weak key class in the S-IDEA by used differential characteristics in one-round (0, ν, 0, ν) → (0,0, ν, ν) on the first round to produce input difference (0,0, ν, ν) on the fifth round. Because Muryanto and Hafman only use three differential characteristics in one-round, we conducted a research to find new differential characteristics in one-round and used it to produce new weak key classes of S-IDEA. To find new differential characteristics in one-round of S-IDEA, we applied a multiplication mod 216+1 on input difference and combination of active sub key Z1, Z4, Z5, Z6. New classes of weak keys are obtained by combining all of these characteristics and use them to construct two new differential characteristics in full-round of S-IDEA with or without the 4th round sub key. In this research, we found six new differential characteristics in one round and combined them to construct two new differential characteristics in full-round of S-IDEA. When two new differential characteristics in full-round of S-IDEA are used and the 4th round sub key required, we obtain 2 new classes of weak keys, 213 and 28. When two new differential characteristics in full-round of S-IDEA are used, yet the 4th round sub key is not required, the weak key class of 213 will be 221 and 28 will be 210. Membership test can not be applied to recover the key bits in those weak key classes. The recovery of those unknown key bits can only be done by using brute force attack. The simulation result indicates that the bit of the key can be recovered by the longest computation time of 0,031 ms.

  11. Simplified tube models for entangled supramolecular polymers

    NASA Astrophysics Data System (ADS)

    Boudara, Victor; Read, Daniel

    2015-03-01

    This presentation describes current efforts investigating non-linear rheology of entangled, supramolecular polymeric materials. We describe two recently developed models: 1) We have developed a simplified model for the rheology of entangled telechelic star polymers. This is based on a pre-averaged orientation tensor, a stretch equation, and stretch-dependant probability of detachment of the sticker. In both linear and non-linear regimes, we produce maps of the whole parameter space, indicating the parameter values for which qualitative changes in response to flow are predicted. Results in the linear rheology regime are consistent with previous more detailed models and are in qualitative agreement with experimental data. 2) Using the same modelling framework, we investigate entangled linear polymers with stickers along the backbone. We use a set of coupled equations to describe the stretch between each stickers, and use equations similar to our star model for attachment/detachment of the sticky groups. This model is applicable to industrial polymers such as entangled thermoplastic elasomers, or functionalised model linear polymers. The work leading to these results has received funding from the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme (FP7/2007-2013) under REA Grant Agreement No. 607937 (SUPOLEN).

  12. Combustion Safety Simplified Test Protocol Field Study

    SciTech Connect

    Brand, L; Cautley, D.; Bohac, D.; Francisco, P.; Shen, L.; Gloss, S.

    2015-11-05

    "9Combustions safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives. A survey of state weatherization agencies on combustion safety issues, details of a field data collection instrumentation package, summary of data collected over seven months, data analysis and results are included. The project provides several key results. State weatherization agencies do not generally track combustion safety failures, the data from those that do suggest that there is little actual evidence that combustion safety failures due to spillage from non-dryer exhaust are common and that only a very small number of homes are subject to the failures. The project team collected field data on 11 houses in 2015. Of these homes, two houses that demonstrated prolonged and excessive spillage were also the only two with venting systems out of compliance with the National Fuel Gas Code. The remaining homes experienced spillage that only occasionally extended beyond the first minute of operation. Combustion zone depressurization, outdoor temperature, and operation of individual fans all provide statistically significant predictors of spillage.

  13. Simplified Models for Dark Matter Model Building

    NASA Astrophysics Data System (ADS)

    DiFranzo, Anthony Paul

    The largest mass component of the universe is a longstanding mystery to the physics community. As a glaring source of new physics beyond the Standard Model, there is a large effort to uncover the quantum nature of dark matter. Many probes have been formed to search for this elusive matter; cultivating a rich environment for a phenomenologist. In addition to the primary probes---colliders, direct detection, and indirect detection---each with their own complexities, there is a plethora of prospects to illuminate our unanswered questions. In this work, phenomenological techniques for studying dark matter and other possible hints of new physics will be discussed. This work primarily focuses on the use of Simplified Models, which are intended to be a compromise between generality and validity of the theoretical description. They are often used to parameterize a particular search, develop a well-defined sense of complementarity between searches, or motivate new search strategies. Explicit examples of such models and how they may be used will be the highlight of each chapter.

  14. Design for a simplified cochlear implant system.

    PubMed

    An, Soon Kwan; Park, Se-Ik; Jun, Sang Beom; Lee, Choong Jae; Byun, Kyung Min; Sung, Jung Hyun; Wilson, Blake S; Rebscher, Stephen J; Oh, Seung Ha; Kim, Sung June

    2007-06-01

    A simplified cochlear implant (CI) system would be appropriate for widespread use in developing countries. Here, we describe a CI that we have designed to realize such a concept. The system implements 8 channels of processing and stimulation using the continuous interleaved sampling (CIS) strategy. A generic digital signal processing (DSP) chip is used for the processing, and the filtering functions are performed with a fast Fourier transform (FFT) of a microphone or other input. Data derived from the processing are transmitted through an inductive link using pulse width modulation (PWM) encoding and amplitude shift keying (ASK) modulation. The same link is used in the reverse direction for backward telemetry of electrode and system information. A custom receiver-stimulator chip has been developed that demodulates incoming data using pulse counting and produces charge balanced biphasic pulses at 1000 pulses/s/electrode. This chip is encased in a titanium package that is hermetically sealed using a simple but effective method. A low cost metal-silicon hybrid mold has been developed for fabricating an intracochlear electrode array with 16 ball-shaped stimulating contacts. PMID:17554817

  15. Simplified environmental study on innovative bridge structure.

    PubMed

    Bouhaya, Lina; Le Roy, Robert; Feraille-Fresnet, Adélaïde

    2009-03-15

    The aim of this paper is to present a simplified life cycle assessment on an innovative bridge structure, made of wood and ultra high performance concrete, which combines mechanical performance with minimum environmental impact. The environmental analysis was conducted from cradle to grave using the Life Cycle Assessment method. It was restricted to energy release and greenhouse gas emissions. Assumptions are detailed for each step of the analysis. For the wood end-of-life, three scenarios were proposed: dumping, burning, and recycling. Results show that the most energy needed is in the production phase, which represents 73.4% of the total amount. Analysis shows that the renewable energy is about 70% of the production energy. Wood, through its biomass CO2, contributes positively to the environmental impact. It was concluded that no scenario can be the winner on both impacts. Indeed, the end-of-life wood recycling gives the best impact on CO2 release, whereas burning wood, despite its remarkable energy impact is the worst. According to the emphasis given to each impact, designers will be able to choose one or the other. PMID:19368215

  16. Simplified Optics and Controls for Laser Communications

    NASA Technical Reports Server (NTRS)

    Chen, Chien-Chung; Hemmati, Hamid

    2006-01-01

    A document discusses an architecture of a spaceborne laser communication system that provides for a simplified control subsystem that stabilizes the line of sight in a desired direction. Heretofore, a typical design for a spaceborne laser communication system has called for a high-bandwidth control loop, a steering mirror and associated optics, and a fast steering-mirror actuator to stabilize the line of sight in the presence of vibrations. In the present architecture, the need for this fast steering-mirror subsystem is eliminated by mounting the laser-communication optics on a disturbance-free platform (DFP) that suppresses coupling of vibrations to the optics by 60 dB. Taking advantage of microgravitation, in the DFP, the optical assembly is free-flying relative to the rest of the spacecraft, and a low-spring-constant pointing control subsystem exerts small forces to regulate the position and orientation of the optics via voice coils. All steering is effected via the DFP, which can be controlled in all six degrees of freedom relative to the spacecraft. A second control loop, closed around a position sensor and the spacecraft attitude-control system, moves the spacecraft as needed to prevent mechanical contact with the optical assembly.

  17. Interferometric phase reconstruction using simplified coherence network

    NASA Astrophysics Data System (ADS)

    Zhang, Kui; Song, Ruiqing; Wang, Hui; Wu, Di; Wang, Hua

    2016-09-01

    Interferometric time-series analysis techniques, which extend the traditional differential radar interferometry, have demonstrated a strong capability for monitoring ground surface displacement. Such techniques are able to obtain the temporal evolution of ground deformation within millimeter accuracy by using a stack of synthetic aperture radar (SAR) images. In order to minimize decorrelation between stacked SAR images, the phase reconstruction technique has been developed recently. The main idea of this technique is to reform phase observations along a SAR stack by taking advantage of a maximum likelihood estimator which is defined on the coherence matrix estimated from each target. However, the phase value of a coherence matrix element might be considerably biased when its corresponding coherence is low. In this case, it will turn to an outlying sample affecting the corresponding phase reconstruction process. In order to avoid this problem, a new approach is developed in this paper. This approach considers a coherence matrix element to be an arc in a network. A so-called simplified coherence network (SCN) is constructed to decrease the negative impact of outlying samples. Moreover, a pointed iterative strategy is designed to resolve the transformed phase reconstruction problem defined on a SCN. For validation purposes, the proposed method is applied to 29 real SAR images. The results demonstrate that the proposed method has an excellent computational efficiency and could obtain more reliable phase reconstruction solutions compared to the traditional method using phase triangulation algorithm.

  18. Simplified liquid oxygen propellant conditioning concepts

    NASA Technical Reports Server (NTRS)

    Cleary, N. L.; Holt, K. A.; Flachbart, R. H.

    1995-01-01

    Current liquid oxygen feed systems waste propellant and use hardware, unnecessary during flight, to condition the propellant at the engine turbopumps prior to launch. Simplified liquid oxygen propellant conditioning concepts are being sought for future launch vehicles. During a joint program, four alternative propellant conditioning options were studied: (1) passive recirculation; (2) low bleed through the engine; (3) recirculation lines; and (4) helium bubbling. The test configuration for this program was based on a vehicle design which used a main recirculation loop that was insulated on the downcomer and uninsulated on the upcomer. This produces a natural convection recirculation flow. The test article for this program simulated a feedline which ran from the main recirculation loop to the turbopump. The objective was to measure the temperature profile of this test article. Several parameters were varied from the baseline case to determine their effects on the temperature profile. These parameters included: flow configuration, feedline slope, heat flux, main recirculation loop velocity, pressure, bleed rate, helium bubbling, and recirculation lines. The heat flux, bleed rate, and recirculation configurations produced the greatest changes from the baseline temperature profile. However, the temperatures in the feedline remained subcooled. Any of the options studied could be used in future vehicles.

  19. Simplified methods for calculating photodissociation rates

    NASA Technical Reports Server (NTRS)

    Shimazaki, T.; Ogawa, T.; Farrell, B. C.

    1977-01-01

    Simplified methods for calculating the transmission of solar UV radiation and the dissociation coefficients of various molecules are compared. A significant difference sometimes appears in calculations of the individual band, but the total transmission and the total dissociation coefficients integrated over the entire SR (solar radiation) band region agree well between the methods. The ambiguities in the solar flux data affect the calculated dissociation coefficients more strongly than does the method. A simpler method is developed for the purpose of reducing the computation time and computer memory size necessary for storing coefficients of the equations. The new method can reduce the computation time by a factor of more than 3 and the memory size by a factor of more than 50 compared with the Hudson-Mahle method, and yet the result agrees within 10 percent (in most cases much less) with the original Hudson-Mahle results, except for H2O and CO2. A revised method is necessary for these two molecules, whose absorption cross sections change very rapidly over the SR band spectral range.

  20. Simplified Dynamic Analysis of Grinders Spindle Node

    NASA Astrophysics Data System (ADS)

    Demec, Peter

    2014-12-01

    The contribution deals with the simplified dynamic analysis of surface grinding machine spindle node. Dynamic analysis is based on the use of the transfer matrix method, which is essentially a matrix form of method of initial parameters. The advantage of the described method, despite the seemingly complex mathematical apparatus, is primarily, that it does not require for solve the problem of costly commercial software using finite element method. All calculations can be made for example in MS Excel, which is advantageous especially in the initial stages of constructing of spindle node for the rapid assessment of the suitability its design. After detailing the entire structure of spindle node is then also necessary to perform the refined dynamic analysis in the environment of FEM, which it requires the necessary skills and experience and it is therefore economically difficult. This work was developed within grant project KEGA No. 023TUKE-4/2012 Creation of a comprehensive educational - teaching material for the article Production technique using a combination of traditional and modern information technology and e-learning.

  1. Space Station Freedom environmental control and life support system phase 3 simplified integrated test detailed report

    NASA Technical Reports Server (NTRS)

    Roberts, B. C.; Carrasquillo, R. L.; Dubiel, M. Y.; Ogle, K. Y.; Perry, J. L.; Whitley, K. M.

    1990-01-01

    A description of the phase 3 simplified integrated test (SIT) conducted at the Marshall Space Flight Center (MSFC) Core Module Integration Facility (CMIF) in 1989 is presented. This was the first test in the phase 3 series integrated environmental control and life support systems (ECLSS) tests. The basic goal of the SIT was to achieve full integration of the baseline air revitalization (AR) subsystems for Space Station Freedom. Included is a description of the SIT configuration, a performance analysis of each subsystem, results from air and water sampling, and a discussion of lessons learned from the test. Also included is a full description of the preprototype ECLSS hardware used in the test.

  2. 26 CFR 1.41-9 - Alternative simplified credit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Alternative simplified credit. 1.41-9 Section 1.41-9 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY INCOME TAX INCOME TAXES Credits Against Tax § 1.41-9 Alternative simplified credit. For further guidance, see § 1.41-9T....

  3. 26 CFR 1.41-9 - Alternative simplified credit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 1 2011-04-01 2009-04-01 true Alternative simplified credit. 1.41-9 Section 1.41-9 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY INCOME TAX INCOME TAXES Credits Against Tax § 1.41-9 Alternative simplified credit. For further guidance, see § 1.41-9T....

  4. 26 CFR 1.41-9 - Alternative simplified credit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... June 9, 2011, see § 1.41-9T as contained in 26 CFR part 1, revised April 1, 2011. ... 26 Internal Revenue 1 2014-04-01 2013-04-01 true Alternative simplified credit. 1.41-9 Section 1... Credits Against Tax § 1.41-9 Alternative simplified credit. (a) Determination of credit. At the...

  5. 12 CFR 3.211 - Simplified supervisory formula approach (SSFA).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 1 2014-01-01 2014-01-01 false Simplified supervisory formula approach (SSFA). 3.211 Section 3.211 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY CAPITAL ADEQUACY STANDARDS Risk-Weighted Assets-Market Risk § 3.211 Simplified supervisory formula approach (SSFA). (a) General requirements. To use...

  6. 12 CFR 217.144 - Simplified supervisory formula approach (SSFA).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 2 2014-01-01 2014-01-01 false Simplified supervisory formula approach (SSFA... Simplified supervisory formula approach (SSFA). (a) General requirements for the SSFA. To use the SSFA to determine the risk weight for a securitization exposure, a Board-regulated institution must have data...

  7. 12 CFR 217.211 - Simplified supervisory formula approach (SSFA).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 2 2014-01-01 2014-01-01 false Simplified supervisory formula approach (SSFA... Simplified supervisory formula approach (SSFA). (a) General requirements. To use the SSFA to determine the... the weight for each exposure) total capital requirement of the underlying exposures calculated...

  8. 12 CFR 324.211 - Simplified supervisory formula approach (SSFA).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 5 2014-01-01 2014-01-01 false Simplified supervisory formula approach (SSFA). 324.211 Section 324.211 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION REGULATIONS AND STATEMENTS OF GENERAL POLICY CAPITAL ADEQUACY OF FDIC-SUPERVISED INSTITUTIONS Risk-Weighted Assets-Market Risk § 324.211 Simplified supervisory...

  9. 7 CFR 273.25 - Simplified Food Stamp Program.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 4 2014-01-01 2014-01-01 false Simplified Food Stamp Program. 273.25 Section 273.25 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM CERTIFICATION OF ELIGIBLE HOUSEHOLDS Program Alternatives § 273.25 Simplified...

  10. 7 CFR 273.25 - Simplified Food Stamp Program.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 4 2013-01-01 2013-01-01 false Simplified Food Stamp Program. 273.25 Section 273.25 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM CERTIFICATION OF ELIGIBLE HOUSEHOLDS Program Alternatives § 273.25 Simplified...

  11. 7 CFR 273.25 - Simplified Food Stamp Program.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false Simplified Food Stamp Program. 273.25 Section 273.25 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM CERTIFICATION OF ELIGIBLE HOUSEHOLDS § 273.25 Simplified Food Stamp Program....

  12. Naturally Simplified Input, Comprehension, and Second Language Acquisition.

    ERIC Educational Resources Information Center

    Ellis, Rod

    This article examines the concept of simplification in second language (SL) learning, reviewing research on the simplified input that both naturalistic and classroom SL learners receive. Research indicates that simplified input, particularly if derived from naturally occurring interactions, does aid comprehension but has not been shown to…

  13. 26 CFR 1.41-9 - Alternative simplified credit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... June 9, 2011, see § 1.41-9T as contained in 26 CFR part 1, revised April 1, 2011. ... 26 Internal Revenue 1 2013-04-01 2013-04-01 false Alternative simplified credit. 1.41-9 Section 1... Credits Against Tax § 1.41-9 Alternative simplified credit. (a) Determination of credit. At the...

  14. Communication: A simplified coupled-cluster Lagrangian for polarizable embedding.

    PubMed

    Krause, Katharina; Klopper, Wim

    2016-01-28

    A simplified coupled-cluster Lagrangian, which is linear in the Lagrangian multipliers, is proposed for the coupled-cluster treatment of a quantum mechanical system in a polarizable environment. In the simplified approach, the amplitude equations are decoupled from the Lagrangian multipliers and the energy obtained from the projected coupled-cluster equation corresponds to a stationary point of the Lagrangian. PMID:26827193

  15. Simplified models for heat transfer in rooms

    NASA Astrophysics Data System (ADS)

    Graca, Guilherme C. C. Carrilho Da

    Buildings protect their occupants from the outside environment. As a semi-enclosed environment, buildings tend to contain the internally generated heat and air pollutants, as well as the solar and conductive heat gains that can occur in the facade. In the warmer months of the year this generally leads to overheating, creating a need for a cooling system. Ventilation air replaces contaminated air in the building and is often used as the dominant medium for heat transfer between indoor and outdoor environments. The goal of the research presented in this thesis is to develop a better understanding of the important parameters in the performance of ventilation systems and to develop simplified convective heat transfer models. The general approach used in this study seeks to capture the dominant physical processes for these problems with first order accuracy, and develop simple models that show the correct system behavior trends. Dimensional analysis, in conjunction with simple momentum and energy conservation, scaled model experiments and numerical simulations, is used to improve airflow and heat transfer rate predictions in both single and multi room ventilation systems. This study includes the three commonly used room ventilation modes: mixing, displacement and cross-ventilation. A new modeling approach to convective heat transfer between the building and the outside is presented: the concept of equivalent room heat transfer coefficient. The new model quantifies the reduction in heat transfer between ventilation air and internal room surfaces caused by limited thermal capacity and temperature variation of the air for the three modes studied. Particular emphasis is placed on cross-ventilation, and on the development of a simple model to characterize the airflow patterns that occur in this case. The implementation of the models in a building thermal simulation software tool is presented as well as comparisons between model predictions, experimental results and complex

  16. Simplified coupling power model for fibers fusion

    NASA Astrophysics Data System (ADS)

    Saktioto, J.; Ali, J.; Fadhali, M.

    2009-09-01

    Fiber coupler fabrication used for an optical waveguide requires lossless power for an optimal application. The previous research coupled fibers were successfully fabricated by injecting hydrogen flow at 1 bar and fused slightly by unstable torch flame in the range of 800-1350°C. Optical parameters may vary significantly over wide range physical properties. Coupling coefficient and refractive index are estimated from the experimental result of the coupling ratio distribution from 1% to 75%. The change of geometrical fiber affects the normalized frequency V even for single mode fibers. V is derived and some parametric variations are performed on the left and right hand side of the coupling region. A partial power is modelled and derived using V, normalized lateral phase constant u, and normalized lateral attenuation constant, w through the second kind of modified Bessel function of the l order, which obeys the normal mode and normalized propagation constant b. Total power is maintained constant in order to comply with the energy conservation law. The power is integrated through V, u, and w over the pulling length of 7500 µm for 1-D. The core radius of a fiber significantly affects V and power partially at coupling region rather than wavelength and refractive index of core and cladding. This model has power phenomena in transmission and reflection for an optical switch and tunable filter.

  17. A Simplified Model of Tropical Cyclone Intensification

    NASA Astrophysics Data System (ADS)

    Schubert, W. H.

    2015-12-01

    An axisymmetric model of tropical cyclone intensification is presented. The model is based on Salmon's wave-vortex approximation, which can describe flows with high Rossby number and low Froude number. After introducing an additional approximation designed to filter propagating inertia-gravity waves, the problem is reduced to the prediction of potential vorticity (PV) and the inversion of this PV to obtain the balanced wind and mass fields. This PV prediction/inversion problem is solved analytically for two types of forcing: a two-region model in which there is nonzero forcing in the cyclone core and zero forcing in the far-field; a three-region model in which there is non-zero forcing in both the cyclone core and the eyewall, with zero forcing in the far-field. The solutions of the two-region model provide insight into why tropical cyclones can have long incubation times before rapid intensification and how the size of the mature vortex can be influenced by the size of the initial vortex. The solutions of the three-region model provide insight into the formation of hollow PV structures and the inward movement of angular momentum surfaces across the radius of maximum wind.

  18. Physiological Response to a Simplified Veno-Venous Perfusion-Induced Systemic Hyperthermia System

    PubMed Central

    Ballard-Croft, Cherry; Wang, Dongfang; Jones, Cameron; Sumpter, L. Ryan; Zhou, Xiaoqin; Thomas, Joe; Topaz, Stephen; Zwischenberger, Joseph B.

    2014-01-01

    Our original venovenous perfusion-induced systemic hyperthermia (vv-PISH) system appeared to significantly improve lung cancer patient survival, but was too complex with numerous dialysis problems. We tested a simplified vv-PISH circuit that includes the AvalonElite double lumen cannula, a modified heat exchanger, water heater/cooler, and a centrifugal pump. The purpose of this study was to evaluate this simplified vv-PISH system (without hemodialyzer) and to investigate the physiological response to whole body hyperthermia in pigs. We tested our vv-PISH circuit in healthy female adult swine (n= 7, 55-68 kg). The therapeutic core temperature (42°C), calculated as mean of rectal, bladder, and esophageal temperatures, was achieved in six swine. A maximum difference of 0.5°C was observed between the individual temperature sensor readings, indicating homogeneous heat distribution. Heart rate and mean arterial pressure were transiently altered, but were safely managed. A significant elevation in pulmonary artery pressure occurred during the heating phase, resulting in one pig death. In all other pigs, pulmonary artery pressure returned to physiologic values during the therapeutic phase. Arterial blood electrolytes were maintained without the need of a dialyzer. Major organ function was within normal parameters. The simplified vv-PISH circuit reliably delivered the hyperthermic dose with no need of dialysis. PMID:23085942

  19. Simplifying CEA through Excel, VBA, and Subeq

    NASA Technical Reports Server (NTRS)

    Foster, Ryan

    2004-01-01

    Many people use compound equilibrium programs for very different reasons, varying from refrigerators to light bulbs to rockets. A commonly used equilibrium program is CEA. CEA can take various inputs such as pressure, temperature, and volume along with numerous reactants and run them through equilibrium equations to obtain valuable output information, including products formed and their relative amounts. A little over a year ago, Bonnie McBride created the program subeq with the goal to simplify the calling of CEA. Subeq was also designed to be called by other programs, including Excel, through the use of Visual Basic for Applications (VBA). The largest advantage of using Excel is that it allows the user to input the information in a colorful and user-friendly environment while allowing VBA to run subeq, which is in the form of a FORTRAN DLL (Dynamic Link Library). Calling subeq in this form makes it much faster than if it were converted to VBA. Since subeq requires such large lists of reactant and product names, all of which can't be passed in as an array, subeq had to be changed to accept very long strings of reactants and products. To pass this string and adjust the transfer of input and output parameters, the subeq DLL had to be changed. One program that does this is Compaq Visual FORTRAN, which allows DLLs to be edited, debugged, and compiled. Compaq Visual FORTRAN uses FORTRAN 90/95, which has additional features to that of FORTRAN 77. My goals this summer include finishing up the excel spreadsheet of subeq, which I started last summer, and putting it on the Internet so that others can use it without having to download my spreadsheet. To finish up the spreadsheet I will need to work on debugging current options and problems. I will also work on making it as robust as possible, so that all errors that may arise will be clearly communicated to the user. New features will be added old ones will be changed as I receive comments from people using the spreadsheet

  20. Application of a simplified theory of ELF propagation to a simplified worldwide model of the ionosphere

    NASA Astrophysics Data System (ADS)

    Behroozi-Toosi, A. B.; Booker, H. G.

    1980-12-01

    The simplified theory of ELF wave propagation in the earth-ionosphere transmission lines developed by Booker (1980) is applied to a simplified worldwide model of the ionosphere. The theory, which involves the comparison of the local vertical refractive index gradient with the local wavelength in order to classify the altitude into regions of low and high gradient, is used for a model of electron and negative ion profiles in the D and E regions below 150 km. Attention is given to the frequency dependence of ELF propagation at a middle latitude under daytime conditions, the daytime latitude dependence of ELF propagation at the equinox, the effects of sunspot, seasonal and diurnal variations on propagation, nighttime propagation neglecting and including propagation above 100 km, and the effect on daytime ELF propagation of a sudden ionospheric disturbance. The numerical values obtained by the method for the propagation velocity and attenuation rate are shown to be in general agreement with the analytic Naval Ocean Systems Center computer program. It is concluded that the method employed gives more physical insights into propagation processes than any other method, while requiring less effort and providing maximal accuracy.

  1. Simplified models for dark matter searches at the LHC

    NASA Astrophysics Data System (ADS)

    Abdallah, Jalal; Araujo, Henrique; Arbey, Alexandre; Ashkenazi, Adi; Belyaev, Alexander; Berger, Joshua; Boehm, Celine; Boveia, Antonio; Brennan, Amelia; Brooke, Jim; Buchmueller, Oliver; Buckley, Matthew; Busoni, Giorgio; Calibbi, Lorenzo; Chauhan, Sushil; Daci, Nadir; Davies, Gavin; De Bruyn, Isabelle; De Jong, Paul; De Roeck, Albert; de Vries, Kees; Del Re, Daniele; De Simone, Andrea; Di Simone, Andrea; Doglioni, Caterina; Dolan, Matthew; Dreiner, Herbi K.; Ellis, John; Eno, Sarah; Etzion, Erez; Fairbairn, Malcolm; Feldstein, Brian; Flaecher, Henning; Feng, Eric; Fox, Patrick; Genest, Marie-Hélène; Gouskos, Loukas; Gramling, Johanna; Haisch, Ulrich; Harnik, Roni; Hibbs, Anthony; Hoh, Siewyan; Hopkins, Walter; Ippolito, Valerio; Jacques, Thomas; Kahlhoefer, Felix; Khoze, Valentin V.; Kirk, Russell; Korn, Andreas; Kotov, Khristian; Kunori, Shuichi; Landsberg, Greg; Liem, Sebastian; Lin, Tongyan; Lowette, Steven; Lucas, Robyn; Malgeri, Luca; Malik, Sarah; McCabe, Christopher; Mete, Alaettin Serhan; Morgante, Enrico; Mrenna, Stephen; Nakahama, Yu; Newbold, Dave; Nordstrom, Karl; Pani, Priscilla; Papucci, Michele; Pataraia, Sophio; Penning, Bjoern; Pinna, Deborah; Polesello, Giacomo; Racco, Davide; Re, Emanuele; Riotto, Antonio Walter; Rizzo, Thomas; Salek, David; Sarkar, Subir; Schramm, Steven; Skubic, Patrick; Slone, Oren; Smirnov, Juri; Soreq, Yotam; Sumner, Timothy; Tait, Tim M. P.; Thomas, Marc; Tomalin, Ian; Tunnell, Christopher; Vichi, Alessandro; Volansky, Tomer; Weiner, Neal; West, Stephen M.; Wielers, Monika; Worm, Steven; Yavin, Itay; Zaldivar, Bryan; Zhou, Ning; Zurek, Kathryn

    2015-09-01

    This document outlines a set of simplified models for dark matter and its interactions with Standard Model particles. It is intended to summarize the main characteristics that these simplified models have when applied to dark matter searches at the LHC, and to provide a number of useful expressions for reference. The list of models includes both ss-channel and tt-channel scenarios. For ss-channel, spin-0 and spin-1 mediations are discussed, and also realizations where the Higgs particle provides a portal between the dark and visible sectors. The guiding principles underpinning the proposed simplified models are spelled out, and some suggestions for implementation are presented.

  2. Development of Technologies on Innovative-Simplified Nuclear Power Plant Using High-Efficiency Steam Injectors (9) System Outline and Endurance Test of Low-Pressure Steam Injectors

    SciTech Connect

    Shuichi Ohmori; Michitsugu Mori; Shoji Goto; Tadashi Narabayashi; Chikako Iwaki; Yutaka Asanuma

    2006-07-01

    A Steam Injector (SI) is a simple, compact and passive pump and also acts as a high-performance direct-contact compact heater. This provides SI with capability to serve also as a direct-contact feedwater heater that heats up feedwater by using extracted steam from the turbine. We are developing technology for 'Innovative Simplified Nuclear Power Plants' in order to further improve the economy and safety of nuclear power plants. Our technology development aims to significantly simplify equipment and reduce physical quantities by applying 'High-Efficiency SI', which are applicable to a wide range of operation regimes beyond the performance and applicable range of existing SIs and enables unprecedented multistage and parallel operation, to the low-pressure feedwater heaters and Emergency Core Cooling Systems (ECCS) of nuclear power plants, as well as achieve high inherent safety to prevent severe accidents by keeping the core covered with water (a Severe Accident-Free Concept). The innovative-simplified nuclear power plant consists of a simplified feedwater heating system, a passive core injection system and a passive containment cooling system. This report describes the results of the endurance and performance tests of low-pressure SIs for feedwater heaters with Jet-deaerator and core injection system. A part of this report are fruits of research which is carried out by Tokyo Electric Power Company (TEPCO), Toshiba, and 7 Universities in Japan, funded from the Ministry of Economy, Trade and Industry (METI) of Japan as the national public research-funded program. (authors)

  3. Simplified circuit corrects faults in parallel binary information channels

    NASA Technical Reports Server (NTRS)

    Goldberg, J.

    1966-01-01

    Corrective circuit prevents the appearance of erroneous output signals from the possible failure of any single-channel element interconnected in parallel binary information channels. The circuit is simplified and economical because it does not use redundant channels.

  4. Photographic and drafting techniques simplify method of producing engineering drawings

    NASA Technical Reports Server (NTRS)

    Provisor, H.

    1968-01-01

    Combination of photographic and drafting techniques has been developed to simplify the preparation of three dimensional and dimetric engineering drawings. Conventional photographs can be converted to line drawings by making copy negatives on high contrast film.

  5. Modular chassis simplifies packaging and interconnecting of circuit boards

    NASA Technical Reports Server (NTRS)

    Arens, W. E.; Boline, K. G.

    1964-01-01

    A system of modular chassis structures has simplified the design for mounting a number of printed circuit boards. This design is structurally adaptable to computer and industrial control system applications.

  6. cFE/CFS (Core Flight Executive/Core Flight System)

    NASA Technical Reports Server (NTRS)

    Wildermann, Charles P.

    2008-01-01

    This viewgraph presentation describes in detail the requirements and goals of the Core Flight Executive (cFE) and the Core Flight System (CFS). The Core Flight Software System is a mission independent, platform-independent, Flight Software (FSW) environment integrating a reusable core flight executive (cFE). The CFS goals include: 1) Reduce time to deploy high quality flight software; 2) Reduce project schedule and cost uncertainty; 3) Directly facilitate formalized software reuse; 4) Enable collaboration across organizations; 5) Simplify sustaining engineering (AKA. FSW maintenance); 6) Scale from small instruments to System of Systems; 7) Platform for advanced concepts and prototyping; and 7) Common standards and tools across the branch and NASA wide.

  7. Elaboration of simplified vinca alkaloids and phomopsin hybrids.

    PubMed

    Ngo, Quoc Anh; Roussi, Fanny; Thoret, Sylviane; Guéritte, Françoise

    2010-03-01

    Nine simplified vinca alkaloids and phomospin A hybrids, in which vindoline moiety has been replaced by a simpler scaffold, have been elaborated to evaluate their activity on the inhibition of tubulin polymerization. This article deals with the synthesis of various simplified vinca alkaloids, using a stereoselective coupling of catharantine with reactive aromatic compounds and methanol as well as their subsequent condensation with a large peptide chain mimicking those of phomopsin A. Biological evaluation and molecular modeling studies are also reported. PMID:20659111

  8. A simplified dynamic model of the Space Shuttle main engine

    NASA Technical Reports Server (NTRS)

    Duyar, Ahmet; Eldem, Vasfi; Merrill, Walter; Guo, Ten-Huei

    1991-01-01

    A simplified model is presented of the space shuttle main engine (SSME) dynamics valid within the range of operation of the engine. This model is obtained by linking the linearized point models obtained at 25 different operating points of SSME. The simplified model was developed for use with a model-based diagnostic scheme for failure detection and diagnostics studies, as well as control design purposes.

  9. Simplified Correction Of Errors In Reed-Solomon Codes

    NASA Technical Reports Server (NTRS)

    Truong, T. K.; Hsu, I. S.; Eastman, W. L.; Reed, I. S.

    1990-01-01

    New decoder realized by simplified pipeline architecture. Simplified procedure for correction of errors and erasures in Reed-Solomon codes expected to result in simpler decoding equipment. Development widens commercial applicability of Reed-Solomon codes, used to correct bursts of errors in digital communication and recording systems. Improved decoder less complex. Made more regular, simple, and suitable for implementation in both VLSI and software.

  10. Simplified models for same-spin new physics scenarios

    NASA Astrophysics Data System (ADS)

    Edelhäuser, Lisa; Krämer, Michael; Sonneveld, Jory

    2015-04-01

    Simplified models are an important tool for the interpretation of searches for new physics at the LHC. They are defined by a small number of new particles together with a specific production and decay pattern. The simplified models adopted in the experimental analyses thus far have been derived from supersymmetric theories, and they have been used to set limits on supersymmetric particle masses. We investigate the applicability of such simplified supersymmetric models to a wider class of new physics scenarios, in particular those with same-spin Standard Model partners. We focus on the pair production of quark partners and analyze searches for jets and missing energy within a simplified supersymmetric model with scalar quarks and a simplified model with spin-1/2 quark partners. Despite sizable differences in the detection efficiencies due to the spin of the new particles, the limits on particle masses are found to be rather similar. We conclude that the supersymmetric simplified models employed in current experimental analyses also provide a reliable tool to constrain same-spin BSM scenarios.

  11. Dual-core antiresonant hollow core fibers.

    PubMed

    Liu, Xuesong; Fan, Zhongwei; Shi, Zhaohui; Ma, Yunfeng; Yu, Jin; Zhang, Jing

    2016-07-25

    In this work, dual-core antiresonant hollow core fibers (AR-HCFs) are numerically demonstrated, based on our knowledge, for the first time. Two fiber structures are proposed. One is a composite of two single-core nested nodeless AR-HCFs, exhibiting low confinement loss and a circular mode profile in each core. The other has a relatively simple structure, with a whole elliptical outer jacket, presenting a uniform and wide transmission band. The modal couplings of the dual-core AR-HCFs rely on a unique mechanism that transfers power through the air. The core separation and the gap between the two cores influence the modal coupling strength. With proper designs, both of the dual-core fibers can have low phase birefringence and short modal coupling lengths of several centimeters. PMID:27464191

  12. Rotating convective turbulence in Earth and planetary cores

    NASA Astrophysics Data System (ADS)

    Aurnou, J. M.; Calkins, M. A.; Cheng, J. S.; Julien, K.; King, E. M.; Nieves, D.; Soderlund, K. M.; Stellmach, S.

    2015-09-01

    An accurate description of turbulent core convection is necessary in order to build robust models of planetary core processes. Towards this end, we focus here on the physics of rapidly rotating convection. In particular, we present a closely coupled suite of advanced asymptotically-reduced theoretical models, efficient Cartesian direct numerical simulations (DNS) and laboratory experiments. Good convergence is demonstrated between these three approaches, showing that a comprehensive understanding of the dynamics appears to be within reach in our simplified rotating convection system. The goal of this paper is to review these findings, and to discuss their possible implications for planetary cores dynamics.

  13. Application of a Simplified Theory of ELF Propagation to a Simplified Worldwide Model of the Ionosphere

    NASA Astrophysics Data System (ADS)

    Behroozi-Toosi, Amir B.; Booker, Henry G.

    1983-05-01

    The approximate theory of ELF propagation in the Earth-ionosphere transmission line described by Booker (1980) is applied to a simplified worldwide model of the D and E regions, and of the Earth's magnetic field. At 1000 Hz by day, reflection is primarily from the gradient on the underside of the D region. At 300 Hz by day, reflection is primarily from the D region at low latitudes, but it is from the E region at high latitudes. Below 100 Hz by day, reflection is primarily from the gradient on the underside of the E region at all latitudes. By night, reflection from the gradient on the topside of the E region is important. There is then a resonant frequency (˜ 300 Hz) at which the optical thickness of the E region for the whistler mode is half a wavelength. At the Schumann resonant frequency in the Earth-ionosphere cavity (˜ 8 Hz) the nocturnal E region is almost completely transparent for the whistler mode and is semi-transparent for the Alfvén mode. Reflection then takes place from the F region. ELF propagation in the Earth-ionosphere transmission line by night is quite dependent on the magnitude of the drop in ionization density between the E and F regions. Nocturnal propagation at ELF therefore depends significantly on an ionospheric feature whose magnitude and variability are not well understood. A comparison is made with results based on the computer program of the United States Naval Ocean Systems Center.

  14. Core-core and core-valence correlation

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.

    1988-01-01

    The effect of (1s) core correlation on properties and energy separations was analyzed using full configuration-interaction (FCI) calculations. The Be 1 S - 1 P, the C 3 P - 5 S and CH+ 1 Sigma + or - 1 Pi separations, and CH+ spectroscopic constants, dipole moment and 1 Sigma + - 1 Pi transition dipole moment were studied. The results of the FCI calculations are compared to those obtained using approximate methods. In addition, the generation of atomic natural orbital (ANO) basis sets, as a method for contracting a primitive basis set for both valence and core correlation, is discussed. When both core-core and core-valence correlation are included in the calculation, no suitable truncated CI approach consistently reproduces the FCI, and contraction of the basis set is very difficult. If the (nearly constant) core-core correlation is eliminated, and only the core-valence correlation is included, CASSCF/MRCI approached reproduce the FCI results and basis set contraction is significantly easier.

  15. A Simplified Model of The Electrical Asymmetry Effect

    NASA Astrophysics Data System (ADS)

    Keil, Douglas L.; Augustyniak, Edward; Sakiyama, Yukinori; Ni, Pavel

    2014-10-01

    Dual Frequency Capacitively Coupled Plasmas (DF CCP) have been used extensively in semiconductor processing. One of the most promising methods for extending CCP technology is the application of the Electrical Asymmetry Effect (EAE). Extensive studies of this effect have appeared in the literature and the effect can be claimed to be reasonably well understood. However, the complexity of the available models often makes them unwieldy for resolving engineering issues and for analysis of test data. In this work it is shown that most of the industrially important features of the EAE effect can be captured with a greatly simplified model. Although approximate, this simplified model enables relatively quick design guidance and simplifies analysis of test data. Electrical measurements of the EAE effect from a commercially relevant CCP plasma deposition tool are presented. These results show good agreement with the model and serve to illustrate the basic features of the model.

  16. Simplified Analysis Model for Predicting Pyroshock Responses on Composite Panel

    NASA Astrophysics Data System (ADS)

    Iwasa, Takashi; Shi, Qinzhong

    A simplified analysis model based on the frequency response analysis and the wave propagation analysis was established for predicting Shock Response Spectrum (SRS) on the composite panel subjected to pyroshock loadings. The complex composite panel was modeled as an isotropic single layer panel defined in NASA Lewis Method. Through the conductance of an impact excitation test on a composite panel with no equipment mounted on, it was presented that the simplified analysis model could estimate the SRS as well as the acceleration peak values in both near and far field in an accurate way. In addition, through the simulation for actual pyroshock tests on an actual satellite system, the simplified analysis model was proved to be applicable in predicting the actual pyroshock responses, while bringing forth several technical issues to estimate the pyroshock test specifications in early design stages.

  17. A simplified model for two phase face seal design

    NASA Technical Reports Server (NTRS)

    Lau, S. Y.; Hughes, W. F.; Basu, P.; Beatty, P. A.

    1990-01-01

    A simplified quasi-isothermal low-leakage laminar model for analyzing the stiffness and the stability characteristics of two-phase face seals with real fluids is developed. Sample calculations with this model for low-leakage operations are compared with calculations for high-leakage operations, performed using the adiabatic turbulent model of Beatty and Hughes (1987). It was found that the seal characteristics predicted using the two extreme models tend to overlap with each other, indicating that the simplified laminar model may be a useful tool for seal design. The effect of coning was investigated using the simplified model. The results show that, for the same balance, a coned seal has a higher leakage rate than a parallel face seal.

  18. A simplified method for elastic-plastic-creep structural analysis

    NASA Technical Reports Server (NTRS)

    Kaufman, A.

    1985-01-01

    A simplified inelastic analysis computer program (ANSYPM) was developed for predicting the stress-strain history at the critical location of a thermomechanically cycled structure from an elastic solution. The program uses an iterative and incremental procedure to estimate the plastic strains from the material stress-strain properties and a plasticity hardening model. Creep effects are calculated on the basis of stress relaxation at constant strain, creep at constant stress or a combination of stress relaxation and creep accumulation. The simplified method was exercised on a number of problems involving uniaxial and multiaxial loading, isothermal and nonisothermal conditions, dwell times at various points in the cycles, different materials and kinematic hardening. Good agreement was found between these analytical results and nonlinear finite element solutions for these problems. The simplified analysis program used less than 1 percent of the CPU time required for a nonlinear finite element analysis.

  19. A simplified method for elastic-plastic-creep structural analysis

    NASA Technical Reports Server (NTRS)

    Kaufman, A.

    1984-01-01

    A simplified inelastic analysis computer program (ANSYPM) was developed for predicting the stress-strain history at the critical location of a thermomechanically cycled structure from an elastic solution. The program uses an iterative and incremental procedure to estimate the plastic strains from the material stress-strain properties and a plasticity hardening model. Creep effects are calculated on the basis of stress relaxation at constant strain, creep at constant stress or a combination of stress relaxation and creep accumulation. The simplified method was exercised on a number of problems involving uniaxial and multiaxial loading, isothermal and nonisothermal conditions, dwell times at various points in the cycles, different materials and kinematic hardening. Good agreement was found between these analytical results and nonlinear finite element solutions for these problems. The simplified analysis program used less than 1 percent of the CPU time required for a nonlinear finite element analysis.

  20. Development of a simplified procedure for cyclic structural analysis

    NASA Technical Reports Server (NTRS)

    Kaufman, A.

    1984-01-01

    Development was extended of a simplified inelastic analysis computer program (ANSYMP) for predicting the stress-strain history at the critical location of a thermomechanically cycled structure from an elastic solution. The program uses an iterative and incremental procedure to estimate the plastic strains from the material stress-strain properties and a plasticity hardening model. Creep effects can be calculated on the basis of stress relaxation at constant strain, creep at constant stress, or a combination of stress relaxation and creep accumulation. The simplified method was exercised on a number of problems involving uniaxial and multiaxial loading, isothermal and nonisothermal conditions, dwell times at various points in the cycles, different materials, and kinematic hardening. Good agreement was found between these analytical results and nonlinear finite-element solutions for these problems. The simplified analysis program used less than 1 percent of the CPU time required for a nonlinear finite-element analysis.

  1. Demonstration of fully coupled simplified extended station black-out accident simulation with RELAP-7

    SciTech Connect

    Zhao, Haihua; Zhang, Hongbin; Zou, Ling; Anders, David; Martineau, Richard

    2014-10-01

    The RELAP-7 code is the next generation nuclear reactor system safety analysis code being developed at the Idaho National Laboratory (INL). The RELAP-7 code develop-ment effort started in October of 2011 and by the end of the second development year, a number of physical components with simplified two phase flow capability have been de-veloped to support the simplified boiling water reactor (BWR) extended station blackout (SBO) analyses. The demonstration case includes the major components for the primary system of a BWR, as well as the safety system components for the safety relief valve (SRV), the reactor core isolation cooling (RCIC) system, and the wet well. Three scenar-ios for the SBO simulations have been considered. Since RELAP-7 is not a severe acci-dent analysis code, the simulation stops when fuel clad temperature reaches damage point. Scenario I represents an extreme station blackout accident without any external cooling and cooling water injection. The system pressure is controlled by automatically releasing steam through SRVs. Scenario II includes the RCIC system but without SRV. The RCIC system is fully coupled with the reactor primary system and all the major components are dynamically simulated. The third scenario includes both the RCIC system and the SRV to provide a more realistic simulation. This paper will describe the major models and dis-cuss the results for the three scenarios. The RELAP-7 simulations for the three simplified SBO scenarios show the importance of dynamically simulating the SRVs, the RCIC sys-tem, and the wet well system to the reactor safety during extended SBO accidents.

  2. Simplified pregnant woman models for the fetus exposure assessment

    NASA Astrophysics Data System (ADS)

    Jala, Marjorie; Conil, Emmanuelle; Varsier, Nadège; Wiart, Joe; Hadjem, Abdelhamid; Moulines, Éric; Lévy-Leduc, Céline

    2013-05-01

    In this paper, we introduce a study that we carried out in order to validate the use of a simplified pregnant woman model for the assessment of the fetus exposure to radio frequency waves. This simplified model, based on the use of a homogeneous tissue to replace most of the inner organs of the virtual mother, would allow us to deal with many issues that are raised because of the lack of pregnant woman models for numerical dosimetry. Using specific absorption rate comparisons, we show that this model could be used to estimate the fetus exposure to plane waves.

  3. A simplified dynamic model of the T700 turboshaft engine

    NASA Technical Reports Server (NTRS)

    Duyar, Ahmet; Gu, Zhen; Litt, Jonathan S.

    1992-01-01

    A simplified open-loop dynamic model of the T700 turboshaft engine, valid within the normal operating range of the engine, is developed. This model is obtained by linking linear state space models obtained at different engine operating points. Each linear model is developed from a detailed nonlinear engine simulation using a multivariable system identification and realization method. The simplified model may be used with a model-based real time diagnostic scheme for fault detection and diagnostics, as well as for open loop engine dynamics studies and closed loop control analysis utilizing a user generated control law.

  4. Simulation and simplified design studies of photovoltaic systems

    SciTech Connect

    Evans, D.L.; Facinelli, W.A.; Koehler, L.P.

    1980-09-01

    Results of TRNSYS simulations of photovoltaic systems with electrical storage are described. Studies of the sensitivity of system performance, in terms of the fraction of the electrical load supplied by the solar energy system, to variables such as array size, battery size, location, time of year, and load shape are reported. An accurate simplified method for predicting array output of max-power photovoltaic systems is presented. A second simplified method, which estimates the overall performance of max-power systems, is developed. Finally, a preliminary technique for predicting clamped-voltage system performance is discussed.

  5. Simplified ontologies allowing comparison of developmental mammalian gene expression

    PubMed Central

    Kruger, Adele; Hofmann, Oliver; Carninci, Piero; Hayashizaki, Yoshihide; Hide, Winston

    2007-01-01

    Model organisms represent an important resource for understanding the fundamental aspects of mammalian biology. Mapping of biological phenomena between model organisms is complex and if it is to be meaningful, a simplified representation can be a powerful means for comparison. The Developmental eVOC ontologies presented here are simplified orthogonal ontologies describing the temporal and spatial distribution of developmental human and mouse anatomy. We demonstrate the ontologies by identifying genes showing a bias for developmental brain expression in human and mouse. PMID:17961239

  6. Simplifying Probability Elicitation and Uncertainty Modeling in Bayesian Networks

    SciTech Connect

    Paulson, Patrick R; Carroll, Thomas E; Sivaraman, Chitra; Neorr, Peter A; Unwin, Stephen D; Hossain, Shamina S

    2011-04-16

    In this paper we contribute two methods that simplify the demands of knowledge elicitation for particular types of Bayesian networks. The first method simplify the task of providing probabilities when the states that a random variable takes can be described by a new, fully ordered state set in which a state implies all the preceding states. The second method leverages Dempster-Shafer theory of evidence to provide a way for the expert to express the degree of ignorance that they feel about the estimates being provided.

  7. The simplified reference tissue model: model assumption violations and their impact on binding potential.

    PubMed

    Salinas, Cristian A; Searle, Graham E; Gunn, Roger N

    2015-02-01

    Reference tissue models have gained significant traction over the last two decades as the methods of choice for the quantification of brain positron emission tomography data because they balance quantitative accuracy with less invasive procedures. The principal advantage is the elimination of the need to perform arterial cannulation of the subject to measure blood and metabolite concentrations for input function generation. In particular, the simplified reference tissue model (SRTM) has been widely adopted as it uses a simplified model configuration with only three parameters that typically produces good fits to the kinetic data and a stable parameter estimation process. However, the model's simplicity and its ability to generate good fits to the data, even when the model assumptions are not met, can lead to misplaced confidence in binding potential (BPND) estimates. Computer simulation were used to study the bias introduced in BPND estimates as a consequence of violating each of the four core SRTM model assumptions. Violation of each model assumption led to bias in BPND (both over and underestimation). Careful assessment of the bias in SRTM BPND should be performed for new tracers and applications so that an appropriate decision about its applicability can be made. PMID:25425078

  8. The simplified reference tissue model: model assumption violations and their impact on binding potential

    PubMed Central

    Salinas, Cristian A; Searle, Graham E; Gunn, Roger N

    2015-01-01

    Reference tissue models have gained significant traction over the last two decades as the methods of choice for the quantification of brain positron emission tomography data because they balance quantitative accuracy with less invasive procedures. The principal advantage is the elimination of the need to perform arterial cannulation of the subject to measure blood and metabolite concentrations for input function generation. In particular, the simplified reference tissue model (SRTM) has been widely adopted as it uses a simplified model configuration with only three parameters that typically produces good fits to the kinetic data and a stable parameter estimation process. However, the model's simplicity and its ability to generate good fits to the data, even when the model assumptions are not met, can lead to misplaced confidence in binding potential (BPND) estimates. Computer simulation were used to study the bias introduced in BPND estimates as a consequence of violating each of the four core SRTM model assumptions. Violation of each model assumption led to bias in BPND (both over and underestimation). Careful assessment of the bias in SRTM BPND should be performed for new tracers and applications so that an appropriate decision about its applicability can be made. PMID:25425078

  9. Simplifying the Admissions Process: Legitimate Endeavor or Recruiting Gimmick?

    ERIC Educational Resources Information Center

    Bruker, Robert M.

    1977-01-01

    Improbable as it may seem, some admissions officers have been able to increase the size of their applicant pool; more effectively identify and serve student needs; and simplify their admissions process--all at the same time, and without increasing their office work load. (Author)

  10. A Simplified Diagnostic Method for Elastomer Bond Durability

    NASA Technical Reports Server (NTRS)

    White, Paul

    2009-01-01

    A simplified method has been developed for determining bond durability under exposure to water or high humidity conditions. It uses a small number of test specimens with relatively short times of water exposure at elevated temperature. The method is also gravimetric; the only equipment being required is an oven, specimen jars, and a conventional laboratory balance.

  11. A Simplified Decision Support Approach for Evaluating Wetlands Ecosystem Services

    EPA Science Inventory

    We will be presenting a simplified approach to evaluating ecosystem services provided by freshwater wetlands restoration. Our approach is based on an existing functional assessment approach developed by Golet and Miller for the State of Rhode Island, and modified by Miller for ap...

  12. A Simplified Technique for Evaluating Human "CCR5" Genetic Polymorphism

    ERIC Educational Resources Information Center

    Falteisek, Lukáš; Cerný, Jan; Janštová, Vanda

    2013-01-01

    To involve students in thinking about the problem of AIDS (which is important in the view of nondecreasing infection rates), we established a practical lab using a simplified adaptation of Thomas's (2004) method to determine the polymorphism of HIV co-receptor CCR5 from students' own epithelial cells. CCR5 is a receptor involved in…

  13. SIMPLIFIED RADIOIMMUNOASSAY FOR DETECTION OF HUMAN ROTAVIRUS IN STOOLS

    EPA Science Inventory

    A simplified radioimmunoassay (RIA) technique was developed to facilitate the diagnosis of human rotavirus in stools of infants with diarrhea. This microtiter solid-phase RIA utilizes as a critical reagent hyperimmune serum against a tissue culture-grown simian rotavirus that is ...

  14. Simplified Load-Following Control for a Fuel Cell System

    NASA Technical Reports Server (NTRS)

    Vasquez, Arturo

    2010-01-01

    A simplified load-following control scheme has been proposed for a fuel cell power system. The scheme could be used to control devices that are important parts of a fuel cell system but are sometimes characterized as parasitic because they consume some of the power generated by the fuel cells.

  15. Simplify Web Development for Faculty and Promote Instructional Design.

    ERIC Educational Resources Information Center

    Pedersen, David C.

    Faculty members are often overwhelmed with the prospect of implementing Web-based instruction. In an effort to simplify the process and incorporate some basic instructional design elements, the Educational Technology Team at Embry Riddle Aeronautical University created a course template for WebCT. Utilizing rapid prototyping, the template…

  16. Flat pack interconnection structure simplifies modular electronic assemblies

    NASA Technical Reports Server (NTRS)

    Katzin, L.

    1967-01-01

    Flat pack interconnection structure composed of stick modules simplifies modular electronic assemblies by allowing a single axis mother board. Two of the wiring planes are located in the stick module, which is the lower level of assembly, with the third wiring plane in the mother board.

  17. 12 CFR 3.144 - Simplified supervisory formula approach (SSFA).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 1 2014-01-01 2014-01-01 false Simplified supervisory formula approach (SSFA). 3.144 Section 3.144 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY CAPITAL ADEQUACY STANDARDS Risk-Weighted Assets-Internal Ratings-Based and Advanced Measurement Approaches Risk-Weighted Assets for...

  18. 12 CFR 324.144 - Simplified supervisory formula approach (SSFA).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 5 2014-01-01 2014-01-01 false Simplified supervisory formula approach (SSFA). 324.144 Section 324.144 Banks and Banking FEDERAL DEPOSIT INSURANCE CORPORATION REGULATIONS AND STATEMENTS OF GENERAL POLICY CAPITAL ADEQUACY OF FDIC-SUPERVISED INSTITUTIONS Risk-Weighted Assets-Internal Ratings-Based and Advanced...

  19. 7 CFR 273.25 - Simplified Food Stamp Program.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... TANF plan as defined at 45 CFR 260.30. (3) Pure-TANF household means a household in which all members... CFR 260.31. (b) Limit on benefit reduction for mixed-TANF households under the SFSP. If a State agency... 7 Agriculture 4 2011-01-01 2011-01-01 false Simplified Food Stamp Program. 273.25 Section...

  20. 7 CFR 273.25 - Simplified Food Stamp Program.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... TANF plan as defined at 45 CFR 260.30. (3) Pure-TANF household means a household in which all members... CFR 260.31. (b) Limit on benefit reduction for mixed-TANF households under the SFSP. If a State agency... 7 Agriculture 4 2012-01-01 2012-01-01 false Simplified Food Stamp Program. 273.25 Section...

  1. Simplified seismic performance assessment and implications for seismic design

    NASA Astrophysics Data System (ADS)

    Sullivan, Timothy J.; Welch, David P.; Calvi, Gian Michele

    2014-08-01

    The last decade or so has seen the development of refined performance-based earthquake engineering (PBEE) approaches that now provide a framework for estimation of a range of important decision variables, such as repair costs, repair time and number of casualties. This paper reviews current tools for PBEE, including the PACT software, and examines the possibility of extending the innovative displacement-based assessment approach as a simplified structural analysis option for performance assessment. Details of the displacement-based s+eismic assessment method are reviewed and a simple means of quickly assessing multiple hazard levels is proposed. Furthermore, proposals for a simple definition of collapse fragility and relations between equivalent single-degree-of-freedom characteristics and multi-degree-of-freedom story drift and floor acceleration demands are discussed, highlighting needs for future research. To illustrate the potential of the methodology, performance measures obtained from the simplified method are compared with those computed using the results of incremental dynamic analyses within the PEER performance-based earthquake engineering framework, applied to a benchmark building. The comparison illustrates that the simplified method could be a very effective conceptual seismic design tool. The advantages and disadvantages of the simplified approach are discussed and potential implications of advanced seismic performance assessments for conceptual seismic design are highlighted through examination of different case study scenarios including different structural configurations.

  2. Cataloguing, Classification and Processing. A Simplified Guide for School Libraries.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education, Winnipeg.

    Designed for use in school libraries, this manual outlines simplified procedures for cataloging, defined as the indexing of an item; for classification, defined as the assignment of a subject number to the item; and for processsing, defined as the preparation of the item so that it can be borrowed from the library. The manual is divided into 10…

  3. 46 CFR 178.330 - Simplified stability proof test (SST).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Intact Stability Standards § 178.330 Simplified... a flush deck or well deck vessel, the freeboard must be measured to the top of the weatherdeck at... measured to the top of the gunwale. (g) A ferry must also be tested in a manner acceptable to the...

  4. 46 CFR 178.330 - Simplified stability proof test (SST).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Intact Stability Standards § 178.330 Simplified... a flush deck or well deck vessel, the freeboard must be measured to the top of the weatherdeck at... measured to the top of the gunwale. (g) A ferry must also be tested in a manner acceptable to the...

  5. 46 CFR 178.330 - Simplified stability proof test (SST).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Intact Stability Standards § 178.330 Simplified... a flush deck or well deck vessel, the freeboard must be measured to the top of the weatherdeck at... measured to the top of the gunwale. (g) A ferry must also be tested in a manner acceptable to the...

  6. 46 CFR 178.330 - Simplified stability proof test (SST).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (UNDER 100 GROSS TONS) INTACT STABILITY AND SEAWORTHINESS Intact Stability Standards § 178.330 Simplified... a flush deck or well deck vessel, the freeboard must be measured to the top of the weatherdeck at... measured to the top of the gunwale. (g) A ferry must also be tested in a manner acceptable to the...

  7. A simplified ductile-brittle transition temperature tester

    NASA Technical Reports Server (NTRS)

    Arias, A.

    1973-01-01

    The construction and operation of a versatile, simplified bend tester is described. The tester is usable at temperatures from - 192 to 650 C in air. Features of the tester include a single test chamber for cryogenic or elevated temperatures, specimen alining support rollers, and either manual or motorized operation.

  8. Tricuspid balloon valvuloplasty: a more simplified approach using inoue balloon.

    PubMed

    Patel, T M; Dani, S I; Shah, S C; Patel, T K

    1996-01-01

    We report a more simplified technique of the balloon tricuspid valvuloplasty using inoue balloon set in a patient suffering from severe rheumatic tricuspid stenosis. We believe that this technique may be useful in a difficult case of tricuspid valvuloplasty. PMID:8770490

  9. Simplified physically based model of earthen embankment breaching

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A simplified physically based model has been developed to simulate the breaching processes of homogenous and composite earthen embankments owing to overtopping and piping. The breach caused by overtopping flow is approximated as a flat broad-crested weir with a trapezoidal cross section, downstream ...

  10. Measuring Phantom Recollection in the Simplified Conjoint Recognition Paradigm

    ERIC Educational Resources Information Center

    Stahl, Christoph; Klauer, Karl Christoph

    2009-01-01

    False memories are sometimes strong enough to elicit recollective experiences. This phenomenon has been termed Phantom Recollection (PR). The Conjoint Recognition (CR) paradigm has been used to empirically separate PR from other memory processes. Recently, a simplification of the CR procedure has been proposed. We herein extend the simplified CR…

  11. The Choice of Traditional vs. Simplified Characters in US Classrooms

    ERIC Educational Resources Information Center

    Deng, Shi-zhong

    2009-01-01

    Which form of Chinese characters should be taught in Chinese language classes: traditional or simplified? The results of a questionnaire distributed to sections at the University of Florida show the reasons for students' preferences for one or the other form. In view of the students' awareness that traditional characters are more beneficial to…

  12. A Linguistic Analysis of Simplified and Authentic Texts

    ERIC Educational Resources Information Center

    Crossley, Scott A.; Louwerse, Max M.; McCarthy, Philip M.; McNamara, Danielle S.

    2007-01-01

    The opinions of second language learning (L2) theorists and researchers are divided over whether to use authentic or simplified reading texts as the means of input for beginning- and intermediate-level L2 learners. Advocates of both approaches cite the use of linguistic features, syntax, and discourse structures as important elements in support of…

  13. Investigations in a Simplified Bracketed Grid Approach to Metrical Structure

    ERIC Educational Resources Information Center

    Liu, Patrick Pei

    2010-01-01

    In this dissertation, I examine the fundamental mechanisms and assumptions of the Simplified Bracketed Grid Theory (Idsardi 1992) in two ways: first, by comparing it with Parametric Metrical Theory (Hayes 1995), and second, by implementing it in the analysis of several case studies in stress assignment and syllabification. Throughout these…

  14. Academic Rigor: The Core of the Core

    ERIC Educational Resources Information Center

    Brunner, Judy

    2013-01-01

    Some educators see the Common Core State Standards as reason for stress, most recognize the positive possibilities associated with them and are willing to make the professional commitment to implementing them so that academic rigor for all students will increase. But business leaders, parents, and the authors of the Common Core are not the only…

  15. On Simplifying Features in OpenStreetMap database

    NASA Astrophysics Data System (ADS)

    Qian, Xinlin; Tao, Kunwang; Wang, Liang

    2015-04-01

    Currently the visualization of OpenStreetMap data is using a tile server which stores map tiles that have been rendered from vector data in advance. However, tiled map are short of functionalities such as data editing and customized styling. To enable these advanced functionality, Client-side processing and rendering of geospatial data is needed. Considering the voluminous size of the OpenStreetMap data, simply sending region queries results of OSM database to client is prohibitive. To make the OSM data retrieved from database adapted for client receiving and rendering, It must be filtered and simplified at server-side to limit its volume. We propose a database extension for OSM database to make it possible to simplifying geospatial objects such as ways and relations during data queries. Several auxiliary tables and PL/pgSQL functions are presented to make the geospatial features can be simplified by omitting unimportant vertices. There are five components in the database extension: Vertices weight computation by polyline and polygon simplification algorithm, Vertices weight storage in auxiliary tables. filtering and selecting of vertices using specific threshold value during spatial queries, assembling of simplified geospatial objects using filtered vertices, vertices weight updating after geospatial objects editing. The database extension is implemented on an OSM APIDB using PL/pgSQL. The database contains a subset of OSM database. The experimental database contains geographic data of United Kingdom which is about 100 million vertices and roughly occupy 100GB disk. JOSM are used to retrieve the data from the database using a revised data accessing API and render the geospatial objects in real-time. When serving simplified data to client, The database allows user to set the bound of the error of simplification or the bound of responding time in each data query. Experimental results show the effectiveness and efficiency of the proposed methods in building a

  16. CFD Analysis of Core Bypass Phenomena

    SciTech Connect

    Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

    2010-03-01

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the sector grid can be set as a symmetry boundary

  17. CFD Analysis of Core Bypass Phenomena

    SciTech Connect

    Richard W. Johnson; Hiroyuki Sato; Richard R. Schultz

    2009-11-01

    The U.S. Department of Energy is exploring the potential for the VHTR which will be either of a prismatic or a pebble-bed type. One important design consideration for the reactor core of a prismatic VHTR is coolant bypass flow which occurs in the interstitial regions between fuel blocks. Such gaps are an inherent presence in the reactor core because of tolerances in manufacturing the blocks and the inexact nature of their installation. Furthermore, the geometry of the graphite blocks changes over the lifetime of the reactor because of thermal expansion and irradiation damage. The existence of the gaps induces a flow bias in the fuel blocks and results in unexpected increase of maximum fuel temperature. Traditionally, simplified methods such as flow network calculations employing experimental correlations are used to estimate flow and temperature distributions in the core design. However, the distribution of temperature in the fuel pins and graphite blocks as well as coolant outlet temperatures are strongly coupled with the local heat generation rate within fuel blocks which is not uniformly distributed in the core. Hence, it is crucial to establish mechanistic based methods which can be applied to the reactor core thermal hydraulic design and safety analysis. Computational Fluid Dynamics (CFD) codes, which have a capability of local physics based simulation, are widely used in various industrial fields. This study investigates core bypass flow phenomena with the assistance of commercial CFD codes and establishes a baseline for evaluation methods. A one-twelfth sector of the hexagonal block surface is modeled and extruded down to whole core length of 10.704m. The computational domain is divided vertically with an upper reflector, a fuel section and a lower reflector. Each side of the one-twelfth grid can be set as a symmetry boundary

  18. On the joint inversion of geophysical data for models of the coupled core-mantle system

    NASA Technical Reports Server (NTRS)

    Voorhies, Coerte V.

    1991-01-01

    Joint inversion of magnetic, earth rotation, geoid, and seismic data for a unified model of the coupled core-mantle system is proposed and shown to be possible. A sample objective function is offered and simplified by targeting results from independent inversions and summary travel time residuals instead of original observations. These data are parameterized in terms of a very simple, closed model of the topographically coupled core-mantle system. Minimization of the simplified objective function leads to a nonlinear inverse problem; an iterative method for solution is presented. Parameterization and method are emphasized; numerical results are not presented.

  19. The Core Skills Initiative.

    ERIC Educational Resources Information Center

    Further Education Unit, London (England).

    A British initiative that aims to identify, develop, and assess core skills in post-16 courses and qualifications is summarized in this bulletin. The first section discusses expectations regarding what core skills can achieve. The following section focuses on other purposes to which core skills could contribute, such as broadening the post-16…

  20. Core Competence and Education.

    ERIC Educational Resources Information Center

    Holmes, Gary; Hooper, Nick

    2000-01-01

    Outlines the concept of core competence and applies it to postcompulsory education in the United Kingdom. Adopts an educational perspective that suggests accreditation as the core competence of universities. This economic approach suggests that the market trend toward lifetime learning might best be met by institutions developing a core competence…

  1. Core Design Applications

    Energy Science and Technology Software Center (ESTSC)

    1995-07-12

    CORD-2 is intended for core desigh applications of pressurized water reactors. The main objective was to assemble a core design system which could be used for simple calculations (such as frequently required for fuel management) as well as for accurate calculations (for example, core design after refueling).

  2. Coring Sample Acquisition Tool

    NASA Technical Reports Server (NTRS)

    Haddad, Nicolas E.; Murray, Saben D.; Walkemeyer, Phillip E.; Badescu, Mircea; Sherrit, Stewart; Bao, Xiaoqi; Kriechbaum, Kristopher L.; Richardson, Megan; Klein, Kerry J.

    2012-01-01

    A sample acquisition tool (SAT) has been developed that can be used autonomously to sample drill and capture rock cores. The tool is designed to accommodate core transfer using a sample tube to the IMSAH (integrated Mars sample acquisition and handling) SHEC (sample handling, encapsulation, and containerization) without ever touching the pristine core sample in the transfer process.

  3. Neutrino-driven turbulent convection in stalled supernova cores

    NASA Astrophysics Data System (ADS)

    Radice, David; Ott, Christian; Abdikamalov, Ernazar; Couch, Sean; Haas, Roland; Schnetter, Erik

    2015-04-01

    The dynamics of neutrino-driven turbulent convection, in the quasi-steady phases of a core-collapse supernova explosion following the shock stall, is emerging as being of crucial importance in aiding, or hindering, a successful explosion. In this talk I will present some recent and ongoing numerical studies done with the goal of of a) characterizing neutrino-driven convection in a simplified setting and b) understanding finite numerical resolution effects in more realistic explosion models.

  4. A simplified model of heat transfer in heat exchangers and stack plates of thermoacoustic refrigerators

    NASA Astrophysics Data System (ADS)

    Herman, Cila; Chen, Yuwen

    2006-08-01

    A simplified model of heat transfer was developed to investigate the thermal behavior of heat exchangers and stack plates of thermoacoustic devices. The model took advantage of previous results describing the thermal behavior of the thermoacoustic core and heat transfer in oscillating flow to study the performance of heat exchangers attached to the core. The configuration considered is a flat tube (with a working fluid flowing in the tube) of the thickness of the stack plate attached to both ends of the stack plate. Geometrical and operational parameters as well as thermophysical properties of the heat exchangers, transport fluids in the heat exchangers, stack plate and the thermoacoustic working fluid were organized into dimensionless groups that allowed accounting for their impact on the performance of the heat exchangers. Two types of thermal boundary conditions were considered: constant temperature and constant heat flux along the heat exchanger tubes. Numerical simulations were carried out with the model introduced in the paper. The temperature distributions and heat fluxes near the edge of the stack plate were found to be nonlinear. The influence of system parameters on the thermal performance of the heat exchangers was analyzed.

  5. Simplified slow anti-coincidence circuit for Compton suppression systems.

    PubMed

    Al-Azmi, Darwish

    2008-08-01

    Slow coincidence circuits for the anti-coincidence measurements have been considered for use in Compton suppression technique. The simplified version of the slow circuit has been found to be fast enough, satisfactory and allows an easy system setup, particularly with the advantage of the automatic threshold setting of the low-level discrimination. A well-type NaI detector as the main detector surrounded by plastic guard detector has been arranged to investigate the performance of the Compton suppression spectrometer using the simplified slow circuit. The system has been tested to observe the improvement in the energy spectra for medium to high-energy gamma-ray photons from terrestrial and environmental samples. PMID:18222698

  6. Simplified scheme for entanglement preparation with Rydberg pumping via dissipation

    NASA Astrophysics Data System (ADS)

    Su, Shi-Lei; Guo, Qi; Wang, Hong-Fu; Zhang, Shou

    2015-08-01

    Inspired by recent work [Carr and Saffman, Phys. Rev. Lett. 111, 033607 (2013), 10.1103/PhysRevLett.111.033607], we propose a simplified scheme to prepare the two-atom maximally entangled states via dissipative Rydberg pumping. Compared with the former scheme, the simplified one involves fewer classical laser fields and Rydberg interactions, and the asymmetric Rydberg interactions are avoided. Master equation simulations demonstrate that the fidelity and the Clauser-Horne-Shimony-Holt correlation of the maximally entangled state could reach up to 0.999 and 2.821, respectively, under certain conditions. Furthermore, we extend the physical thoughts to prepare the three-dimensional entangled state, and the numerical simulations show that, in theory, both the fidelity and the negativity of the desired entanglement could be very close to unity under certain conditions.

  7. Simplified Solutions for Activity Deposited on Moving Filter Media.

    PubMed

    Smith, David L; Chabot, George E

    2016-10-01

    Simplified numerical solutions for particulate activity viewed on moving filter continuous air monitors are developed. The monitor configurations include both rectangular window (RW) and circular window (CW) types. The solutions are demonstrated first for a set of basic airborne radioactivity cases, for a series of concentration pulses, and for indicating the effects of step changes in reactor coolant system (RCS) leakage for a pressurized water reactor. The method is also compared to cases from the prior art. These simplified solutions have additional benefits: They are easily adaptable to multiple radionuclides, they will accommodate collection and detection efficiencies that vary in known ways across the collection area, and they also ease the solution programming. PMID:27575345

  8. Simplified Building Models Extraction from Ultra-Light Uav Imagery

    NASA Astrophysics Data System (ADS)

    Küng, O.; Strecha, C.; Fua, P.; Gurdan, D.; Achtelik, M.; Doth, K.-M.; Stumpf, J.

    2011-09-01

    Generating detailed simplified building models such as the ones present on Google Earth is often a difficult and lengthy manual task, requiring advanced CAD software and a combination of ground imagery, LIDAR data and blueprints. Nowadays, UAVs such as the AscTec Falcon 8 have reached the maturity to offer an affordable, fast and easy way to capture large amounts of oblique images covering all parts of a building. In this paper we present a state-of-the-art photogrammetry and visual reconstruction pipeline provided by Pix4D applied to medium resolution imagery acquired by such UAVs. The key element of simplified building models extraction is the seamless integration of the outputs of such a pipeline for a final manual refinement step in order to minimize the amount of manual work.

  9. A new class of simplified phorbol ester analogues: synthesis and binding to PKC and eta PKC-C1B (eta PKC-CRD2).

    PubMed

    Wender, P A; Kirschberg, T A; Williams, P D; Bastiaans, H M; Irie, K

    1999-10-01

    [formula: see text] A unique class of simplified phorbol ester analogues is described for the first time. A highly efficient retro-annelation sequence was developed in order to remove the five-membered ring from the phorbol diterpene core, allowing access to BCD ring analogues of the phorbol esters. The binding of these analogues to protein kinase C (PKC) and the truncated peptide eta PKC-C1B (eta PKC-CRD2) is also reported. PMID:10825954

  10. Dark matter phenomenology of GUT inspired simplified models

    NASA Astrophysics Data System (ADS)

    Arcadi, Giorgio

    2016-05-01

    We discuss some aspects of dark matter phenomenology, in particular related to Direct detection and collider searches, of models in which a fermionic Dark Matter interacts with SM fermions through spin 1 mediators. Contrary to conventional simplified models we will consider fixed assignments of the couplings of the (Z' ) mediator, according theoretically motivated embeddings. This allows to predict signals at future experimental facilities which can be used to test and possibly discriminate different realizations.

  11. Simplifying the writing process for the novice writer.

    PubMed

    Redmond, Mary Connie

    2002-10-01

    Nurses take responsibility for reading information to update their professional knowledge and to meet relicensure requirements. However, nurses are less enthusiastic about writing for professional publication. This article explores the reluctance of nurses to write, the reasons why writing for publication is important to the nursing profession, the importance of mentoring to potential writers, and basic information about simplifying the writing process for novice writers. PMID:12384898

  12. The pentabox Master Integrals with the Simplified Differential Equations approach

    NASA Astrophysics Data System (ADS)

    Papadopoulos, Costas G.; Tommasini, Damiano; Wever, Christopher

    2016-04-01

    We present the calculation of massless two-loop Master Integrals relevant to five-point amplitudes with one off-shell external leg and derive the complete set of planar Master Integrals with five on-mass-shell legs, that contribute to many 2 → 3 amplitudes of interest at the LHC, as for instance three jet production, γ , V, H + 2 jets etc., based on the Simplified Differential Equations approach.

  13. Simplified renormalizable T' model for tribimaximal mixing and Cabibbo angle

    NASA Astrophysics Data System (ADS)

    Frampton, Paul H.; Kephart, Thomas W.; Matsuzaki, Shinya

    2008-10-01

    In a simplified renormalizable model where the neutrinos have Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixings tan⁡2θ12=(1)/(2), θ13=0, θ23=π/4 and with flavor symmetry T' there is a corresponding prediction where the quarks have Cabibbo-Kobayashi-Maskawa (CKM) mixings tan⁡2Θ12=(2)/(3), Θ13=0, Θ23=0.

  14. Velocity profiles in a hot jet by simplified RELIEF

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Raman Excitation + Laser Induced Electronic Fluorescence (RELIEF) is a double resonance velocimetry technique in which oxygen molecules are vibrationally excited via stimulated Raman scattering at a specific location within a flow field. After suitable time delay, typically 1-10 microseconds, the displacement of the tagged molecules is determined by laser induced fluorescence imaging. Providing support for the installation of simplified RELIEF flow tagging instrumentation at NASA LaRC was the principal goal of this research.

  15. Banded transformer cores

    NASA Technical Reports Server (NTRS)

    Mclyman, C. W. T. (Inventor)

    1974-01-01

    A banded transformer core formed by positioning a pair of mated, similar core halves on a supporting pedestal. The core halves are encircled with a strap, selectively applying tension whereby a compressive force is applied to the core edge for reducing the innate air gap. A dc magnetic field is employed in supporting the core halves during initial phases of the banding operation, while an ac magnetic field subsequently is employed for detecting dimension changes occurring in the air gaps as tension is applied to the strap.

  16. Development of Simplified Atmospheric-Pressure Plasma Nitriding

    NASA Astrophysics Data System (ADS)

    Yamamoto, Hirofumi; Ichiki, Ryuta; Maeda, Akihide; Yamanouchi, Kenta; Akamine, Shuichi; Kanazawa, Seiji; Oita University Team

    2015-09-01

    Nitriding treatment is one of the surface hardening technologies, applied to dies and automobile components. In recent industry, low-pressure nitriding treatment using vacuum system is mainstream. On the other hand, we have originally developed an atmospheric-pressure plasma nitriding which do not need vacuum system. However we needed an air-tight container to purge residual oxygen and external heater to control treatment temperature. To make this technique practical, we addressed to construct a simplified treatment system, where treatment temperature is controlled by thermal plasma itself and oxygen purging is achieved by a simple cover. This means that any air-tight container and external heater is not necessary. As a result, surface temperature is controlled by changing treatment gap from nozzle tip to steel surface. We succeeded in controlling well thickness of hardened layer by adjusting treatment temperature even in such a simplified system. In the conference, we also discuss experimental results for hardening complex shaped materials by using our simplified nitriding.

  17. A simplified technique of performing splenorenal shunt (Omar's technique).

    PubMed

    Shah, Omar Javed; Robbani, Irfan

    2005-01-01

    The splenorenal shunt procedure introduced by Robert Linton in 1947 is still used today in those regions of the world where portal hypertension is a common problem. However, because most surgeons find Linton's shunt procedure technically difficult, we felt that a simpler technique was needed. We present the surgical details and results of 20 splenorenal anastomosis procedures performed within a period of 30 months. Half of the patients (Group I) underwent Linton's conventional technique of splenorenal shunt; the other half (Group II) underwent a newly devised, simplified shunt technique. This new technique involves dissection of the fusion fascia of Toldt. The outcome of the 2 techniques was identical with respect to the reduction of preshunt portal pressure. However, our simplified technique was advantageous in that it significantly reduced the duration of surgery (P <0.001) and the amount of intraoperative blood loss (P <0.003). No patient died after either operation. Although Linton's splenorenal shunt is difficult and technically demanding, it is still routinely performed. The new technique described here, in addition to being simpler, helps achieve good vascular control, permits easier dissection of the splenic vein, enables an ideal anastomosis, decreases intraoperative blood loss, and reduces the duration of surgery. Therefore, we recommend the routine use of this simplified technique (Omar's technique) for the surgical treatment of portal hypertension. PMID:16429901

  18. Simplified cyclic structural analyses of SSME turbine blades

    NASA Technical Reports Server (NTRS)

    Kaufman, A.; Manderscheid, J. M.

    1986-01-01

    Anisotropic high-temperature alloys are used to meet the safety and durability requirements of turbine blades for high-pressure turbopumps in reusable space propulsion systems. The applicability to anisotropic components of a simplified inelastic structural analysis procedure developed at the NASA Lewis Research Center is assessed. The procedure uses as input the history of the total strain at the critical crack initiation location computed from elastic finite-element analyses. Cyclic heat transfer and structural analyses are performed for the first stage high-pressure fuel turbopump blade of the space shuttle main engine. The blade alloy is directionally solidified MAR-M 246 (nickel base). The analyses are based on a typical test stand engine cycle. Stress-strain histories for the airfoil critical location are computed using both the MARC nonlinear finite-element computer code and the simplified procedure. Additional cases are analyzed in which the material yield strength is arbitrarily reduced to increase the plastic strains and, therefore, the severity of the problem. Good agreement is shown between the predicted stress-strain solutions from the two methods. The simplified analysis uses about 0.02 percent (5 percent with the required elastic finite-element analyses) of the CPU time used by the nonlinear finite element analysis.

  19. Simplified tornado depressurization design methods for nuclear power plants

    SciTech Connect

    Howard, N.M.; Krasnopoler, M.I.

    1983-05-01

    A simplified approach for the calculation of tornado depressurization effects on nuclear power plant structures and components is based on a generic computer depressurization analysis for an arbitrary single volume V connected to the atmosphere by an effective vent area A. For a given tornado depressurization transient, the maximum depressurization ..delta..P of the volume was found to depend on the parameter V/A. The relation between ..delta..P and V/A can be represented by a single monotonically increasing curve for each of the three design-basis tornadoes described in the U.S. Nuclear Regulatory Commission's Regulatory Guide 1.76. These curves can be applied to most multiple-volume nuclear power plant structures by considering each volume and its controlling vent area. Where several possible flow areas could be controlling, the maximum value of V/A can be used to estimate a conservative value for ..delta..P. This simplified approach was shown to yield reasonably conservative results when compared to detailed computer calculations of moderately complex geometries. Treatment of severely complicated geometries, heating and ventilation systems, and multiple blowout panel arrangements were found to be beyond the limitations of the simplified analysis.

  20. Effects of core barrel on vessel seismic loadings. [LMFBR

    SciTech Connect

    Ma, D.C.; Gvildys, J.; Chang, Y.W.

    1983-01-01

    Reliability of reactor systems under seismic events is a major concern for the safety of the nuclear power plants. This paper deals with the effects of the core barrel on the seismic response of reactor tanks. The main emphases are the effects of core barrel on the free-surface wave height and the fluid coupling effects between the core barrel and primary tank. This study represents an initial step to investigate the effects of in-tank components, structures on the seismically-induced hydrodynamic behavior of the reactor tanks. To simplify the analysis, the tank used in the study is simulated by a two-dimensional model. Two parametric studies were carried out in which the wall flexibility and location of core barrel were used as parameters respectively.

  1. "Snowing" Core in Earth?

    NASA Astrophysics Data System (ADS)

    Li, J.; Chen, B.; Cormier, V.; Gao, L.; Gubbins, D.; Kharlamova, S. A.; He, K.; Yang, H.

    2008-12-01

    As a planet cools, an initially molten core gradually solidifies. Solidification occurs at shallow depths in the form of "snow", if the liquidus temperature gradient of the core composition is smaller than the adiabatic temperature gradient in the core. Experimental data on the melting behavior of iron-sulfur binary system suggest that the cores of Mercury and Ganymede are probably snowing at the present time. The Martian core is predicted to snow in the future, provided that the sulfur content falls into the range of 10 to 14 weight percent. Is the Earth's core snowing? If so, what are the surface manifestations? If the Earth's core snowed in the past, how did it affect the formation of the solid inner core and the geodynamo? Here, we evaluate the likelihood and consequences of a snowing core throughout the Earth's history, on the basis of mineral physics data describing the melting behavior, equation-of-state, and thermodynamic properties of iron-rich alloys at high pressures. We discuss if snowing in the present-day Earth can reproduce the shallow gradients of compressional wave velocity above the inner-core boundary, and whether or not snowing in the early Earth may reconcile the apparent young age of the solid inner core with a long-lived geodynamo.

  2. Continuous coring drill bit

    SciTech Connect

    Ford, G.A.

    1987-09-22

    A continuous coring drill bit is described comprising: (a) body means defining a vertical axis and adapted for connection to drill pipe and forming an internal body cavity disposed in eccentric relation with the vertical axis and a generally circular throat in communication with the body cavity for conducting drilling fluid. The throat defining a throat axis coincident with the vertical axis and being of a configuration permitting passage of a formation core into the body cavity; (b) a generally cylindrical tubular core breaker being rotatably mounted within the body cavity and defining a vertical axis of rotation of generally parallel and offset relation with the vertical axis of the body means; and (c) a buttress element extending inwardly from the core breaker and adapted to contact the formation core. Upon each rotation of the drill bit the buttress element applying transverse force to the core for fracturing of the core into sections sufficiently small for transport by the drilling fluid.

  3. HYDRATE CORE DRILLING TESTS

    SciTech Connect

    John H. Cohen; Thomas E. Williams; Ali G. Kadaster; Bill V. Liddell

    2002-11-01

    The ''Methane Hydrate Production from Alaskan Permafrost'' project is a three-year endeavor being conducted by Maurer Technology Inc. (MTI), Noble, and Anadarko Petroleum, in partnership with the U.S. DOE National Energy Technology Laboratory (NETL). The project's goal is to build on previous and ongoing R&D in the area of onshore hydrate deposition. The project team plans to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope includes drilling and coring one well on Anadarko leases in FY 2003 during the winter drilling season. A specially built on-site core analysis laboratory will be used to determine some of the physical characteristics of the hydrates and surrounding rock. Prior to going to the field, the project team designed and conducted a controlled series of coring tests for simulating coring of hydrate formations. A variety of equipment and procedures were tested and modified to develop a practical solution for this special application. This Topical Report summarizes these coring tests. A special facility was designed and installed at MTI's Drilling Research Center (DRC) in Houston and used to conduct coring tests. Equipment and procedures were tested by cutting cores from frozen mixtures of sand and water supported by casing and designed to simulate hydrate formations. Tests were conducted with chilled drilling fluids. Tests showed that frozen core can be washed out and reduced in size by the action of the drilling fluid. Washing of the core by the drilling fluid caused a reduction in core diameter, making core recovery very difficult (if not impossible). One successful solution was to drill the last 6 inches of core dry (without fluid circulation). These tests demonstrated that it will be difficult to capture core when drilling in permafrost or hydrates without implementing certain safeguards. Among the coring tests was a simulated hydrate formation comprised of coarse, large

  4. 23. CORE WORKER OPERATING A COREBLOWER THAT PNEUMATICALLY FILLED CORE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. CORE WORKER OPERATING A CORE-BLOWER THAT PNEUMATICALLY FILLED CORE BOXES WITH RESIGN IMPREGNATED SAND AND CREATED A CORE THAT THEN REQUIRED BAKING, CA. 1950. - Stockham Pipe & Fittings Company, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  5. Core-Cutoff Tool

    NASA Technical Reports Server (NTRS)

    Gheen, Darrell

    2007-01-01

    A tool makes a cut perpendicular to the cylindrical axis of a core hole at a predetermined depth to free the core at that depth. The tool does not damage the surrounding material from which the core was cut, and it operates within the core-hole kerf. Coring usually begins with use of a hole saw or a hollow cylindrical abrasive cutting tool to make an annular hole that leaves the core (sometimes called the plug ) in place. In this approach to coring as practiced heretofore, the core is removed forcibly in a manner chosen to shear the core, preferably at or near the greatest depth of the core hole. Unfortunately, such forcible removal often damages both the core and the surrounding material (see Figure 1). In an alternative prior approach, especially applicable to toxic or fragile material, a core is formed and freed by means of milling operations that generate much material waste. In contrast, the present tool eliminates the damage associated with the hole-saw approach and reduces the extent of milling operations (and, hence, reduces the waste) associated with the milling approach. The present tool (see Figure 2) includes an inner sleeve and an outer sleeve and resembles the hollow cylindrical tool used to cut the core hole. The sleeves are thin enough that this tool fits within the kerf of the core hole. The inner sleeve is attached to a shaft that, in turn, can be attached to a drill motor or handle for turning the tool. This tool also includes a cutting wire attached to the distal ends of both sleeves. The cutting wire is long enough that with sufficient relative rotation of the inner and outer sleeves, the wire can cut all the way to the center of the core. The tool is inserted in the kerf until its distal end is seated at the full depth. The inner sleeve is then turned. During turning, frictional drag on the outer core pulls the cutting wire into contact with the core. The cutting force of the wire against the core increases with the tension in the wire and

  6. Lunar core: occam's razor?

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    Whether or not the earth's moon has a core is a much bandied question. Like many notions about the properties of the moon, ideas of a lunar core changed drastically after the Apollo studies. A review of the development of these ideas was given a scholarly treatment by S.K. Runcorn recently (Nature, 304, 589-596, 1983). In contrast, L.L. Hood, C.P. Sonett, and L.J. Srnka have questioned the concept in serious detail (Nature, 307, 661-662, 1984).Whether or not the moon actually has or has had a fluid metallic core is of great consequence for a number of geophysical theories about the solar system. Most investigators concede that the possible existence of a lunar core remains one of the major unanswered, and yet most critical, questions about the moon. A lot rides on the answer: Can a lunar-sized body have a core? Is the core metallic? How is the core related to lunar magnetism and its paleomagnetism? Is or was a lunar core related to lunar volcanism? If the moon can have a core, is planetary core formation in the solar system a simple matter of gravitationally segregating metallic fragments that were formed elsewhere? Implications of the questions are without limit. There is, perhaps, no more valid issue about the moon to explore scientifically.

  7. Core sample extractor

    NASA Technical Reports Server (NTRS)

    Akins, James; Cobb, Billy; Hart, Steve; Leaptrotte, Jeff; Milhollin, James; Pernik, Mark

    1989-01-01

    The problem of retrieving and storing core samples from a hole drilled on the lunar surface is addressed. The total depth of the hole in question is 50 meters with a maximum diameter of 100 millimeters. The core sample itself has a diameter of 60 millimeters and will be two meters in length. It is therefore necessary to retrieve and store 25 core samples per hole. The design utilizes a control system that will stop the mechanism at a certain depth, a cam-linkage system that will fracture the core, and a storage system that will save and catalogue the cores to be extracted. The Rod Changer and Storage Design Group will provide the necessary tooling to get into the hole as well as to the core. The mechanical design for the cam-linkage system as well as the conceptual design of the storage device are described.

  8. The core paradox.

    NASA Technical Reports Server (NTRS)

    Kennedy, G. C.; Higgins, G. H.

    1973-01-01

    Rebuttal of suggestions from various critics attempting to provide an escape from the seeming paradox originated by Higgins and Kennedy's (1971) proposed possibility that the liquid in the outer core was thermally stably stratified and that this stratification might prove a powerful inhibitor to circulation of the outer core fluid of the kind postulated for the generation of the earth's magnetic field. These suggestions are examined and shown to provide no reasonable escape from the core paradox.

  9. AN Core Analysis

    NASA Astrophysics Data System (ADS)

    Barbarino, Andrea; Tomatis, Daniele

    2014-06-01

    Several alternative approximations of neutron transport have been proposed in years to move around the known limitations imposed by neutron diffusion in the modeling of nuclear cores. However, only a few complied with the industrial requirements of fast numerical computation, concentrating more on physical accuracy. In this work, the AN transport methodology is discussed with particular interest in core performance calculations. The implementation of the methodology in full core codes is discussed with particular attention to numerical issues and to the integration within the entire simulation process. Finally, first results from core studies in AN transport are analyzed in detail and compared to standard results of neutron diffusion.

  10. Helicopter engine core noise

    NASA Astrophysics Data System (ADS)

    Vonglahn, U. H.

    1982-07-01

    Calculated engine core noise levels, based on NASA Lewis prediction procedures, for five representative helicopter engines are compared with measured total helicopter noise levels and ICAO helicopter noise certification requirements. Comparisons are made for level flyover and approach procedures. The measured noise levels are generally significantly greater than those predicted for the core noise levels, except for the Sikorsky S-61 and S-64 helicopters. However, the predicted engine core noise levels are generally at or within 3 dB of the ICAO noise rules. Consequently, helicopter engine core noise can be a significant contributor to the overall helicopter noise signature.

  11. Helicopter engine core noise

    NASA Technical Reports Server (NTRS)

    Vonglahn, U. H.

    1982-01-01

    Calculated engine core noise levels, based on NASA Lewis prediction procedures, for five representative helicopter engines are compared with measured total helicopter noise levels and ICAO helicopter noise certification requirements. Comparisons are made for level flyover and approach procedures. The measured noise levels are generally significantly greater than those predicted for the core noise levels, except for the Sikorsky S-61 and S-64 helicopters. However, the predicted engine core noise levels are generally at or within 3 dB of the ICAO noise rules. Consequently, helicopter engine core noise can be a significant contributor to the overall helicopter noise signature.

  12. Core Research Center

    USGS Publications Warehouse

    Hicks, Joshua; Adrian, Betty

    2009-01-01

    The Core Research Center (CRC) of the U.S. Geological Survey (USGS), located at the Denver Federal Center in Lakewood, Colo., currently houses rock core from more than 8,500 boreholes representing about 1.7 million feet of rock core from 35 States and cuttings from 54,000 boreholes representing 238 million feet of drilling in 28 States. Although most of the boreholes are located in the Rocky Mountain region, the geologic and geographic diversity of samples have helped the CRC become one of the largest and most heavily used public core repositories in the United States. Many of the boreholes represented in the collection were drilled for energy and mineral exploration, and many of the cores and cuttings were donated to the CRC by private companies in these industries. Some cores and cuttings were collected by the USGS along with other government agencies. Approximately one-half of the cores are slabbed and photographed. More than 18,000 thin sections and a large volume of analytical data from the cores and cuttings are also accessible. A growing collection of digital images of the cores are also becoming available on the CRC Web site Internet http://geology.cr.usgs.gov/crc/.

  13. Health Information in Chinese - Simplified (简体中文): MedlinePlus

    MedlinePlus

    ... Bilingual PDF Health Information Translations Appendectomy for a Child 儿童阑尾切除术 - 简体中文 (Chinese - Simplified) Bilingual PDF Health Information ... Simplified) Bilingual PDF Health Information Translations Asthma in Children Nebulizer Treatments 喷雾器治疗 - 简体中文 (Chinese - Simplified) Bilingual PDF ...

  14. A Simplified Model of Choice Behavior under Uncertainty

    PubMed Central

    Lin, Ching-Hung; Lin, Yu-Kai; Song, Tzu-Jiun; Huang, Jong-Tsun; Chiu, Yao-Chu

    2016-01-01

    The Iowa Gambling Task (IGT) has been standardized as a clinical assessment tool (Bechara, 2007). Nonetheless, numerous research groups have attempted to modify IGT models to optimize parameters for predicting the choice behavior of normal controls and patients. A decade ago, most researchers considered the expected utility (EU) model (Busemeyer and Stout, 2002) to be the optimal model for predicting choice behavior under uncertainty. However, in recent years, studies have demonstrated that models with the prospect utility (PU) function are more effective than the EU models in the IGT (Ahn et al., 2008). Nevertheless, after some preliminary tests based on our behavioral dataset and modeling, it was determined that the Ahn et al. (2008) PU model is not optimal due to some incompatible results. This study aims to modify the Ahn et al. (2008) PU model to a simplified model and used the IGT performance of 145 subjects as the benchmark data for comparison. In our simplified PU model, the best goodness-of-fit was found mostly as the value of α approached zero. More specifically, we retested the key parameters α, λ, and A in the PU model. Notably, the influence of the parameters α, λ, and A has a hierarchical power structure in terms of manipulating the goodness-of-fit in the PU model. Additionally, we found that the parameters λ and A may be ineffective when the parameter α is close to zero in the PU model. The present simplified model demonstrated that decision makers mostly adopted the strategy of gain-stay loss-shift rather than foreseeing the long-term outcome. However, there are other behavioral variables that are not well revealed under these dynamic-uncertainty situations. Therefore, the optimal behavioral models may not have been found yet. In short, the best model for predicting choice behavior under dynamic-uncertainty situations should be further evaluated. PMID:27582715

  15. A Simplified Model of Choice Behavior under Uncertainty.

    PubMed

    Lin, Ching-Hung; Lin, Yu-Kai; Song, Tzu-Jiun; Huang, Jong-Tsun; Chiu, Yao-Chu

    2016-01-01

    The Iowa Gambling Task (IGT) has been standardized as a clinical assessment tool (Bechara, 2007). Nonetheless, numerous research groups have attempted to modify IGT models to optimize parameters for predicting the choice behavior of normal controls and patients. A decade ago, most researchers considered the expected utility (EU) model (Busemeyer and Stout, 2002) to be the optimal model for predicting choice behavior under uncertainty. However, in recent years, studies have demonstrated that models with the prospect utility (PU) function are more effective than the EU models in the IGT (Ahn et al., 2008). Nevertheless, after some preliminary tests based on our behavioral dataset and modeling, it was determined that the Ahn et al. (2008) PU model is not optimal due to some incompatible results. This study aims to modify the Ahn et al. (2008) PU model to a simplified model and used the IGT performance of 145 subjects as the benchmark data for comparison. In our simplified PU model, the best goodness-of-fit was found mostly as the value of α approached zero. More specifically, we retested the key parameters α, λ, and A in the PU model. Notably, the influence of the parameters α, λ, and A has a hierarchical power structure in terms of manipulating the goodness-of-fit in the PU model. Additionally, we found that the parameters λ and A may be ineffective when the parameter α is close to zero in the PU model. The present simplified model demonstrated that decision makers mostly adopted the strategy of gain-stay loss-shift rather than foreseeing the long-term outcome. However, there are other behavioral variables that are not well revealed under these dynamic-uncertainty situations. Therefore, the optimal behavioral models may not have been found yet. In short, the best model for predicting choice behavior under dynamic-uncertainty situations should be further evaluated. PMID:27582715

  16. Simplified dead-time compensator for multiple delay SISO systems.

    PubMed

    Torrico, Bismark Claure; Correia, Wilkley Bezerra; Nogueira, Fabrício Gonzalez

    2016-01-01

    This paper presents a dead-time compensation structure able to deal with stable and unstable multiple delay single input single output (SISO) systems. The proposed method aims to simplify the primary controller by replacing it for FIR filters placed at the feedback path. Such modification reduces the total number of parameters to be tuned which facilitates the overall design in comparison with other primary controllers normally considered. Simulation results show a better performance for the proposed control approach compared with other dead-time compensator (DTC) recently proposed in the literature. PMID:26593966

  17. A simplified approach to calibrating [sup 14]C dates

    SciTech Connect

    Talma, A.S.; Vogel, J.C. )

    1993-01-01

    The authors propose a simplified approach to the calibration of radiocarbon dates. They use splines through the tree-ring data as calibration curves, thereby eliminating a large part of the statistical scatter of the actual data points. To express the age range, they transform the [plus minus]1 [sigma] and [plus minus]2 [sigma] values of the BP age to calendar dates and interpret them as the 68% and 95% confidence intervals. This approach by-passes the conceptual problems of the transfer of individual probability values from the radiocarbon to the calendar age. They have adapted software to make this calibration possible.

  18. Simplified fatigue life analysis for traction drive contacts

    NASA Technical Reports Server (NTRS)

    Rohn, D. A.; Loewenthal, S. H.; Coy, J. J.

    1980-01-01

    A simplified fatigue life analysis for traction drive contacts of arbitrary geometry is presented. The analysis is based on the Lundberg-Palmgren theory used for rolling-element bearings. The effects of torque, element size, speed, contact ellipse ratio, and the influence of traction coefficient are shown. The analysis shows that within the limits of the available traction coefficient, traction contacts exhibit longest life at high speeds. Multiple, load-sharing roller arrangements have an advantageous effect on system life, torque capacity, power-to-weight ratio and size.

  19. A simplified method for extracting androgens from avian egg yolks

    USGS Publications Warehouse

    Kozlowski, C.P.; Bauman, J.E.; Hahn, D.C.

    2009-01-01

    Female birds deposit significant amounts of steroid hormones into the yolks of their eggs. Studies have demonstrated that these hormones, particularly androgens, affect nestling growth and development. In order to measure androgen concentrations in avian egg yolks, most authors follow the extraction methods outlined by Schwabl (1993. Proc. Nat. Acad. Sci. USA 90:11446-11450). We describe a simplified method for extracting androgens from avian egg yolks. Our method, which has been validated through recovery and linearity experiments, consists of a single ethanol precipitation that produces substantially higher recoveries than those reported by Schwabl.

  20. Simplified Exactly Solvable Model for β-Amyloid Aggregation

    NASA Astrophysics Data System (ADS)

    Zamparo, M.; Trovato, A.; Maritan, A.

    2010-09-01

    We propose an exactly solvable simplified statistical mechanical model for the thermodynamics of β-amyloid aggregation, generalizing a well-studied model for protein folding. The monomer concentration is explicitly taken into account as well as a nontrivial dependence on the microscopic degrees of freedom of the single peptide chain, both in the α-helix folded isolated state and in the fibrillar one. The phase diagram of the model is studied and compared to the outcome of fibril formation experiments which is qualitatively reproduced.

  1. Simplified design procedures for fiber composite structural components/joints

    NASA Technical Reports Server (NTRS)

    Murthy, P. L. N.; Chamis, Christos C.

    1990-01-01

    Simplified step-by-step design procedures are summarized, which are suitable for the preliminary design of composite structural components such as panels (laminates) and composite built-up structures (box beams). Similar procedures are also summarized for the preliminary design of composite bolted and adhesively bonded joints. The summary is presented in terms of sample design cases complemented with typical results. Guidelines are provided which can be used in the design selection process of composite structural components/joints. Also, procedures to account for cyclic loads, hygrothermal effects and lamination residual stresses are included.

  2. A simplified biosphere model for global climate studies

    NASA Technical Reports Server (NTRS)

    Xue, Y.; Sellers, P. J.; Kinter, J. L.; Shukla, J.

    1991-01-01

    A comprehensive analysis of the simple biosphere model (SIB) of Sellers et al. (1986) is performed in an effort to bridge the gap between the typical hydrological treatment of the land surface biosphere and the conventional general circulation model treatment, which is specified through a single parameter. Approximations are developed that stimulate the effects of reduced soil moisture more simply, maintaining the essence of the biophysical concepts utilized in SIB. Comparing the reduced parameter biosphere with those from the original formulation in a GCM and a zero-dimensional model shows the simplified version to reproduce the original results quite closely.

  3. ESPRESSO APSU: simplify the life of pupil slicing

    NASA Astrophysics Data System (ADS)

    Conconi, P.; Riva, M.; Pepe, F.; Zerbi, F. M.; Cabral, A.; Cristiani, S.; Megevand, D.; Landoni, M.; Spanó, P.

    2013-09-01

    This paper presents the Espresso Anamorphic pupil Slicer (APSU) implementation. ESPRESSO, the Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations, will be installed on ESOs Very Large Telescope (VLT). In this work we will present the design and trade-off for the pupil slicing system introduced in order to increase the resolving power, effectively decreasing slit width. Its based onto simplified optical component that introduce large anamorphism while keeping low aberrations by means of cylindrical optics. We describe here the trade-off between slicing through two adjacent squared doublets and two achromatic prisms.

  4. On mono-W signatures in spin-1 simplified models

    NASA Astrophysics Data System (ADS)

    Haisch, Ulrich; Kahlhoefer, Felix; Tait, Tim M. P.

    2016-09-01

    The potential sensitivity to isospin-breaking effects makes LHC searches for mono-W signatures promising probes of the coupling structure between the Standard Model and dark matter. It has been shown, however, that the strong sensitivity of the mono-W channel to the relative magnitude and sign of the up-type and down-type quark couplings to dark matter is an artifact of unitarity violation. We provide three different solutions to this mono-W problem in the context of spin-1 simplified models and briefly discuss the impact that our findings have on the prospects of mono-W searches at future LHC runs.

  5. A VLSI architecture for simplified arithmetic Fourier transform algorithm

    NASA Technical Reports Server (NTRS)

    Reed, Irving S.; Shih, Ming-Tang; Truong, T. K.; Hendon, E.; Tufts, D. W.

    1992-01-01

    The arithmetic Fourier transform (AFT) is a number-theoretic approach to Fourier analysis which has been shown to perform competitively with the classical FFT in terms of accuracy, complexity, and speed. Theorems developed in a previous paper for the AFT algorithm are used here to derive the original AFT algorithm which Bruns found in 1903. This is shown to yield an algorithm of less complexity and of improved performance over certain recent AFT algorithms. A VLSI architecture is suggested for this simplified AFT algorithm. This architecture uses a butterfly structure which reduces the number of additions by 25 percent of that used in the direct method.

  6. Some theoretical and computational aspects of a simplified subchannel model

    SciTech Connect

    Neil, C.H.

    1983-01-01

    Some recently obtained results are presented concerning the qualitative behavior of solutions to equations governing a simplified subchannel model for reactor hydrodynamics. The model describes time-independent flow of an incompressible fluid in two parallel, interconnected channels, subject to axial and lateral pressure drops defined by a Darcy friction factor. The phase portrait for the system of ordinary differential equations is presented, a solution to a boundary-value problem describing flow blockage is discussed, and the effect of the qualitative behavior of solutions on their numerical approximation is examined. The study was undertaken to determine the cause of numerical difficulty in approximating solutions to problems.

  7. Simplifying clinical use of the genetic risk prediction model BRCAPRO.

    PubMed

    Biswas, Swati; Atienza, Philamer; Chipman, Jonathan; Hughes, Kevin; Barrera, Angelica M Gutierrez; Amos, Christopher I; Arun, Banu; Parmigiani, Giovanni

    2013-06-01

    Health care providers need simple tools to identify patients at genetic risk of breast and ovarian cancers. Genetic risk prediction models such as BRCAPRO could fill this gap if incorporated into Electronic Medical Records or other Health Information Technology solutions. However, BRCAPRO requires potentially extensive information on the counselee and her family history. Thus, it may be useful to provide simplified version(s) of BRCAPRO for use in settings that do not require exhaustive genetic counseling. We explore four simplified versions of BRCAPRO, each using less complete information than the original model. BRCAPROLYTE uses information on affected relatives only up to second degree. It is in clinical use but has not been evaluated. BRCAPROLYTE-Plus extends BRCAPROLYTE by imputing the ages of unaffected relatives. BRCAPROLYTE-Simple reduces the data collection burden associated with BRCAPROLYTE and BRCAPROLYTE-Plus by not collecting the family structure. BRCAPRO-1Degree only uses first-degree affected relatives. We use data on 2,713 individuals from seven sites of the Cancer Genetics Network and MD Anderson Cancer Center to compare these simplified tools with the Family History Assessment Tool (FHAT) and BRCAPRO, with the latter serving as the benchmark. BRCAPROLYTE retains high discrimination; however, because it ignores information on unaffected relatives, it overestimates carrier probabilities. BRCAPROLYTE-Plus and BRCAPROLYTE-Simple provide better calibration than BRCAPROLYTE, so they have higher specificity for similar values of sensitivity. BRCAPROLYTE-Plus performs slightly better than BRCAPROLYTE-Simple. The Areas Under the ROC curve are 0.783 (BRCAPRO), 0.763 (BRCAPROLYTE), 0.772 (BRCAPROLYTE-Plus), 0.773 (BRCAPROLYTE-Simple), 0.728 (BRCAPRO-1Degree), and 0.745 (FHAT). The simpler versions, especially BRCAPROLYTE-Plus and BRCAPROLYTE-Simple, lead to only modest loss in overall discrimination compared to BRCAPRO in this dataset. Thus, we conclude that

  8. A simplified In Situ cosmogenic 14C extraction system

    USGS Publications Warehouse

    Pigati, J.S.; Lifton, N.A.; Timothy, Jull A.J.; Quade, Jay

    2010-01-01

    We describe the design, construction, and testing of a new, simplified in situ radiocarbon extraction system at the University of Arizona. Blank levels for the new system are low ((234 ?? 11) ?? 103 atoms (1 ??; n = 7)) and stable. The precision of a given measurement depends on the concentration of 14C, but is typically <5% for concentrations of 100 ?? 103 atoms g-1 or more. The new system is relatively small and easy to construct, costs significantly less than the original in situ 14C extraction system at Arizona, and lends itself to future automation. ?? 2010 by the Arizona Board of Regents on behalf of the University of Arizona.

  9. Technology Solutions Case Study: Combustion Safety Simplified Test Protocol

    SciTech Connect

    L. Brand, D. Cautley, D. Bohac, P. Francisco, L. Shen, and S. Gloss

    2015-12-01

    Combustions safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives.

  10. Simulation and simplified design of photovoltaic power systems

    NASA Astrophysics Data System (ADS)

    Evans, D. L.; Facinelli, W. A.; Koehler, L. P.

    Results of TRNSYS simulations of photovoltaic systems with and without battery storage are described. The systems have south facing, flat arrays that are max-power tracked and have one day or less of storage. Studies of the sensitivity of system performance, in terms of the fraction of the electrical load supplied by the solar energy system, to variables such as array size, battery size, location, time of year, and load shape are reported. A simplified method for calculating system performance is described and examples of its accuracy are presented.

  11. Simplified solution for point contact deformation between two elastic solids

    NASA Technical Reports Server (NTRS)

    Brewe, D. E.; Hamrock, B. J.

    1976-01-01

    A linear-regression by the method of least squares is made on the geometric variables that occur in the equation for point contact deformation. The ellipticity and the complete eliptic integrals of the first and second kind are expressed as a function of the x, y-plane principal radii. The ellipticity was varied from 1 (circular contact) to 10 (a configuration approaching line contact). These simplified equations enable one to calculate easily the point-contact deformation to within 3 percent without resorting to charts or numerical methods.

  12. Simplified simulation models for control studies of turbojet engines

    NASA Technical Reports Server (NTRS)

    Brennan, T. C.; Leake, R. J.

    1975-01-01

    The essential dynamical characteristics of a simple single spool turbojet engine were determined through simulation of low order system models on an analog computer. An accurate model was studied and system complexity was reduced through various linearizations and approximations. A derivation of a seventh order simplified simulation model is presented with a derivation of an even simpler third order model, and simulation results from each. The control problem studied is one of getting from zero fuel flow equilibrium to a high thrust equilibrium while taking into account surge margin and turbine inlet temperature constraints.

  13. Simplified quantum bit commitment using single photon nonlocality

    NASA Astrophysics Data System (ADS)

    He, Guang Ping

    2014-10-01

    We simplified our previously proposed quantum bit commitment (QBC) protocol based on the Mach-Zehnder interferometer, by replacing symmetric beam splitters with asymmetric ones. It eliminates the need for random sending time of the photons; thus, the feasibility and efficiency are both improved. The protocol is immune to the cheating strategy in the Mayers-Lo-Chau no-go theorem of unconditionally secure QBC, because the density matrices of the committed states do not satisfy a crucial condition on which the no-go theorem holds.

  14. Simplifying the Measurement of Gastric Accommodation using SPECT

    PubMed Central

    Vijayvargiya, Priya; Camilleri, Michael; Shin, Andrea; Breen, Mary; Burton, Duane

    2013-01-01

    Background Noninvasive single photon emission computed tomography (SPECT) has been validated as a test for postprandial gastric volume accommodation, with volumes measured twice over 30 minutes and averaged. The purpose of this study is to simplify the SPECT measurement of gastric accommodation. Methods The primary aim of this study was to compare 2 postprandial gastric volume measurements with data collected retrospectively from 443 patients and healthy volunteers who had undergone SPECT in the last decade. The differences in the two gastric volumes were compared in the entire group and each subgroup, and the correlation between the 2 measurements and their differences across a wide range of gastric volumes were plotted. Key Results There was a median difference of <2% (p=0.041) between postprandial scan 1 (757 mL) and scan 2 (743 mL), with significant correlation (rs = 0.859, p<0.01) and excellent agreement (S.D. 60 mL) between the 2 scans across the entire range of observed postprandial gastric volumes. Conclusions & Inferences A single postprandial scan can detect gastric accommodation with the same accuracy as averaging 2 postprandial scans. These data support simplifying SPECT measurement of postprandial gastric volume with a scan in the first 15 minutes after a meal. PMID:23413813

  15. A simplified Reynolds stress model for unsteady turbulent boundary layers

    NASA Technical Reports Server (NTRS)

    Fan, Sixin; Lakshminarayana, Budugur

    1993-01-01

    A simplified Reynolds stress model has been developed for the prediction of unsteady turbulent boundary layers. By assuming that the net transport of Reynolds stresses is locally proportional to the net transport of the turbulent kinetic energy, the time dependent full Reynolds stress model is reduced to a set of ordinary differential equations. These equations contain only time derivatives and can be readily integrated in a time dependent boundary layer or Navier-Stokes code. The turbulent kinetic energy and dissipation rate needed for the model are obtained by solving the k-epsilon equations. This simplified Reynolds stress turbulence model (SRSM) does not use the eddy viscosity assumption, which may not be valid for unsteady turbulent flows. The anisotropy of both the steady and the unsteady turbulent normal stresses can be captured by the SRSM model. Through proper damping of the shear stresses, the present model can be used in the near wall region of turbulent boundary layers. This model has been validated against data for steady and unsteady turbulent boundary layers, including periodic turbulent boundary layers subjected to a mean adverse pressure gradient. For the cases tested, the predicted unsteady velocity and turbulent stress components agree well with the experimental data. Comparison between the predictions from the SRSM model and a k-epsilon model is also presented.

  16. Cardiac dynamics: a simplified model for action potential propagation

    PubMed Central

    2012-01-01

    This paper analyzes a new semiphysiological ionic model, used recently to study reexitations and reentry in cardiac tissue [I.R. Cantalapiedra et al, PRE 82 011907 (2010)]. The aim of the model is to reproduce action potencial morphologies and restitution curves obtained, either from experimental data, or from more complex electrophysiological models. The model divides all ion currents into four groups according to their function, thus resulting into fast-slow and inward-outward currents. We show that this simplified model is flexible enough as to accurately capture the electrical properties of cardiac myocytes, having the advantage of being less computational demanding than detailed electrophysiological models. Under some conditions, it has been shown to be amenable to mathematical analysis. The model reproduces the action potential (AP) change with stimulation rate observed both experimentally and in realistic models of healthy human and guinea pig myocytes (TNNP and LRd models, respectively). When simulated in a cable it also gives the right dependence of the conduction velocity (CV) with stimulation rate. Besides reproducing correctly these restitution properties, it also gives a good fit for the morphology of the AP, including the notch typical of phase 1. Finally, we perform simulations in a realistic geometric model of the rabbit’s ventricles, finding a good qualitative agreement in AP propagation and the ECG. Thus, this simplified model represents an alternative to more complex models when studying instabilities in wave propagation. PMID:23194429

  17. Simplifying the ultrasound findings of the major fetal chromosomal aneuploidies.

    PubMed

    Liau, Joy; Romine, Lorene; Korty, Lauren A; Chao, Cherng; White, Katherine; Harmon, Sheena; Ho, Yoona; Hull, Andrew D; Pretorius, Dolores H

    2014-01-01

    Sonographic aneuploidy markers and structural anomalies associated with the 5 most common chromosomal aneuploidies are organized and simplified to highlight the many sonographic findings that are commonly seen with each aneuploidy. Identification of these findings allows families to have the option to pursue prenatal genetic testing to confirm or exclude chromosomal abnormalities suggested by such prenatal ultrasound findings and make informed decisions about the subsequent management of their pregnancy. We review the most common major human chromosomal aneuploidies, including trisomies 21, 18, and 13; Turner syndrome; and triploidy. The focus is on the major structural anomalies seen with each of these, as well as ultrasound markers (findings associated with increased risk of chromosomal abnormality but also seen in normal fetuses). The role of clinical information such as maternal serum screening and new cell-free fetal DNA screening is also reviewed. As patients do not usually present for fetal ultrasound with a known diagnosis, a concise knowledge of ultrasound and clinical findings will alert radiologists to concerning cases and prompt a guided search for important associated anomalies. Fetal ultrasound can be challenging owing to the many findings and sometimes technically difficult evaluation. By simplifying the ultrasound findings seen with the major chromosomal abnormalities and highlighting the role of clinical history, we hope that an informed search for specific sonographic findings can be performed; thereby, reducing missed diagnoses. PMID:25239075

  18. Nonlinear dynamics of a simplified engine-propeller system

    NASA Astrophysics Data System (ADS)

    Yu, S. D.; Warwick, S. A.; Zhang, X.

    2009-07-01

    This paper presents a procedure for studying dynamical behaviors of a simplified engine-propeller dynamical system consisting of a number of bodies of plane motions. The equation of motion of the complex system is obtained using the Lagrange equation and solved numerically using the 4th order Runge-Kutta method. Various simulations were performed to investigate the transient and steady state behaviors of the multiple body system while taking into consideration the engine pressure pulsations, nonlinear inertia of moving bodies, and nonlinear aerodynamic load. Sub-harmonics and super harmonics in the steady state responses for different power and propeller pitch settings are obtained using the fast Fourier transform. Numerical simulations indicate that the 1.5 order is the dominant order of harmonics in the steady state oscillatory motion of the crankshaft. The findings and procedure presented in the paper are useful to the aerospace industry in certifying reciprocating engines and propellers. The crankshaft oscillatory velocities obtained from the simplified rigid body model are in good agreement with the experimental data for a SAITO-450 engine and a SOLO propeller at a 6″ pitch setting.

  19. A simplified approach to calculate atomic partition functions in plasmas

    SciTech Connect

    D'Ammando, Giuliano; Colonna, Gianpiero

    2013-03-15

    A simplified method to calculate the electronic partition functions and the corresponding thermodynamic properties of atomic species is presented and applied to C(I) up to C(VI) ions. The method consists in reducing the complex structure of an atom to three lumped levels. The ground level of the lumped model describes the ground term of the real atom, while the second lumped level represents the low lying states and the last one groups all the other atomic levels. It is also shown that for the purpose of thermodynamic function calculation, the energy and the statistical weight of the upper lumped level, describing high-lying excited atomic states, can be satisfactorily approximated by an analytic hydrogenlike formula. The results of the simplified method are in good agreement with those obtained by direct summation over a complete set (i.e., including all possible terms and configurations below a given cutoff energy) of atomic energy levels. The method can be generalized to include more lumped levels in order to improve the accuracy.

  20. Simplified design method for shear-valve magnetorheological dampers

    NASA Astrophysics Data System (ADS)

    Ding, Yang; Zhang, Lu; Zhu, Haitao; Li, Zhongxian

    2014-12-01

    Based on the Bingham parallel-plate model, a simplified design method of shear-valve magnetorheological (MR) dampers is proposed considering the magnetic circuit optimization. Correspondingly, a new MR damper with a full-length effective damping path is proposed. The prototype dampers are also fabricated and studied numerically and experimentally. According to the test results, the Bingham parallel-plate model is further modified to obtain a damping force prediction model of the proposed MR dampers. This prediction model considers the magnetic saturation phenomenon. The study indicates that the proposed simplified design method is simple, effective and reliable. The maximum damping force of the proposed MR dampers with a full-length effective damping path is at least twice as large as those of conventional MR dampers. The dynamic range of damping force increases by at least 70%. The proposed damping force prediction model considers the magnetic saturation phenomenon and it can realize the actual characteristic of MR fluids. The model is able to predict the actual damping force of MR dampers precisely.

  1. Development of Generation System of Simplified Digital Maps

    NASA Astrophysics Data System (ADS)

    Uchimura, Keiichi; Kawano, Masato; Tokitsu, Hiroki; Hu, Zhencheng

    In recent years, digital maps have been used in a variety of scenarios, including car navigation systems and map information services over the Internet. These digital maps are formed by multiple layers of maps of different scales; the map data most suitable for the specific situation are used. Currently, the production of map data of different scales is done by hand due to constraints related to processing time and accuracy. We conducted research concerning technologies for automatic generation of simplified map data from detailed map data. In the present paper, the authors propose the following: (1) a method to transform data related to streets, rivers, etc. containing widths into line data, (2) a method to eliminate the component points of the data, and (3) a method to eliminate data that lie below a certain threshold. In addition, in order to evaluate the proposed method, a user survey was conducted; in this survey we compared maps generated using the proposed method with the commercially available maps. From the viewpoint of the amount of data reduction and processing time, and on the basis of the results of the survey, we confirmed the effectiveness of the automatic generation of simplified maps using the proposed methods.

  2. Simplified Physics Based Models Research Topical Report on Task #2

    SciTech Connect

    Mishra, Srikanta; Ganesh, Priya

    2014-10-31

    We present a simplified-physics based approach, where only the most important physical processes are modeled, to develop and validate simplified predictive models of CO2 sequestration in deep saline formation. The system of interest is a single vertical well injecting supercritical CO2 into a 2-D layered reservoir-caprock system with variable layer permeabilities. We use a set of well-designed full-physics compositional simulations to understand key processes and parameters affecting pressure propagation and buoyant plume migration. Based on these simulations, we have developed correlations for dimensionless injectivity as a function of the slope of fractional-flow curve, variance of layer permeability values, and the nature of vertical permeability arrangement. The same variables, along with a modified gravity number, can be used to develop a correlation for the total storage efficiency within the CO2 plume footprint. Similar correlations are also developed to predict the average pressure within the injection reservoir, and the pressure buildup within the caprock.

  3. Simplified signal processing for impedance spectroscopy with spectrally sparse sequences

    NASA Astrophysics Data System (ADS)

    Annus, P.; Land, R.; Reidla, M.; Ojarand, J.; Mughal, Y.; Min, M.

    2013-04-01

    Classical method for measurement of the electrical bio-impedance involves excitation with sinusoidal waveform. Sinusoidal excitation at fixed frequency points enables wide variety of signal processing options, most general of them being Fourier transform. Multiplication with two quadrature waveforms at desired frequency could be easily accomplished both in analogue and in digital domains, even simplest quadrature square waves can be considered, which reduces signal processing task in analogue domain to synchronous switching followed by low pass filter, and in digital domain requires only additions. So called spectrally sparse excitation sequences (SSS), which have been recently introduced into bio-impedance measurement domain, are very reasonable choice when simultaneous multifrequency excitation is required. They have many good properties, such as ease of generation and good crest factor compared to similar multisinusoids. Typically, the usage of discrete or fast Fourier transform in signal processing step is considered so far. Usage of simplified methods nevertheless would reduce computational burden, and enable simpler, less costly and less energy hungry signal processing platforms. Accuracy of the measurement with SSS excitation when using different waveforms for quadrature demodulation will be compared in order to evaluate the feasibility of the simplified signal processing. Sigma delta modulated sinusoid (binary signal) is considered to be a good alternative for a synchronous demodulation.

  4. Simplified hydraulic model of French vertical-flow constructed wetlands.

    PubMed

    Arias, Luis; Bertrand-Krajewski, Jean-Luc; Molle, Pascal

    2014-01-01

    Designing vertical-flow constructed wetlands (VFCWs) to treat both rain events and dry weather flow is a complex task due to the stochastic nature of rain events. Dynamic models can help to improve design, but they usually prove difficult to handle for designers. This study focuses on the development of a simplified hydraulic model of French VFCWs using an empirical infiltration coefficient--infiltration capacity parameter (ICP). The model was fitted using 60-second-step data collected on two experimental French VFCW systems and compared with Hydrus 1D software. The model revealed a season-by-season evolution of the ICP that could be explained by the mechanical role of reeds. This simplified model makes it possible to define time-course shifts in ponding time and outlet flows. As ponding time hinders oxygen renewal, thus impacting nitrification and organic matter degradation, ponding time limits can be used to fix a reliable design when treating both dry and rain events. PMID:25225940

  5. An experimental approach to a simplified model of human birth.

    PubMed

    Lehn, Andrea M; Baumer, Alexa; Leftwich, Megan C

    2016-07-26

    This study presents a simplified experimental model of labor for the study of fetal lie and amniotic fluid properties. It mimics a ventouse (vacuum extraction) delivery to study the effect of amniotic fluid properties on force transfer to a passive fetus. The simplified vacuum delivery consists of a solid ovate spheroid being pulled from a passive, flexible spherical elastic shell filled with fluid. We compare the force necessary to remove the ovate fetus in fluids of varying properties. Additionally, the fetal lie-angular deviation from maternal/fetal spinal alignment-is changed by 5° intervals and the pullout force is measured. In both the concentric ovate experiments, the force to remove the fetus changes with the properties of the fluid occupying the space between the fetus and the uterus. Increasing the fluid viscosity by 35% decreases the maximum fetal removal force by up to 52.5%. Furthermore, while the force is dominated by the elastic force of the latex uterus, the properties of the amniotic fluid can significantly decrease the total removal force. This study demonstrates that the fluid components of a birth model can significantly alter the forces associated with fetus removal. This suggests that complete studies of human parturition should be designed to include both the material and fluid systems. PMID:26684434

  6. Encapsulated membrane proteins: A simplified system for molecular simulation.

    PubMed

    Lee, Sarah C; Khalid, Syma; Pollock, Naomi L; Knowles, Tim J; Edler, Karen; Rothnie, Alice J; R T Thomas, Owen; Dafforn, Timothy R

    2016-10-01

    Over the past 50years there has been considerable progress in our understanding of biomolecular interactions at an atomic level. This in turn has allowed molecular simulation methods employing full atomistic modelling at ever larger scales to develop. However, some challenging areas still remain where there is either a lack of atomic resolution structures or where the simulation system is inherently complex. An area where both challenges are present is that of membranes containing membrane proteins. In this review we analyse a new practical approach to membrane protein study that offers a potential new route to high resolution structures and the possibility to simplify simulations. These new approaches collectively recognise that preservation of the interaction between the membrane protein and the lipid bilayer is often essential to maintain structure and function. The new methods preserve these interactions by producing nano-scale disc shaped particles that include bilayer and the chosen protein. Currently two approaches lead in this area: the MSP system that relies on peptides to stabilise the discs, and SMALPs where an amphipathic styrene maleic acid copolymer is used. Both methods greatly enable protein production and hence have the potential to accelerate atomic resolution structure determination as well as providing a simplified format for simulations of membrane protein dynamics. This article is part of a Special Issue entitled: Biosimulations edited by Ilpo Vattulainen and Tomasz Róg. PMID:26946242

  7. Core Skills in Action.

    ERIC Educational Resources Information Center

    Further Education Unit, London (England).

    This bulletin provides an update on current developments in core skills in further education. Section 1 contains information about the Further Education Unit's (FEU's) Core Skills Post-16 project, in which colleges are testing principles that underpin all good quality learning programs. Important findings and examples are outlined under the five…

  8. Reconceptualising Core Skills

    ERIC Educational Resources Information Center

    Canning, Roy

    2007-01-01

    The paper provides an analysis of Core Skill policy and practice in the UK. The author presents a conceptual basis for re-thinking generic Core Skills within educational approaches in teaching and learning. The discussion looks at whether universal notions of generic skills are appropriate when considering post-compulsory pedagogic approaches to…

  9. The Common Core.

    ERIC Educational Resources Information Center

    Boyer, Ernest L.

    Current curricula in institutions of higher education are criticized in this speech for their lack of a common core of education. Several possibilities for developing such a common core include education centered around our common heritage and the challenges of the present. It is suggested that all students must be introduced to the events,…

  10. Making an Ice Core.

    ERIC Educational Resources Information Center

    Kopaska-Merkel, David C.

    1995-01-01

    Explains an activity in which students construct a simulated ice core. Materials required include only a freezer, food coloring, a bottle, and water. This hands-on exercise demonstrates how a glacier is formed, how ice cores are studied, and the nature of precision and accuracy in measurement. Suitable for grades three through eight. (Author/PVD)